Add saved payout destination UX and service contracts (#54)

docs/implementation.md

@@ -968,3 +968,31 @@ remain separate capabilities. Unrelated notifications runtime changes are exclud
 Delivered in [PR #51](https://git.sendico.io/tech/sxchnge/pulls/51), targeting
 `identity-verification-48`. Merge order is #47 → #49 → #51; deploy Sendico #2897
 before SXCHNGE #51. Both implementation branches are pushed and remain unmerged.
+
+## Saved payout destinations UX — #54
+
+Branch `payout-destinations-54`, based on `local-stand-52`. Implements Settings
+creation, details, rename, replacement and removal; explicit payout selection;
+optional saving and one-time preparation for crypto, cards and Russian personal
+accounts. Shared typed service/model/provider layers separate destination identity,
+metadata/execution revisions, ownership, provider bindings, contextual eligibility,
+save outcomes and financial outcomes. The customer-scoped demo replays stable
+created/duplicate results, preserves immutable quote/history snapshots, rechecks at
+acceptance, and demonstrates card-binding restoration without creating a second
+card. Bank directory/paste handling follows the reviewed Sendico interface.
+
+EN/RU and 320 px/1.6× layouts are tested. Formatting (44 changed Dart files),
+analysis of app/wallet/analytics, `make test-frontend` (including 89 app tests), and
+`flutter build web` with Wasm dry run passed. Browser smoke inspection confirmed
+bank form rendering, labeled controls and keyboard focus. Full assistive-technology
+and real-provider audits were not performed. No security scans were requested/run.
+
+Persistence and bindings in this delivery are simulated and reset on reload.
+Authenticated live mode retains explicit use of its provisioned payout destination;
+new types fail closed until the backend supplies the documented capabilities and
+registry/atomic-acceptance contracts. No routing, ownership-verification system,
+provider integration or financial engine was added. See
+[the specification and integration boundary](ux/payout-destinations.md).
+
+Stacked merge order: #47 → #49 → #51 → #53 → this contribution. The unrelated
+notifications runtime edit is preserved outside task commits. Delivery links follow.

docs/ux/payout-destinations.md

@@ -0,0 +1,252 @@
+# Saved payout destinations
+
+Task: tech/sxchnge#54. Branch: `payout-destinations-54`.
+
+## Delivery and integration boundary
+
+The Flutter app implements Settings management and payout selection/new/one-time
+flows with the injectable `DestinationService` in `sxchnge_wallet`. The included
+customer-scoped **demo** service is process-local: reload discards its saved
+records, attempts, directory fixtures and audit. No real card data may be entered.
+The existing live wallet remains connected to provisioned Sendico destinations,
+which now require explicit selection. Its existing financial adapter is unchanged.
+
+This is UX and supporting contract implementation, not a production destination
+registry or new payment-provider integration. Live mode never falls back to a
+simulated destination store. It exposes no new destination creation capabilities
+until the BFF implements the contract below. `BackendWalletService` explicitly
+rejects new typed inputs rather than dropping them or using a different destination.
+Actual persistent storage, public Sendico capability/directory adapters, secure
+card collection, binding recovery and atomic financial acceptance are integration
+requirements, not claims established by client tests. The injected service boundary
+lets a production implementation replace the demo without DTO/networking in widgets.
+
+## Screen annotations
+
+The four primary destinations remain Accounts, Activity, Limits and Settings.
+
+```text
+Settings → Payout methods
+  Add payout method                 [primary action]
+  Search saved methods              [nickname and safe display metadata]
+  Crypto addresses                  [type group; recently used first]
+    nickname / asset · network · shortened address
+    availability / required action [text, not color alone]
+  Bank cards
+    nickname / brand · masked suffix
+  Russian bank accounts
+    nickname / bank · masked suffix
+```
+
+```text
+Add payout method
+  Type                              [explicit selection]
+  Type-specific destination fields  [labels and inline validation]
+  Save for future payouts           [payout only; unchecked]
+  Name for this method (optional)   [Settings or saving enabled]
+  Validation / eligibility / saving [separate feedback]
+  Save payout method | Continue     [no ordinary confirmation dialog]
+```
+
+```text
+Pay out
+  Source account / available funds
+  Payout destination                [explicit selection every time]
+    Saved methods | New destination
+  Amount                            [preserved during navigation/recovery]
+  Review
+    full destination, source debit, fee, receiving amount/asset
+    network and memo/tag for crypto; card remains masked
+  Pay out [amount/currency]          [explicit consequential confirmation]
+  Processing → confirmed settlement [existing separate wallet states]
+```
+
+Settings: select type → details → Save. Payout: new destination → details → optional
+saving → Continue. Reuse: select saved method → amount → review → confirm. No
+mandatory nickname, routine ownership warning, automatic selection/substitution,
+or extra verification screen is added. Removal has a consequential confirmation.
+A replacement creates a new record; the original remains until explicitly removed.
+
+Lists group by destination type, sort recent use within groups and search safe
+labels. Empty category, search no-match, unavailable data and no eligible methods
+are distinct. Opening creation/management uses transient Navigator state, preserving
+payout input without destination details in URLs or serialized browser history.
+
+## Domain and service contract
+
+`DestinationInput` is `SavedReference(id, executionRevision)` or
+`OneTimeDestination(details)`. Validation and contextual eligibility apply equally
+to both; quoting/submitting a one-time input must not create a reusable record.
+
+A destination has a customer-owned opaque ID independent of provider bindings.
+Ownership declaration, service verification and payout eligibility are separate.
+Unverified details may be saved when saving policy permits. Ownership status is
+shown only when required/actionable. Format checks never establish ownership or
+receiving capability, and successful persistence never establishes payout eligibility.
+
+`metadataRevision` protects nickname updates; `executionRevision` protects identity,
+lifecycle and binding changes. Rename cannot invalidate a valid execution quote.
+Removal and binding changes require execution revalidation. Immutable identities
+are changed by replacement. Last-use ordering is not an execution change.
+
+Required service operations: capabilities; list/get; typed field validation;
+contextual assessment; create; creation-attempt lookup; duplicate resolution;
+rename with expected metadata revision; replacement; removal with expected
+revisions; bank lookup with cancellation; immutable quote preparation. Remediation
+capabilities must come from the service, never provider-specific widget logic.
+
+Eligibility uses current capabilities, available routes, destination requirements,
+ownership/security policy, bindings and payout context including amount when relevant.
+States are eligible, temporarily unavailable, requires action and unsupported.
+Settings retains active unavailable methods. A contextless Settings assessment is
+informational and never proof of eligibility for a particular payout. Selection,
+quote preparation and acceptance revalidate independently. Losing eligibility or
+removal preserves inputs and requires explicit reselection; never substitute.
+
+On Continue: validate fields; assess contextual eligibility; optionally persist
+under saving policy; proceed only if eligible. Persistence may succeed while the
+payout is ineligible. Definitive optional save failure allows retry or explicit
+one-time continuation. Unknown outcomes offer status lookup; eligible one-time
+continuation does not cancel/repeat a potentially successful save. Confirmation of
+saving, validation, submission and settlement are separate states.
+
+### Canonical identities and duplicate outcomes
+
+- Crypto: service-defined asset ID (including token-contract identity), canonical
+  network ID, network-normalized address and applicable memo/tag. Identical address
+  strings across networks/assets are distinct. Preserve presentation case and
+  meaningful memo contents. Display enough metadata to distinguish same-symbol tokens.
+- Russian bank: service-normalized BIK, account number and holder identity. No
+  frontend fuzzy matching or inference from an account prefix.
+- Card: reliable service/provider fingerprint where available, never brand/last-four,
+  expiry or capture token. Provider-scoped fingerprints are not globally portable.
+  Missing reliable fingerprint permits distinct records; never guess/merge.
+
+Creation keys identify immutable payloads. Replay returns the same **created** or
+**duplicate** result even after the referenced record is renamed/removed. Attempt
+lookup distinguishes these outcomes. Concurrent creation must serialize duplicate
+resolution within the authenticated customer scope. Use existing method revalidates
+that record and never creates another. Existing nicknames remain unchanged.
+
+The demo uses a synchronous customer-scoped mutation boundary; production needs
+persistent unique identity/idempotency constraints with transactions or equivalent.
+No duplicate endpoint may reveal another customer's destination or attempt.
+
+### Bank input adapted from Sendico
+
+Reviewed local Sendico checkout `c5a3440fa`, especially
+`docs/russian-bank-methods.md` and its form, lookup, parsing and validation tests.
+The form has Account holder, Bank details and optional nickname sections. Structured
+first/last names and optional patronymic preserve compound names; arbitrary full
+names are shown unsplit. Business/tax selectors are excluded from personal-account UX.
+Bank search is debounced 350 ms from two characters, with cancellation and stale
+response rejection. Results identify name, BIK and city. Selected bank is compact,
+with Change bank and expandable correspondent details. Account number accepts
+whitespace and preserves leading zeros; 20-digit/control-key checking is not ownership
+verification. Prefix hints remain advisory.
+
+Local paste import recognizes explicit EN/RU labels, previews recognized values,
+flags conflicts, preserves untouched fields and never persists/transmits raw pasted
+text. Directory/name/correspondent mismatches remain visible. Invalid BIK, unknown
+bank, unsupported institution and service failure are distinct. On reuse, cosmetic
+directory labels may refresh; execution-material changes require review/requote.
+Never silently replace BIK, account or holder. Mergers/BIK changes can require a
+replacement; discontinued banks remain saved but ineligible.
+
+### Cards and binding lifecycle
+
+Card saving requires reusable support or a defined restoration mechanism. An existing
+card remains saved after card/binding expiry, revocation or provider outage.
+Requires action means a supported recovery exists; operational outages are temporary;
+without a reusable binding or supported recovery the UI must not promise reuse.
+Bindings may be multiple, provider-scoped and nonportable. Re-tokenization requires
+trusted same-card identification; otherwise create a replacement. Secure capture is
+transient. Saved card details contain local identity/display metadata, and bindings
+contain separate opaque references; PAN/CVV never enter application storage.
+
+## Acceptance, security and retention
+
+The BFF's financial acceptance boundary must atomically validate current quote,
+customer authorization, execution revision, lifecycle, eligibility and requirements,
+then persist the accepted immutable snapshot/intent. A preceding API assessment or
+frontend check cannot guarantee financial correctness. Removal committed first rejects
+acceptance; acceptance committed first survives later removal. Rejection preserves
+drafts and returns reselect/review/refresh/requote actions. Expired or materially changed
+quotes need explicit confirmation of recalculated terms. This is a required backend
+contract; the demo's synchronous acceptance guard only demonstrates its semantics.
+
+Removal from the active list, binding deactivation and data erasure are separate.
+Removed records cannot serve new payouts; accepted payouts retain immutable snapshots.
+Production retention must assign explicit expiry/cleanup policies to abandoned quotes,
+capture references, idempotency records and required financial history. Do not promise
+complete erasure of retained financial records. The demo stores no browser data and
+expires transient quote leases; all remaining simulation data ends on reload.
+
+Authorize every operation server-side and audit actor, timestamp, opaque method/attempt,
+action and outcome, without destination details. Metadata edits use optimistic concurrency.
+Risk-based step-up is service-policy driven; no mandatory MFA is introduced. No raw
+destination, pasted text, nickname, amount or account data enters logs, analytics or replay.
+
+## Localization, accessibility and measurement
+
+EN/RU copy is maintained in the app ARB sources. Specific states cover saving,
+uncertainty, duplicate reuse, changed/removed methods, directory failures, binding
+authorization and quote recovery. Ordinary success says only "Payout method saved."
+Forms use associated labels, field errors, a focusable live feedback area, text status
+and keyboard controls. Names stack below 480 px in a 720 px maximum form. Review
+320 px layouts at 1.6× text scale, long labels, full-address wrapping and 48 px targets.
+
+`JourneyKind.destination` / `destinationSave` measures service-confirmed saving/resolution
+separately from the existing payout quote/submission/settlement signals. Retries share
+recorder correlation; confirmed save closes its journey. Idle/discard attempts use the
+shared 30-minute inactivity/disposal rule. Simulation events are explicitly marked.
+No production persistence, cross-session funnel or financial outcome is inferred from
+the demo recorder. Actual outcome events and backend audit are integration requirements.
+
+## Validation scenarios and recorded review
+
+Tests exercise one-time nonpersistence, idempotent/repeated/concurrent creation, stable
+duplicate replay after rename/removal, lost-response reconciliation, customer isolation,
+metadata concurrency, execution invalidation at acceptance, asset/network/token identity,
+case/memo handling, fingerprint fallback, card binding recovery states, bank control keys,
+directory changes, paste conflicts and DTO mappings. Widget tests exercise Settings
+save/rename/remove, explicit selection, one-time payout, optional-save failure recovery,
+removal during review, privacy-safe outcomes and EN/RU narrow layouts. Existing auth,
+factor, wallet and workspace regressions are included in the required frontend suite.
+
+Research: [Wise recipient management](https://wise.com/help/articles/2491526/how-do-i-add-or-delete-recipients),
+[Coinbase address books](https://help.coinbase.com/en/exchange/managing-my-account/how-does-the-address-book-work),
+[Coinbase memo/tag requirements](https://help.coinbase.com/en/coinbase/trading-and-funding/sending-or-receiving-cryptocurrency/destination-tag-memo-faq),
+[Stripe tokenization](https://docs.stripe.com/api/tokens),
+[W3C form validation](https://www.w3.org/WAI/tutorials/forms/validation/).
+
+Final validation commands and PR links are recorded below at delivery.
+
+### Completion review — 2026-10-16
+
+- Applied `review-frontend-change`, UX Design and UX Observability reviews across
+  app, wallet and analytics. Extracted form/search/selection/management providers;
+  widgets consume typed models and provider actions. Fixed narrow bank-header
+  overflow and bottom feedback overlapping management controls.
+- Added structured immutable destination review, explicit simulated receiving
+  asset/amount/timing terms, independent card-binding restoration and a typed
+  created/duplicate analytics outcome. Nickname edits do not change execution
+  revisions. New typed inputs are explicitly rejected by the legacy live adapter.
+- `dart format --output=none --set-exit-if-changed` over 44 changed Dart files:
+  passed, no changes. `git diff --check`: passed.
+- `flutter analyze` in `frontend/app`, `frontend/packages/sxchnge_wallet` and
+  `frontend/packages/sxchnge_analytics`: passed, no issues.
+- `make test-frontend`: passed all seven package/application suites, including
+  89 application tests and the destination domain/recovery/concurrency scenarios.
+- `flutter build web` in `frontend/app`: passed, including the Wasm dry run.
+- Browser smoke check on a temporary local web preview: method selection and bank
+  form rendered; accessibility labels exposed; Tab moved from type to First name.
+  Automated EN/RU forms at 320 px and 1.6× scale passed. A full assistive-technology
+  audit and production/provider validation were not performed.
+- An exploratory repository-root `flutter analyze` also inspected the unrelated
+  standalone `website/flutter/brand_palette.dart`, which lacks Flutter package
+  context and reported `dart:ui` errors. The required affected-package analyses
+  above passed; no unrelated website code or analyzer settings were changed.
+- No backend code or infrastructure changes, live payments, deployment, merge or
+  security scanner runs were performed. Live persistence/atomic acceptance remain
+  the explicitly documented integration boundary.

frontend/app/lib/destinations/bank.dart

@@ -0,0 +1,225 @@
+import 'package:flutter/material.dart';
+
+import 'package:provider/provider.dart';
+
+import 'package:sxchnge_wallet/sxchnge_wallet.dart';
+
+import 'paste.dart';
+
+import '../generated/i18n/app_localizations.dart';
+
+class BankFields extends StatefulWidget {
+  const BankFields({
+    super.key,
+    required this.onChanged,
+    this.initial,
+    this.errorField,
+  });
+  final ValueChanged<DestinationDetails?> onChanged;
+  final RussianBankDestination? initial;
+  final String? errorField;
+  @override
+  State<BankFields> createState() => _BankFieldsState();
+}
+
+class _BankFieldsState extends State<BankFields> {
+  late final first = TextEditingController(text: widget.initial?.firstName);
+  late final last = TextEditingController(text: widget.initial?.lastName);
+  late final patronymic = TextEditingController(
+    text: widget.initial?.patronymic,
+  );
+  late final account = TextEditingController(text: widget.initial?.account);
+  final query = TextEditingController();
+  late final search = BankSearchProvider(
+    context.read<DestinationsProvider>().service,
+  );
+  late Bank? bank = widget.initial?.bank;
+  String? pastedHolder;
+  bool conflict = false;
+  Map<String, String> pasted = {};
+  bool get mismatch =>
+      bank != null &&
+      ((pasted['bank'] != null && pasted['bank'] != bank!.name) ||
+          (pasted['correspondent'] != null &&
+              pasted['correspondent'] != bank!.correspondent));
+  void changed() => widget.onChanged(
+    bank == null
+        ? null
+        : RussianBankDestination(
+            firstName: first.text,
+            lastName: last.text,
+            patronymic: patronymic.text,
+            bank: bank!,
+            account: account.text,
+          ),
+  );
+  Future<void> paste() async {
+    final parsed = await showDialog<BankPaste>(
+      context: context,
+      builder: (_) => const BankPasteDialog(),
+    );
+    if (!mounted || parsed == null) return;
+    for (final entry in {
+      'firstName': first,
+      'lastName': last,
+      'patronymic': patronymic,
+      'account': account,
+    }.entries) {
+      if (parsed.conflicts.contains(entry.key)) {
+        entry.value.clear();
+      } else if (parsed.values[entry.key] case final String value) {
+        entry.value.text = value;
+      }
+    }
+    setState(() {
+      pasted = parsed.values;
+      conflict = parsed.conflicts.isNotEmpty;
+      pastedHolder = parsed.values['holder'];
+    });
+    if (parsed.conflicts.contains('bik')) {
+      setState(() => bank = null);
+    }
+    if (parsed.values['bik'] case final String bik) {
+      query.text = bik;
+      search.search(bik);
+      setState(() => bank = null);
+    }
+    changed();
+  }
+
+  @override
+  void dispose() {
+    for (final c in [first, last, patronymic, account, query]) {
+      c.dispose();
+    }
+    search.dispose();
+    super.dispose();
+  }
+
+  Widget field(
+    String label,
+    TextEditingController c, {
+    String? id,
+    bool numeric = false,
+    String? error,
+  }) => Padding(
+    padding: const EdgeInsets.only(bottom: 16),
+    child: TextField(
+      key: id == null ? null : ValueKey(id),
+      controller: c,
+      keyboardType: numeric ? TextInputType.number : TextInputType.name,
+      decoration: InputDecoration(labelText: label, errorText: error),
+      onChanged: (_) => changed(),
+    ),
+  );
+  @override
+  Widget build(BuildContext context) {
+    final l = AppLocalizations.of(context)!;
+    return Column(
+      crossAxisAlignment: CrossAxisAlignment.stretch,
+      children: [
+        Text(l.dHolder, style: Theme.of(context).textTheme.titleMedium),
+        const SizedBox(height: 16),
+        LayoutBuilder(
+          builder: (context, b) {
+            final a = field(
+              l.dFirst,
+              first,
+              id: 'destination-first',
+              error: widget.errorField == 'holder' ? l.dInvalid : null,
+            );
+            final z = field(l.dLast, last, id: 'destination-last');
+            return b.maxWidth >= 480
+                ? Row(
+                    crossAxisAlignment: CrossAxisAlignment.start,
+                    children: [
+                      Expanded(child: a),
+                      const SizedBox(width: 12),
+                      Expanded(child: z),
+                    ],
+                  )
+                : Column(children: [a, z]);
+          },
+        ),
+        field(l.dPatronymic, patronymic),
+        if (pastedHolder != null) SelectableText(pastedHolder!),
+        if (conflict) Text(l.dPasteConflict),
+        Text(l.dBankDetails, style: Theme.of(context).textTheme.titleMedium),
+        Align(
+          alignment: Alignment.centerLeft,
+          child: TextButton.icon(
+            onPressed: paste,
+            icon: const Icon(Icons.content_paste),
+            label: Text(l.dPaste),
+          ),
+        ),
+        ListenableBuilder(
+          listenable: search,
+          builder: (context, _) => Column(
+            crossAxisAlignment: CrossAxisAlignment.stretch,
+            children: [
+              if (bank == null) ...[
+                TextField(
+                  controller: query,
+                  decoration: InputDecoration(labelText: l.dBankSearch),
+                  onChanged: search.search,
+                ),
+                if (search.loading) const LinearProgressIndicator(),
+                for (final b in search.results)
+                  ListTile(
+                    title: Text(b.name),
+                    subtitle: Text('${b.bik} · ${b.city}'),
+                    onTap: () {
+                      setState(() => bank = b);
+                      changed();
+                    },
+                  ),
+                if (search.error != null)
+                  Text(
+                    search.error == DestinationIssue.unavailable
+                        ? l.dBankFailure
+                        : l.dBankUnknown,
+                  ),
+                if (search.error == DestinationIssue.unavailable)
+                  TextButton(
+                    onPressed: () => search.search(query.text),
+                    child: Text(l.wRefresh),
+                  ),
+              ] else ...[
+                ListTile(
+                  contentPadding: EdgeInsets.zero,
+                  title: Text(bank!.name),
+                  subtitle: Text('${l.dBik} ${bank!.bik}'),
+                  trailing: TextButton(
+                    onPressed: () {
+                      setState(() => bank = null);
+                      changed();
+                    },
+                    child: Text(l.dChangeBank),
+                  ),
+                ),
+                ExpansionTile(
+                  title: Text(l.dBankDetails),
+                  children: [
+                    SelectableText(
+                      '${l.dCorrespondent}: ${bank!.correspondent}',
+                    ),
+                  ],
+                ),
+                if (!bank!.supported) Text(l.dUnsupported),
+              ],
+            ],
+          ),
+        ),
+        const SizedBox(height: 16),
+        field(
+          l.dAccount,
+          account,
+          id: 'destination-account',
+          numeric: true,
+          error: widget.errorField == 'account' ? l.dInvalid : null,
+        ),
+      ],
+    );
+  }
+}

frontend/app/lib/destinations/copy.dart

@@ -0,0 +1,33 @@
+import 'package:sxchnge_wallet/sxchnge_wallet.dart';
+
+import '../generated/i18n/app_localizations.dart';
+
+String destinationType(AppLocalizations l, DestinationType type) =>
+    switch (type) {
+      DestinationType.crypto => l.dCrypto,
+      DestinationType.card => l.dCard,
+      DestinationType.russianBank => l.dBank,
+    };
+String destinationIssue(AppLocalizations l, DestinationIssue issue) =>
+    switch (issue) {
+      DestinationIssue.invalid => l.dInvalid,
+      DestinationIssue.unavailable => l.dTemporary,
+      DestinationIssue.uncertain => l.dUncertain,
+      DestinationIssue.conflict => l.dConflict,
+      DestinationIssue.removed => l.dRemoved,
+      DestinationIssue.expired => l.dCardExpired,
+      DestinationIssue.bankChanged => l.dBankChanged,
+      DestinationIssue.authorization => l.dAuthorization,
+      DestinationIssue.unsupported => l.dUnsupported,
+      DestinationIssue.duplicate => l.dDuplicate,
+      DestinationIssue.replacementRequired => l.dReplacementRequired,
+    };
+String eligibilityText(AppLocalizations l, PayoutEligibility e) =>
+    e.reason != null
+    ? destinationIssue(l, e.reason!)
+    : switch (e.state) {
+        EligibilityState.eligible => l.dEligible,
+        EligibilityState.temporarilyUnavailable => l.dTemporary,
+        EligibilityState.requiresAction => l.dAction,
+        EligibilityState.unsupported => l.dUnsupported,
+      };

frontend/app/lib/destinations/crypto.dart

@@ -0,0 +1,128 @@
+import 'package:flutter/material.dart';
+
+import 'package:sxchnge_wallet/sxchnge_wallet.dart';
+
+import '../generated/i18n/app_localizations.dart';
+
+class CryptoFields extends StatefulWidget {
+  const CryptoFields({
+    super.key,
+    required this.capabilities,
+    required this.onChanged,
+    this.initial,
+    this.errorField,
+  });
+  final DestinationCapabilities capabilities;
+  final ValueChanged<DestinationDetails?> onChanged;
+  final CryptoDestination? initial;
+  final String? errorField;
+  @override
+  State<CryptoFields> createState() => _CryptoFieldsState();
+}
+
+class _CryptoFieldsState extends State<CryptoFields> {
+  late final address = TextEditingController(text: widget.initial?.address);
+  late final memo = TextEditingController(text: widget.initial?.memo);
+  late String? assetId = widget.initial?.assetId;
+  late String? networkId = widget.initial?.networkId;
+  void changed() {
+    final a = widget.capabilities.assets
+        .where((a) => a.id == assetId && a.networkId == networkId)
+        .firstOrNull;
+    widget.onChanged(
+      a == null
+          ? null
+          : CryptoDestination(
+              assetId: a.id,
+              networkId: a.networkId,
+              address: address.text,
+              memo: memo.text,
+              assetLabel: a.label,
+              networkLabel: a.networkLabel,
+            ),
+    );
+  }
+
+  @override
+  void dispose() {
+    address.dispose();
+    memo.dispose();
+    super.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final l = AppLocalizations.of(context)!;
+    final assets = widget.capabilities.assets;
+    final selected = assets
+        .where((a) => a.id == assetId && a.networkId == networkId)
+        .firstOrNull;
+    return Column(
+      crossAxisAlignment: CrossAxisAlignment.stretch,
+      children: [
+        DropdownButtonFormField<String>(
+          key: ValueKey('asset-$assetId'),
+          initialValue: assets.any((a) => a.id == assetId) ? assetId : null,
+          isExpanded: true,
+          decoration: InputDecoration(labelText: l.dAsset),
+          items: [
+            for (final a in assets)
+              DropdownMenuItem(value: a.id, child: Text(a.label)),
+          ],
+          onChanged: (v) {
+            setState(() {
+              assetId = v;
+              networkId = null;
+              memo.clear();
+            });
+            changed();
+          },
+        ),
+        const SizedBox(height: 16),
+        DropdownButtonFormField<String>(
+          key: ValueKey('network-$assetId-$networkId'),
+          initialValue:
+              assets.any((a) => a.id == assetId && a.networkId == networkId)
+              ? networkId
+              : null,
+          isExpanded: true,
+          decoration: InputDecoration(labelText: l.dNetwork),
+          items: [
+            for (final a in assets.where((a) => a.id == assetId))
+              DropdownMenuItem(value: a.networkId, child: Text(a.networkLabel)),
+          ],
+          onChanged: (v) {
+            setState(() => networkId = v);
+            changed();
+          },
+        ),
+        const SizedBox(height: 16),
+        TextField(
+          key: const ValueKey('destination-address'),
+          controller: address,
+          autocorrect: false,
+          enableSuggestions: false,
+          decoration: InputDecoration(
+            labelText: l.dAddress,
+            errorText: widget.errorField == 'address' ? l.dInvalid : null,
+          ),
+          onChanged: (_) => changed(),
+        ),
+        if (selected?.memoSupported == true) ...[
+          const SizedBox(height: 16),
+          TextField(
+            key: const ValueKey('destination-memo'),
+            controller: memo,
+            decoration: InputDecoration(
+              labelText: l.dMemo,
+              errorText: widget.errorField == 'memo' ? l.dInvalid : null,
+            ),
+            onChanged: (_) => changed(),
+          ),
+        ],
+        const SizedBox(height: 12),
+        Text(l.dCryptoHelp),
+      ],
+    );
+  }
+}

frontend/app/lib/destinations/detail.dart

@@ -0,0 +1,161 @@
+import 'package:flutter/material.dart';
+
+import 'package:provider/provider.dart';
+
+import 'package:sxchnge_wallet/sxchnge_wallet.dart';
+
+import 'copy.dart';
+import 'details.dart';
+import 'form.dart';
+import 'nickname.dart';
+
+import '../generated/i18n/app_localizations.dart';
+
+class DestinationDetailPage extends StatefulWidget {
+  const DestinationDetailPage({super.key, required this.destination});
+  final SavedDestination destination;
+  @override
+  State<DestinationDetailPage> createState() => _DestinationDetailPageState();
+}
+
+class _DestinationDetailPageState extends State<DestinationDetailPage> {
+  late final p = DestinationManagementProvider(
+    context.read<DestinationsProvider>().service,
+    widget.destination,
+  );
+  late final nickname = TextEditingController(
+    text: widget.destination.nickname,
+  );
+  Future<void> remove() async {
+    final l = AppLocalizations.of(context)!;
+    final confirmed = await showDialog<bool>(
+      context: context,
+      builder: (context) => AlertDialog(
+        title: Text(l.dRemoveTitle),
+        content: Text(l.dRemoveHelp),
+        actions: [
+          TextButton(
+            onPressed: () => Navigator.pop(context, false),
+            child: Text(l.wStay),
+          ),
+          FilledButton(
+            onPressed: () => Navigator.pop(context, true),
+            child: Text(l.dRemove),
+          ),
+        ],
+      ),
+    );
+    if (!mounted || confirmed != true) return;
+    await p.remove();
+    if (mounted && p.removed) Navigator.pop(context);
+  }
+
+  @override
+  void dispose() {
+    p.dispose();
+    nickname.dispose();
+    super.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final l = AppLocalizations.of(context)!;
+    return ListenableBuilder(
+      listenable: p,
+      builder: (context, _) => Scaffold(
+        appBar: AppBar(title: Text(l.dDetails)),
+        body: SingleChildScrollView(
+          padding: const EdgeInsets.fromLTRB(24, 24, 24, 120),
+          child: Center(
+            child: ConstrainedBox(
+              constraints: const BoxConstraints(maxWidth: 720),
+              child: Column(
+                crossAxisAlignment: CrossAxisAlignment.stretch,
+                children: [
+                  DestinationDetailsView(details: p.destination.details),
+                  const SizedBox(height: 24),
+                  DestinationNickname(
+                    controller: nickname,
+                    enabled: !p.busy,
+                    onChanged: (_) {},
+                  ),
+                  if (p.busy) const LinearProgressIndicator(),
+                  if (p.error != null) ...[
+                    Semantics(
+                      liveRegion: true,
+                      child: Text(destinationIssue(l, p.error!)),
+                    ),
+                    TextButton(
+                      onPressed: p.busy ? null : p.refresh,
+                      child: Text(l.dReload),
+                    ),
+                  ],
+                  const SizedBox(height: 16),
+                  FilledButton(
+                    onPressed: p.busy
+                        ? null
+                        : () async {
+                            await p.rename(nickname.text);
+                            if (context.mounted && p.error == null) {
+                              ScaffoldMessenger.of(
+                                context,
+                              ).showSnackBar(SnackBar(content: Text(l.dSaved)));
+                            }
+                          },
+                    child: Text(l.dRename),
+                  ),
+                  if (p.destination.details is CardDestination &&
+                      context
+                              .read<DestinationsProvider>()
+                              .capabilities
+                              ?.cardRecovery ==
+                          true)
+                    OutlinedButton(
+                      onPressed: p.busy
+                          ? null
+                          : () async {
+                              final restored =
+                                  await Navigator.push<DestinationInput>(
+                                    context,
+                                    MaterialPageRoute(
+                                      builder: (_) => DestinationFormPage(
+                                        initial: p.destination.details,
+                                        restoring: p.destination.input,
+                                      ),
+                                    ),
+                                  );
+                              if (mounted && restored != null) {
+                                await p.refresh();
+                              }
+                            },
+                      child: Text(l.dUpdateAuthorization),
+                    ),
+                  TextButton(
+                    onPressed: p.busy
+                        ? null
+                        : () async {
+                            await Navigator.push<DestinationInput>(
+                              context,
+                              MaterialPageRoute(
+                                builder: (_) => DestinationFormPage(
+                                  initial: p.destination.details,
+                                  replacing: p.destination.id,
+                                ),
+                              ),
+                            );
+                          },
+                    child: Text(l.dReplace),
+                  ),
+                  TextButton(
+                    onPressed: p.busy ? null : remove,
+                    child: Text(l.dRemove),
+                  ),
+                ],
+              ),
+            ),
+          ),
+        ),
+      ),
+    );
+  }
+}

frontend/app/lib/destinations/details.dart

@@ -0,0 +1,41 @@
+import 'package:flutter/material.dart';
+
+import 'package:sxchnge_wallet/sxchnge_wallet.dart';
+
+import '../generated/i18n/app_localizations.dart';
+
+/// Structured review renders the immutable service snapshot, never a nickname.
+class DestinationDetailsView extends StatelessWidget {
+  const DestinationDetailsView({super.key, required this.details});
+  final DestinationDetails details;
+  Widget field(String label, String value) => Padding(
+    padding: const EdgeInsets.only(top: 12),
+    child: Column(
+      crossAxisAlignment: CrossAxisAlignment.stretch,
+      children: [Text(label), SelectableText(value)],
+    ),
+  );
+  @override
+  Widget build(BuildContext context) {
+    final l = AppLocalizations.of(context)!;
+    return Column(
+      crossAxisAlignment: CrossAxisAlignment.stretch,
+      children: switch (details) {
+        CryptoDestination d => [
+          field(l.dAsset, d.assetLabel),
+          field(l.dNetwork, d.networkLabel),
+          field(l.dAddress, d.address),
+          field(l.dMemo, d.memo.isEmpty ? l.dNoMemo : d.memo),
+        ],
+        CardDestination d => [field(l.dCard, d.display)],
+        RussianBankDestination d => [
+          field(l.dHolder, d.holder),
+          field(l.dBankSearch, d.bank.name),
+          field(l.dBik, d.bank.bik),
+          field(l.dAccount, d.account),
+          field(l.dCorrespondent, d.bank.correspondent),
+        ],
+      },
+    );
+  }
+}

frontend/app/lib/destinations/form.dart

@@ -0,0 +1,292 @@
+import 'package:flutter/material.dart';
+
+import 'package:provider/provider.dart';
+
+import 'package:sxchnge_analytics/sxchnge_analytics.dart';
+
+import 'package:sxchnge_wallet/sxchnge_wallet.dart';
+
+import 'bank.dart';
+import 'copy.dart';
+import 'crypto.dart';
+import 'nickname.dart';
+
+import '../generated/i18n/app_localizations.dart';
+
+class DestinationFormPage extends StatefulWidget {
+  const DestinationFormPage({
+    super.key,
+    this.payoutContext,
+    this.initial,
+    this.replacing,
+    this.restoring,
+  });
+  final PayoutContext? payoutContext;
+  final DestinationDetails? initial;
+  final String? replacing;
+  final SavedReference? restoring;
+  @override
+  State<DestinationFormPage> createState() => _DestinationFormPageState();
+}
+
+class _DestinationFormPageState extends State<DestinationFormPage> {
+  late final p = DestinationFormProvider(
+    context.read<DestinationsProvider>().service,
+    context.read<AnalyticsService>(),
+    context: widget.payoutContext,
+    initial: widget.initial,
+    replacing: widget.replacing,
+    restoring: widget.restoring,
+  );
+  late DestinationType? type = widget.initial?.type;
+  final nickname = TextEditingController();
+  final focus = FocusNode();
+  Future<void> proceed({
+    bool withoutSaving = false,
+    bool existing = false,
+  }) async {
+    if (existing) {
+      await p.useExisting();
+    } else {
+      await p.proceed(withoutSaving: withoutSaving);
+    }
+    if (!mounted) return;
+    if (p.result != null) {
+      final l = AppLocalizations.of(context)!;
+      if (p.saved?.outcome == SaveOutcome.created || widget.restoring != null) {
+        ScaffoldMessenger.of(context).showSnackBar(
+          SnackBar(
+            content: Text(
+              widget.restoring == null ? l.dSaved : l.dAuthorizationUpdated,
+            ),
+          ),
+        );
+      }
+      Navigator.pop(context, p.result);
+      return;
+    }
+    focus.requestFocus();
+  }
+
+  @override
+  void dispose() {
+    p.dispose();
+    nickname.dispose();
+    focus.dispose();
+    super.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final l = AppLocalizations.of(context)!;
+    final caps = context.watch<DestinationsProvider>().capabilities;
+    return ListenableBuilder(
+      listenable: p,
+      builder: (context, _) => PopScope(
+        canPop: !p.busy,
+        child: Scaffold(
+          appBar: AppBar(title: Text(l.dAdd)),
+          body: SingleChildScrollView(
+            padding: const EdgeInsets.all(24),
+            child: Center(
+              child: ConstrainedBox(
+                constraints: const BoxConstraints(maxWidth: 720),
+                child: Column(
+                  crossAxisAlignment: CrossAxisAlignment.stretch,
+                  children: [
+                    if (caps?.simulated == true) ...[
+                      Text(l.dDemo),
+                      const SizedBox(height: 16),
+                    ],
+                    Text(l.dOwn),
+                    const SizedBox(height: 20),
+                    if (caps == null || caps.types.isEmpty)
+                      Text(l.dNoCapabilities)
+                    else ...[
+                      DropdownButtonFormField<DestinationType>(
+                        initialValue: caps.types.contains(type) ? type : null,
+                        isExpanded: true,
+                        decoration: InputDecoration(labelText: l.dType),
+                        items: [
+                          for (final t in caps.types)
+                            DropdownMenuItem(
+                              value: t,
+                              child: Text(
+                                destinationType(l, t),
+                                maxLines: 1,
+                                overflow: TextOverflow.ellipsis,
+                              ),
+                            ),
+                        ],
+                        onChanged:
+                            p.busy || p.uncertain || widget.restoring != null
+                            ? null
+                            : (v) {
+                                setState(() => type = v);
+                                p.change(null);
+                              },
+                      ),
+                      const SizedBox(height: 20),
+                      AbsorbPointer(
+                        absorbing: p.busy || p.uncertain,
+                        child: Column(
+                          crossAxisAlignment: CrossAxisAlignment.stretch,
+                          children: [
+                            if (type == DestinationType.crypto)
+                              CryptoFields(
+                                capabilities: caps,
+                                initial: widget.initial is CryptoDestination
+                                    ? widget.initial as CryptoDestination
+                                    : null,
+                                errorField: p.errorField,
+                                onChanged: p.change,
+                              ),
+                            if (type == DestinationType.russianBank)
+                              BankFields(
+                                initial:
+                                    widget.initial is RussianBankDestination
+                                    ? widget.initial as RussianBankDestination
+                                    : null,
+                                errorField: p.errorField,
+                                onChanged: p.change,
+                              ),
+                            if (type == DestinationType.card &&
+                                caps.simulated) ...[
+                              Text(l.dCardDemo),
+                              const SizedBox(height: 16),
+                              RadioGroup<String>(
+                                groupValue: p.details is CardDestination
+                                    ? (p.details as CardDestination).capture
+                                    : null,
+                                onChanged: (value) {
+                                  if (value != null) {
+                                    p.change(
+                                      CardDestination(
+                                        capture: value,
+                                        brand: 'Demo card',
+                                        last4: '4242',
+                                        expiryMonth: 12,
+                                        expiryYear: 2030,
+                                      ),
+                                    );
+                                  }
+                                },
+                                child: Column(
+                                  children: [
+                                    RadioListTile<String>(
+                                      value: 'demo-card-ready',
+                                      title: Text(l.dCardReady),
+                                    ),
+                                    RadioListTile<String>(
+                                      value: 'demo-card-recover',
+                                      title: Text(l.dCardRecover),
+                                    ),
+                                  ],
+                                ),
+                              ),
+                            ],
+                            if (type == DestinationType.card && !caps.simulated)
+                              Text(l.dNoCapabilities),
+                            if (widget.payoutContext != null) ...[
+                              const SizedBox(height: 16),
+                              CheckboxListTile(
+                                contentPadding: EdgeInsets.zero,
+                                value: p.save,
+                                onChanged: (v) => p.preferences(save: v),
+                                title: Text(l.dSaveFuture),
+                              ),
+                            ],
+                            if (widget.restoring == null &&
+                                (widget.payoutContext == null || p.save)) ...[
+                              const SizedBox(height: 16),
+                              DestinationNickname(
+                                controller: nickname,
+                                enabled: !p.busy && !p.uncertain,
+                                onChanged: (v) => p.preferences(nickname: v),
+                              ),
+                            ],
+                          ],
+                        ),
+                      ),
+                      const SizedBox(height: 16),
+                      Focus(
+                        focusNode: focus,
+                        skipTraversal: true,
+                        child: Semantics(
+                          liveRegion: true,
+                          child: Column(
+                            crossAxisAlignment: CrossAxisAlignment.stretch,
+                            children: [
+                              if (p.error != null)
+                                Text(
+                                  p.uncertain
+                                      ? l.dUncertain
+                                      : p.errorField != null
+                                      ? l.dInvalid
+                                      : '${p.savingFailed ? '${l.dSaveFailed}\n' : ''}${destinationIssue(l, p.error!)}',
+                                  key: const ValueKey('destination-error'),
+                                ),
+                              if (p.eligibility != null &&
+                                  !p.eligibility!.eligible)
+                                Text(
+                                  '${p.saved != null ? '${l.dSavedIneligible}\n' : ''}${eligibilityText(l, p.eligibility!)}',
+                                ),
+                              if (p.saved?.outcome ==
+                                  SaveOutcome.duplicate) ...[
+                                Text(l.dDuplicate),
+                                TextButton(
+                                  onPressed: p.busy
+                                      ? null
+                                      : () => proceed(existing: true),
+                                  child: Text(l.dUseExisting),
+                                ),
+                              ],
+                              if (p.saved?.outcome == SaveOutcome.created &&
+                                  p.result == null)
+                                Text(l.dSaved),
+                            ],
+                          ),
+                        ),
+                      ),
+                      if (p.busy) const LinearProgressIndicator(),
+                      if (p.uncertain)
+                        TextButton(
+                          onPressed: p.busy ? null : () => proceed(),
+                          child: Text(l.dCheckSave),
+                        ),
+                      if (p.savingFailed && widget.payoutContext != null)
+                        TextButton(
+                          onPressed: p.busy
+                              ? null
+                              : () => proceed(withoutSaving: true),
+                          child: Text(l.dWithoutSave),
+                        ),
+                      if (p.save && widget.payoutContext != null)
+                        Text(l.dSaveHelp),
+                      const SizedBox(height: 12),
+                      FilledButton(
+                        key: const ValueKey('destination-continue'),
+                        onPressed: p.busy || p.details == null
+                            ? null
+                            : () => proceed(),
+                        child: Text(
+                          widget.restoring != null
+                              ? l.dUpdateAuthorization
+                              : widget.payoutContext == null
+                              ? l.dSave
+                              : p.error != null && !p.uncertain
+                              ? l.dRetrySave
+                              : l.dContinue,
+                        ),
+                      ),
+                    ],
+                  ],
+                ),
+              ),
+            ),
+          ),
+        ),
+      ),
+    );
+  }
+}

frontend/app/lib/destinations/list.dart

@@ -0,0 +1,165 @@
+import 'package:flutter/material.dart';
+
+import 'package:provider/provider.dart';
+
+import 'package:sxchnge_wallet/sxchnge_wallet.dart';
+
+import 'copy.dart';
+import 'detail.dart';
+import 'form.dart';
+
+import '../generated/i18n/app_localizations.dart';
+
+class DestinationsPage extends StatefulWidget {
+  const DestinationsPage({super.key, this.payoutContext});
+  final PayoutContext? payoutContext;
+  @override
+  State<DestinationsPage> createState() => _DestinationsPageState();
+}
+
+class _DestinationsPageState extends State<DestinationsPage> {
+  String query = '';
+  late final selection = DestinationSelectionProvider(
+    context.read<DestinationsProvider>().service,
+    widget.payoutContext ?? const PayoutContext(''),
+  );
+  Future<void> refresh() async {
+    final p = context.read<DestinationsProvider>();
+    await p.refresh();
+    if (!mounted) return;
+    await selection.assess(p.methods);
+  }
+
+  @override
+  void initState() {
+    super.initState();
+    WidgetsBinding.instance.addPostFrameCallback((_) {
+      if (mounted) refresh();
+    });
+  }
+
+  Future<void> add() async {
+    final result = await Navigator.push<DestinationInput>(
+      context,
+      MaterialPageRoute(
+        builder: (_) =>
+            DestinationFormPage(payoutContext: widget.payoutContext),
+      ),
+    );
+    if (!mounted) return;
+    if (result != null && widget.payoutContext != null) {
+      Navigator.pop(context, result);
+    } else {
+      await refresh();
+    }
+  }
+
+  Future<void> choose(SavedDestination d) async {
+    if (widget.payoutContext == null) {
+      await Navigator.push<void>(
+        context,
+        MaterialPageRoute(
+          builder: (_) => DestinationDetailPage(destination: d),
+        ),
+      );
+      if (mounted) await refresh();
+    } else {
+      final ref = await selection.select(d);
+      if (mounted && ref != null) Navigator.pop(context, ref);
+    }
+  }
+
+  @override
+  void dispose() {
+    selection.dispose();
+    super.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final l = AppLocalizations.of(context)!;
+    final p = context.watch<DestinationsProvider>();
+    return Scaffold(
+      appBar: AppBar(
+        title: Text(widget.payoutContext == null ? l.dTitle : l.dChoose),
+        actions: [
+          IconButton(
+            tooltip: l.dReload,
+            onPressed: p.loading ? null : refresh,
+            icon: const Icon(Icons.refresh),
+          ),
+        ],
+      ),
+      body: ListenableBuilder(
+        listenable: selection,
+        builder: (context, _) => ListView(
+          padding: const EdgeInsets.all(24),
+          children: [
+            if (p.capabilities?.simulated == true) ...[
+              Text(l.dDemo),
+              const SizedBox(height: 16),
+            ],
+            FilledButton.icon(
+              onPressed: p.loading || (p.capabilities?.types.isEmpty ?? true)
+                  ? null
+                  : add,
+              icon: const Icon(Icons.add),
+              label: Text(widget.payoutContext == null ? l.dAdd : l.dNew),
+            ),
+            if (p.capabilities?.types.isEmpty == true)
+              Text(l.dManagementUnavailable),
+            const SizedBox(height: 20),
+            TextField(
+              decoration: InputDecoration(
+                labelText: l.dSearch,
+                prefixIcon: const Icon(Icons.search),
+              ),
+              onChanged: (v) => setState(() => query = v),
+            ),
+            if (p.loading || selection.busy) const LinearProgressIndicator(),
+            if (p.failed) Text(l.dUnavailable),
+            if (selection.error != null)
+              Semantics(
+                liveRegion: true,
+                child: Text(destinationIssue(l, selection.error!)),
+              ),
+            if (widget.payoutContext != null &&
+                !p.loading &&
+                p.methods.isNotEmpty &&
+                !selection.assessments.values.any((a) => a.eligible))
+              Text(l.dNoEligible),
+            for (final type
+                in p.capabilities?.types ?? <DestinationType>[]) ...[
+              const SizedBox(height: 24),
+              Text(
+                destinationType(l, type),
+                style: Theme.of(context).textTheme.titleLarge,
+              ),
+              const SizedBox(height: 8),
+              if (p.search(query, type).isEmpty && !p.loading && !p.failed)
+                Text(query.isEmpty ? l.dEmpty : l.dNoMatches),
+              for (final d in p.search(query, type))
+                Card(
+                  child: ListTile(
+                    contentPadding: const EdgeInsets.all(16),
+                    title: Text(d.label),
+                    subtitle: Column(
+                      crossAxisAlignment: CrossAxisAlignment.start,
+                      children: [
+                        if (d.nickname.isNotEmpty) Text(d.details.display),
+                        if (selection.assessments[d.id]
+                            case final PayoutEligibility e)
+                          Text(eligibilityText(l, e)),
+                      ],
+                    ),
+                    trailing: const Icon(Icons.chevron_right),
+                    onTap: selection.busy ? null : () => choose(d),
+                  ),
+                ),
+            ],
+          ],
+        ),
+      ),
+    );
+  }
+}

frontend/app/lib/destinations/nickname.dart

@@ -0,0 +1,26 @@
+import 'package:flutter/material.dart';
+
+import '../generated/i18n/app_localizations.dart';
+
+class DestinationNickname extends StatelessWidget {
+  const DestinationNickname({
+    super.key,
+    required this.controller,
+    required this.onChanged,
+    this.enabled = true,
+  });
+  final TextEditingController controller;
+  final ValueChanged<String> onChanged;
+  final bool enabled;
+  @override
+  Widget build(BuildContext context) => TextField(
+    key: const ValueKey('destination-nickname'),
+    controller: controller,
+    enabled: enabled,
+    maxLength: 80,
+    decoration: InputDecoration(
+      labelText: AppLocalizations.of(context)!.dNickname,
+    ),
+    onChanged: onChanged,
+  );
+}

frontend/app/lib/destinations/paste.dart

@@ -0,0 +1,79 @@
+import 'package:flutter/material.dart';
+
+import 'package:sxchnge_wallet/sxchnge_wallet.dart';
+
+import '../generated/i18n/app_localizations.dart';
+
+class BankPasteDialog extends StatefulWidget {
+  const BankPasteDialog({super.key});
+  @override
+  State<BankPasteDialog> createState() => _BankPasteDialogState();
+}
+
+class _BankPasteDialogState extends State<BankPasteDialog> {
+  final text = TextEditingController();
+  BankPaste? result;
+  @override
+  void dispose() {
+    text.clear();
+    text.dispose();
+    super.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final l = AppLocalizations.of(context)!;
+    final labels = {
+      'firstName': l.dFirst,
+      'lastName': l.dLast,
+      'patronymic': l.dPatronymic,
+      'account': l.dAccount,
+      'bik': 'BIK',
+      'bank': l.dBankSearch,
+      'holder': l.dHolder,
+      'correspondent': l.dCorrespondent,
+    };
+    return AlertDialog(
+      title: Text(l.dPaste),
+      content: SizedBox(
+        width: 480,
+        child: SingleChildScrollView(
+          child: Column(
+            crossAxisAlignment: CrossAxisAlignment.stretch,
+            mainAxisSize: MainAxisSize.min,
+            children: [
+              Text(l.dPasteHelp),
+              const SizedBox(height: 12),
+              TextField(
+                controller: text,
+                maxLines: 6,
+                decoration: InputDecoration(labelText: l.dBankDetails),
+                onChanged: (_) => setState(() => result = null),
+              ),
+              if (result != null) ...[
+                const SizedBox(height: 12),
+                if (result!.conflicts.isNotEmpty) Text(l.dPasteConflict),
+                for (final e in result!.values.entries)
+                  Text('${labels[e.key]}: ${e.value}'),
+              ],
+            ],
+          ),
+        ),
+      ),
+      actions: [
+        TextButton(
+          onPressed: () => Navigator.pop(context),
+          child: Text(l.wClose),
+        ),
+        FilledButton(
+          onPressed: result == null
+              ? () => setState(() => result = BankPaste.parse(text.text))
+              : result!.values.isEmpty
+              ? null
+              : () => Navigator.pop(context, result),
+          child: Text(result == null ? l.dPasteReview : l.dPasteApply),
+        ),
+      ],
+    );
+  }
+}

frontend/app/lib/l10n/en.arb

@@ -289,5 +289,95 @@
         "type": "int"
       }
     }
+  },
+  "dTitle": "Payout methods",
+  "dAdd": "Add payout method",
+  "dChoose": "Payout destination",
+  "dNew": "Use a new destination",
+  "dSave": "Save payout method",
+  "dContinue": "Continue",
+  "dSaveFuture": "Save for future payouts",
+  "dSaveHelp": "Continue will also save this destination.",
+  "dNickname": "Name for this method (optional)",
+  "dSaved": "Payout method saved.",
+  "dSaveFailed": "Couldn’t save these details. Your input is still here.",
+  "dRetrySave": "Retry saving",
+  "dWithoutSave": "Continue without saving",
+  "dUncertain": "We couldn’t confirm saving. This method may already be saved.",
+  "dCheckSave": "Check save status",
+  "dDuplicate": "This destination is already saved. Use the existing method.",
+  "dUseExisting": "Use existing method",
+  "dCrypto": "Crypto address",
+  "dCard": "Bank card",
+  "dBank": "Russian bank account",
+  "dType": "Destination type",
+  "dSearch": "Search saved methods",
+  "dEmpty": "No saved methods in this category.",
+  "dNoMatches": "No matching methods.",
+  "dEligible": "Available",
+  "dTemporary": "Temporarily unavailable for this payout.",
+  "dAction": "Action required",
+  "dUnsupported": "This method isn’t supported for this payout.",
+  "dUnavailable": "Couldn’t load methods. Try again.",
+  "dNoCapabilities": "No destination types are currently available.",
+  "dDemo": "Demo destinations — saving lasts until reload. No real payout or card collection is connected.",
+  "dAsset": "Receiving asset",
+  "dNetwork": "Network",
+  "dAddress": "Wallet address",
+  "dMemo": "Memo / destination tag",
+  "dNoMemo": "No memo / tag",
+  "dCryptoHelp": "Use the network supported by your receiving wallet. A valid address format does not guarantee delivery.",
+  "dHolder": "Account holder",
+  "dFirst": "First name",
+  "dLast": "Last name",
+  "dPatronymic": "Patronymic (optional)",
+  "dBankDetails": "Bank details",
+  "dBankSearch": "Bank name or BIK",
+  "dAccount": "20-digit account number",
+  "dCorrespondent": "Correspondent account",
+  "dChangeBank": "Change bank",
+  "dBankUnknown": "Bank not found. Check the name or BIK.",
+  "dBankFailure": "Bank directory is unavailable. Your input is preserved.",
+  "dBankChanged": "Bank details changed. Review them and add a replacement destination.",
+  "dPaste": "Paste bank details",
+  "dPasteHelp": "Paste labelled bank details. Review recognized values before applying them.",
+  "dPasteReview": "Review recognized details",
+  "dPasteApply": "Use these details",
+  "dPasteConflict": "Conflicting values were found. Correct the affected fields in the form.",
+  "dInvalid": "Check the entered details and correct the highlighted field.",
+  "dCardDemo": "Choose a simulated secure card capture. Do not enter a real card number.",
+  "dCardReady": "Demo card •••• 4242",
+  "dCardRecover": "Demo card requiring renewed authorization",
+  "dCardExpired": "This card has expired. Add a replacement card.",
+  "dAuthorization": "Authorization needs updating. Follow the service-supported recovery or add a replacement.",
+  "dRemoved": "This method was removed. Your draft is preserved. Choose a destination to continue.",
+  "dConflict": "This method changed in another session. Refresh and review the latest version.",
+  "dRename": "Rename",
+  "dRemove": "Remove",
+  "dReplace": "Add replacement",
+  "dRemoveTitle": "Remove payout method?",
+  "dRemoveHelp": "Removed methods cannot be used for new payouts. Submitted payouts and required financial records are retained.",
+  "dDetails": "Destination details",
+  "dReload": "Refresh methods",
+  "dSelect": "Select destination",
+  "dQuoteChanged": "Payout terms changed. Your draft is preserved. Select a destination and review a new quote.",
+  "dOwn": "Use a wallet, card, or account that belongs to you.",
+  "dSavedIneligible": "Saved. This method is unavailable for the current payout.",
+  "dSaveFailedLabel": "Saving failed",
+  "dNoEligible": "No methods are available for this payout. You can add a destination or refresh.",
+  "dDemoTerms": "Demo receiving amounts use a fixed 1:1 ratio. No real payout is made.",
+  "dTiming": "Expected processing time: {seconds} seconds",
+  "@dTiming": {
+    "placeholders": {
+      "seconds": {
+        "type": "int"
       }
     }
+  },
+  "dBik": "BIK",
+  "dBankMismatch": "Pasted bank details differ from the selected bank. Check the details before continuing.",
+  "dManagementUnavailable": "Saving payout methods isn’t available yet. You can still use your configured payout destination.",
+  "dUpdateAuthorization": "Update authorization",
+  "dAuthorizationUpdated": "Authorization updated.",
+  "dReplacementRequired": "Couldn’t confirm this is the same card. Add a replacement destination."
+}

frontend/app/lib/l10n/ru.arb

@@ -289,5 +289,95 @@
         "type": "int"
       }
     }
+  },
+  "dTitle": "Способы вывода",
+  "dAdd": "Добавить способ вывода",
+  "dChoose": "Реквизиты для вывода",
+  "dNew": "Использовать новые реквизиты",
+  "dSave": "Сохранить способ вывода",
+  "dContinue": "Продолжить",
+  "dSaveFuture": "Сохранить для будущих выводов",
+  "dSaveHelp": "При продолжении реквизиты также будут сохранены.",
+  "dNickname": "Название способа вывода (необязательно)",
+  "dSaved": "Способ вывода сохранён.",
+  "dSaveFailed": "Не удалось сохранить реквизиты. Введённые данные остались в форме.",
+  "dRetrySave": "Повторить сохранение",
+  "dWithoutSave": "Продолжить без сохранения",
+  "dUncertain": "Не удалось подтвердить сохранение. Возможно, способ уже сохранён.",
+  "dCheckSave": "Проверить статус сохранения",
+  "dDuplicate": "Эти реквизиты уже сохранены. Используйте существующий способ.",
+  "dUseExisting": "Использовать существующий способ",
+  "dCrypto": "Криптоадрес",
+  "dCard": "Банковская карта",
+  "dBank": "Российский банковский счёт",
+  "dType": "Тип реквизитов",
+  "dSearch": "Поиск сохранённых способов",
+  "dEmpty": "В этой категории нет сохранённых способов.",
+  "dNoMatches": "Подходящие способы не найдены.",
+  "dEligible": "Доступно",
+  "dTemporary": "Временно недоступно для этого вывода.",
+  "dAction": "Требуется действие",
+  "dUnsupported": "Этот способ не поддерживается для данного вывода.",
+  "dUnavailable": "Не удалось загрузить способы. Повторите попытку.",
+  "dNoCapabilities": "Сейчас нет доступных типов реквизитов.",
+  "dDemo": "Демонстрационные реквизиты — сохранение действует до перезагрузки. Реальный вывод и ввод карт не подключены.",
+  "dAsset": "Получаемый актив",
+  "dNetwork": "Сеть",
+  "dAddress": "Адрес кошелька",
+  "dMemo": "Memo / тег назначения",
+  "dNoMemo": "Без memo / тега",
+  "dCryptoHelp": "Выберите сеть, поддерживаемую кошельком получателя. Верный формат адреса не гарантирует зачисление.",
+  "dHolder": "Владелец счёта",
+  "dFirst": "Имя",
+  "dLast": "Фамилия",
+  "dPatronymic": "Отчество (необязательно)",
+  "dBankDetails": "Банковские реквизиты",
+  "dBankSearch": "Название банка или БИК",
+  "dAccount": "20-значный номер счёта",
+  "dCorrespondent": "Корреспондентский счёт",
+  "dChangeBank": "Изменить банк",
+  "dBankUnknown": "Банк не найден. Проверьте название или БИК.",
+  "dBankFailure": "Справочник банков недоступен. Введённые данные сохранены.",
+  "dBankChanged": "Банковские реквизиты изменились. Проверьте их и добавьте новые реквизиты.",
+  "dPaste": "Вставить банковские реквизиты",
+  "dPasteHelp": "Вставьте реквизиты с названиями полей. Проверьте распознанные значения перед применением.",
+  "dPasteReview": "Проверить распознанные реквизиты",
+  "dPasteApply": "Использовать эти реквизиты",
+  "dPasteConflict": "Найдены противоречивые значения. Исправьте соответствующие поля в форме.",
+  "dInvalid": "Проверьте введённые реквизиты и исправьте выделенное поле.",
+  "dCardDemo": "Выберите демонстрационный результат безопасного ввода карты. Не вводите настоящий номер карты.",
+  "dCardReady": "Демо-карта •••• 4242",
+  "dCardRecover": "Демо-карта с истёкшей авторизацией",
+  "dCardExpired": "Срок действия карты истёк. Добавьте новую карту.",
+  "dAuthorization": "Необходимо обновить авторизацию. Используйте доступное восстановление или добавьте новые реквизиты.",
+  "dRemoved": "Этот способ удалён. Черновик сохранён. Выберите реквизиты для продолжения.",
+  "dConflict": "Этот способ изменён в другой сессии. Обновите и проверьте актуальную версию.",
+  "dRename": "Переименовать",
+  "dRemove": "Удалить",
+  "dReplace": "Добавить новые реквизиты",
+  "dRemoveTitle": "Удалить способ вывода?",
+  "dRemoveHelp": "Удалённые способы недоступны для новых выводов. Отправленные заявки и обязательные финансовые записи сохраняются.",
+  "dDetails": "Реквизиты",
+  "dReload": "Обновить способы",
+  "dSelect": "Выбрать реквизиты",
+  "dQuoteChanged": "Условия вывода изменились. Черновик сохранён. Выберите реквизиты и проверьте новую котировку.",
+  "dOwn": "Используйте принадлежащий вам кошелёк, карту или счёт.",
+  "dSavedIneligible": "Сохранено. Этот способ недоступен для текущего вывода.",
+  "dSaveFailedLabel": "Ошибка сохранения",
+  "dNoEligible": "Для этого вывода нет доступных способов. Добавьте реквизиты или обновите список.",
+  "dDemoTerms": "Демонстрационные суммы зачисления рассчитаны по фиксированному курсу 1:1. Реальный вывод не выполняется.",
+  "dTiming": "Ожидаемое время обработки: {seconds} сек.",
+  "@dTiming": {
+    "placeholders": {
+      "seconds": {
+        "type": "int"
       }
     }
+  },
+  "dBik": "БИК",
+  "dBankMismatch": "Вставленные реквизиты отличаются от выбранного банка. Проверьте их перед продолжением.",
+  "dManagementUnavailable": "Сохранение способов вывода пока недоступно. Вы можете использовать ранее настроенные реквизиты для вывода.",
+  "dUpdateAuthorization": "Обновить авторизацию",
+  "dAuthorizationUpdated": "Авторизация обновлена.",
+  "dReplacementRequired": "Не удалось подтвердить, что это та же карта. Добавьте новые реквизиты."
+}

frontend/app/lib/main.dart

@@ -37,6 +37,7 @@ class SxchngeApp extends StatefulWidget {
     this.identityService,
     this.limitsService,
     this.walletService,
+    this.destinationService,
     this.twoFactorService,
     this.photoService = const FilePhotoService(),
     this.loginService = const DummyLoginService(),
@@ -49,6 +50,7 @@ class SxchngeApp extends StatefulWidget {
   final IdentityService? identityService;
   final LimitsService? limitsService;
   final WalletService? walletService;
+  final DestinationService? destinationService;
   final TwoFactorService? twoFactorService;
   final PhotoService photoService;
   final LoginService loginService;
@@ -89,10 +91,17 @@ class _SxchngeAppState extends State<SxchngeApp> {
               initialLocale: _locale.locale.languageCode,
               factors: _authFactors,
             ));
+  late final _destinationService =
+      widget.destinationService ??
+      (_walletService.isSimulated && _walletService is DummyWalletService
+          ? _walletService.destinations
+          : const UnavailableDestinationService());
+  late final _destinations = DestinationsProvider(_destinationService);
   late final _wallet = WalletProvider(
     _walletService,
     _analytics,
     factors: _factors,
+    destinations: _destinationService,
   );
   late final _limits =
       widget.limitsService ??
@@ -131,6 +140,7 @@ class _SxchngeAppState extends State<SxchngeApp> {
     if (customer != _walletCustomer) {
       _walletCustomer = customer;
       _wallet.reset();
+      _destinations.reset();
     }
     final path = _router.routeInformationProvider.value.uri.path;
     if (path == '/' && _previousPath != '/' && _previousPath != '/two-factor') {
@@ -145,6 +155,7 @@ class _SxchngeAppState extends State<SxchngeApp> {
     _router.dispose();
     _journeys.dispose();
     _wallet.dispose();
+    _destinations.dispose();
     if (_walletService is BackendWalletService) {
       _walletService.close();
     }
@@ -161,6 +172,7 @@ class _SxchngeAppState extends State<SxchngeApp> {
   Widget build(BuildContext context) => MultiProvider(
     providers: [
       ChangeNotifierProvider.value(value: _wallet),
+      ChangeNotifierProvider.value(value: _destinations),
       ChangeNotifierProvider.value(value: _security),
       Provider<TwoFactorService>.value(value: _factors),
       Provider<JourneyRecorder>.value(value: _journeys),

frontend/app/lib/routing/router.dart

@@ -7,6 +7,7 @@ import 'package:go_router/go_router.dart';
 import 'package:sxchnge_wallet/sxchnge_wallet.dart';
 
 import '../auth/page.dart';
+import '../destinations/list.dart';
 import '../kyc/page.dart';
 import '../security/challenge.dart';
 import '../verification/page.dart';
@@ -82,6 +83,12 @@ GoRouter createAppRouter({bool Function()? authenticated}) {
           GoRoute(
             path: '/settings',
             builder: (context, state) => const SettingsPage(),
+            routes: [
+              GoRoute(
+                path: 'payout-methods',
+                builder: (context, state) => const DestinationsPage(),
+              ),
+            ],
           ),
           GoRoute(
             path: '/top-up',

frontend/app/lib/workspace/copy.dart

@@ -48,6 +48,7 @@ String fundsText(
         _ => l.wFailedOutgoing,
       };
 String walletError(AppLocalizations l, WalletError e) => switch (e) {
+  WalletError.destinationChanged => l.dQuoteChanged,
   WalletError.invalidAmount => l.wInvalidAmount,
   WalletError.insufficientFunds => l.wInsufficient,
   WalletError.limitExceeded => l.wLimitError,

frontend/app/lib/workspace/settings.dart

@@ -106,6 +106,15 @@ class SettingsPage extends StatelessWidget {
                 ),
               ),
               const SizedBox(height: 16),
+              Card(
+                child: ListTile(
+                  leading: const Icon(Icons.account_balance_outlined),
+                  title: Text(l.dTitle),
+                  trailing: const Icon(Icons.chevron_right),
+                  onTap: () => context.push('/settings/payout-methods'),
+                ),
+              ),
+              const SizedBox(height: 16),
               const SecuritySettings(),
               const SizedBox(height: 20),
               TextButton(

frontend/app/lib/workspace/summary.dart

@@ -1,3 +1,5 @@
+import 'dart:math';
+
 import 'package:flutter/material.dart';
 
 import 'package:intl/intl.dart';
@@ -6,6 +8,8 @@ import 'package:provider/provider.dart';
 
 import 'package:sxchnge_wallet/sxchnge_wallet.dart';
 
+import '../destinations/details.dart';
+
 import 'copy.dart';
 
 import '../generated/i18n/app_localizations.dart';
@@ -49,12 +53,22 @@ class TransferSummary extends StatelessWidget {
               q.request.kind == TransferKind.payout
                   ? l.wRecipientGets
                   : l.wCredit,
-              money(context, b, q.credit),
+              q.payoutTerms == null
+                  ? money(context, b, q.credit)
+                  : '${NumberFormat.decimalPatternDigits(locale: Localizations.localeOf(context).toLanguageTag(), decimalDigits: q.payoutTerms!.precision).format(q.payoutTerms!.amount / pow(10, q.payoutTerms!.precision))} ${q.payoutTerms!.assetLabel}',
               large: true,
             ),
+            if (q.payoutTerms != null) ...[
+              const SizedBox(height: 12),
+              Text(l.dTiming(q.payoutTerms!.expectedSeconds)),
+              if (p.service.isSimulated) Text(l.dDemoTerms),
+            ],
             if (q.request.kind == TransferKind.payout) ...[
               const Divider(height: 32),
               Text(l.wRecipient),
+              if (q.payoutSnapshot != null)
+                DestinationDetailsView(details: q.payoutSnapshot!)
+              else
                 SelectableText(q.request.recipient),
             ],
           ],

frontend/app/lib/workspace/transfer.dart

@@ -11,6 +11,7 @@ import 'package:sxchnge_auth/sxchnge_auth.dart';
 import 'package:sxchnge_wallet/sxchnge_wallet.dart';
 
 import '../security/challenge.dart';
+import '../destinations/list.dart';
 
 import 'copy.dart';
 import 'summary.dart';
@@ -32,7 +33,7 @@ class TransferPageState extends State<TransferPage> {
     source: widget.source,
   );
   final _amount = TextEditingController();
-  final _recipient = TextEditingController();
+
   final _focus = FocusNode();
   final _content = GlobalKey();
   Timer? _timer;
@@ -41,7 +42,13 @@ class TransferPageState extends State<TransferPage> {
   void initState() {
     super.initState();
     WidgetsBinding.instance.addPostFrameCallback((_) {
-      if (mounted) _provider.addListener(_changed);
+      if (mounted) {
+        _provider.addListener(_changed);
+        final destinations = context.read<DestinationsProvider>();
+        if (destinations.capabilities == null && !destinations.loading) {
+          unawaited(destinations.refresh());
+        }
+      }
     });
     _timer = Timer.periodic(const Duration(seconds: 1), (_) {
       if (mounted && _provider.quote != null) setState(() {});
@@ -118,7 +125,7 @@ class TransferPageState extends State<TransferPage> {
     _provider.removeListener(_changed);
     _provider.dispose();
     _amount.dispose();
-    _recipient.dispose();
+
     _focus.dispose();
     super.dispose();
   }
@@ -134,14 +141,16 @@ class TransferPageState extends State<TransferPage> {
       final accounts = wallet.data?.accounts ?? [];
       final source = wallet.account(p.source);
       final live = !wallet.service.isSimulated;
+      final destinations = context.watch<DestinationsProvider>();
+      final legacyPayout =
+          live &&
+          !(destinations.capabilities?.types.isNotEmpty ?? false) &&
+          destinations.methods.isEmpty;
       final expiresIn =
           p.quote?.expiresAt.difference(DateTime.now()).inSeconds ?? 0;
       final unavailableMethod =
           live &&
-          ((widget.kind == TransferKind.payout &&
+          ((widget.kind == TransferKind.topUp && !(source?.canFund ?? false)));
-                  (source?.payoutMethod.isEmpty ?? true)) ||
-              (widget.kind == TransferKind.topUp &&
-                  !(source?.canFund ?? false)));
       return SingleChildScrollView(
         padding: const EdgeInsets.all(24),
         child: Center(
@@ -235,7 +244,11 @@ class TransferPageState extends State<TransferPage> {
                           FilledButton(
                             key: const ValueKey('transfer-confirm'),
                             onPressed: p.busy ? null : _confirm,
-                            child: Text(l.wConfirm),
+                            child: Text(
+                              widget.kind == TransferKind.payout
+                                  ? '${l.wPayout} ${money(context, source!, p.quote!.debit)}'
+                                  : l.wConfirm,
+                            ),
                           ),
                         TextButton(
                           onPressed: p.busy ? null : p.edit,
@@ -316,23 +329,66 @@ class TransferPageState extends State<TransferPage> {
                           ),
                           if (widget.kind == TransferKind.payout) ...[
                             const SizedBox(height: 20),
-                            if (live && source?.payoutMethod.isNotEmpty == true)
+                            if (legacyPayout) ...[
-                              InputDecorator(
+                              if (source?.payoutMethod.isNotEmpty == true)
-                                decoration: InputDecoration(
+                                OutlinedButton.icon(
-                                  labelText: l.wRecipient,
+                                  key: const ValueKey(
+                                    'choose-configured-destination',
                                   ),
-                                child: Text(source!.payoutLabel),
+                                  icon: const Icon(
+                                    Icons.account_balance_outlined,
                                   ),
-                            if (!live)
+                                  label: Text(source!.payoutLabel),
-                              TextField(
+                                  onPressed: p.busy
-                                key: const ValueKey('transfer-recipient'),
+                                      ? null
-                                controller: _recipient,
+                                      : () => p.change(
-                                enabled: !p.busy,
+                                          recipient: source.payoutMethod,
-                                decoration: InputDecoration(
+                                          payoutLabel: source.payoutLabel,
-                                  labelText: l.wRecipient,
-                                  hintText: l.wRecipientHint,
                                         ),
-                                onChanged: (v) => p.change(recipient: v),
+                                ),
+                              if (source?.payoutMethod.isEmpty ?? true)
+                                Text(l.wNoPayoutMethod),
+                            ] else
+                              OutlinedButton.icon(
+                                key: const ValueKey(
+                                  'choose-payout-destination',
+                                ),
+                                icon: const Icon(
+                                  Icons.account_balance_wallet_outlined,
+                                ),
+                                label: Text(
+                                  p.payoutDestination == null
+                                      ? l.dSelect
+                                      : p.payoutLabel,
+                                ),
+                                onPressed: p.busy
+                                    ? null
+                                    : () async {
+                                        final selected =
+                                            await Navigator.push<
+                                              DestinationInput
+                                            >(
+                                              context,
+                                              MaterialPageRoute(
+                                                builder: (_) =>
+                                                    DestinationsPage(
+                                                      payoutContext:
+                                                          PayoutContext(
+                                                            p.source,
+                                                            amount: source
+                                                                ?.parse(
+                                                                  p.amount,
+                                                                ),
+                                                          ),
+                                                    ),
+                                              ),
+                                            );
+                                        if (!context.mounted ||
+                                            selected == null) {
+                                          return;
+                                        }
+                                        await p.selectPayout(selected);
+                                      },
                               ),
                           ],
                           if (unavailableMethod) ...[
@@ -346,7 +402,13 @@ class TransferPageState extends State<TransferPage> {
                           const SizedBox(height: 28),
                           FilledButton(
                             key: const ValueKey('transfer-review'),
-                            onPressed: p.busy || unavailableMethod
+                            onPressed:
+                                p.busy ||
+                                    unavailableMethod ||
+                                    (widget.kind == TransferKind.payout &&
+                                        (legacyPayout
+                                            ? p.recipient.isEmpty
+                                            : p.payoutDestination == null))
                                 ? null
                                 : p.review,
                             child: Text(l.wReview),

frontend/app/test/destination_helpers.dart

@@ -0,0 +1,31 @@
+import 'package:flutter/material.dart';
+
+import 'package:flutter_test/flutter_test.dart';
+
+import 'package:sxchnge_wallet/sxchnge_wallet.dart';
+
+const testDestination = CryptoDestination(
+  assetId: 'demo:ethereum:native',
+  networkId: 'eip155:1',
+  address: '0x1234567890123456789012345678901234567890',
+  assetLabel: 'ETH',
+  networkLabel: 'Ethereum',
+);
+Future<void> seedDestination(DummyDestinationService service) async {
+  await service.create(
+    testDestination,
+    'Test wallet',
+    'test-destination-creation',
+  );
+}
+
+Future<void> selectPayout(WidgetTester t) async {
+  final button = find.byKey(const ValueKey('choose-payout-destination'));
+  await t.ensureVisible(button);
+  await t.tap(button);
+  await t.pumpAndSettle();
+  final row = find.text('Test wallet');
+  await t.ensureVisible(row);
+  await t.tap(row);
+  await t.pumpAndSettle();
+}

frontend/app/test/destinations_test.dart

@@ -0,0 +1,245 @@
+import 'package:flutter/material.dart';
+
+import 'package:flutter_test/flutter_test.dart';
+
+import 'package:sxchnge_analytics/sxchnge_analytics.dart';
+
+import 'package:sxchnge_kyc/sxchnge_kyc.dart';
+
+import 'package:sxchnge_wallet/sxchnge_wallet.dart';
+
+import 'package:sxchnge_app/main.dart';
+import 'package:sxchnge_app/providers/locale.dart';
+
+import 'destination_helpers.dart';
+
+Future<void> click(WidgetTester t, Finder finder) async {
+  await t.ensureVisible(finder);
+  await t.pumpAndSettle();
+  await t.tap(finder);
+  await t.pumpAndSettle();
+}
+
+Future<DummyWalletService> open(
+  WidgetTester t, {
+  String path = '/settings/payout-methods',
+  String locale = 'en',
+  DummyDestinationService? destinations,
+  DummyAnalyticsService? analytics,
+}) async {
+  t.platformDispatcher.defaultRouteNameTestValue = path;
+  addTearDown(t.platformDispatcher.clearDefaultRouteNameTestValue);
+  final wallet = DummyWalletService(
+    DummyIdentityService(delay: Duration.zero),
+    delay: Duration.zero,
+    destinations: destinations,
+    initialLocale: locale,
+    settlement: Duration.zero,
+  );
+  await t.pumpWidget(
+    SxchngeApp(
+      walletService: wallet,
+      analyticsService: analytics,
+      localeProvider: LocaleProvider(initialLocale: Locale(locale)),
+    ),
+  );
+  await t.pumpAndSettle();
+  addTearDown(() => t.pumpWidget(const SizedBox.shrink()));
+  return wallet;
+}
+
+Future<void> cryptoForm(WidgetTester t, {bool payout = false}) async {
+  await click(
+    t,
+    find.text(payout ? 'Use a new destination' : 'Add payout method').first,
+  );
+  await click(t, find.byType(DropdownButtonFormField<DestinationType>));
+  await click(t, find.text('Crypto address').last);
+  await click(t, find.byKey(const ValueKey('asset-null')));
+  await click(t, find.text('ETH').last);
+  await click(t, find.byType(DropdownButtonFormField<String>).last);
+  await click(t, find.text('Ethereum').last);
+  await t.enterText(
+    find.byKey(const ValueKey('destination-address')),
+    testDestination.address,
+  );
+  await t.pump();
+}
+
+void main() {
+  testWidgets('Settings saves without nickname and exposes renamed method', (
+    t,
+  ) async {
+    final wallet = await open(t);
+    await cryptoForm(t);
+    expect(find.text('Save for future payouts'), findsNothing);
+    await click(t, find.byKey(const ValueKey('destination-continue')));
+    expect((await wallet.destinations.list()).length, 1);
+    expect(find.textContaining('ETH · Ethereum'), findsOneWidget);
+    await click(t, find.textContaining('ETH · Ethereum'));
+    await t.enterText(
+      find.byKey(const ValueKey('destination-nickname')),
+      'My own wallet',
+    );
+    await click(t, find.text('Rename'));
+    expect((await wallet.destinations.list()).single.nickname, 'My own wallet');
+    await click(t, find.text('Remove'));
+    expect(find.textContaining('Submitted payouts'), findsOneWidget);
+    await click(t, find.widgetWithText(FilledButton, 'Remove'));
+    expect(await wallet.destinations.list(), isEmpty);
+    expect(t.takeException(), isNull);
+  });
+  testWidgets('new one-time payout keeps saving unchecked and never persists', (
+    t,
+  ) async {
+    final wallet = await open(t, path: '/payout');
+    await t.enterText(find.byKey(const ValueKey('transfer-amount')), '5');
+    await click(t, find.byKey(const ValueKey('choose-payout-destination')));
+    await cryptoForm(t, payout: true);
+    expect(
+      t.widget<CheckboxListTile>(find.byType(CheckboxListTile)).value,
+      isFalse,
+    );
+    expect(find.byKey(const ValueKey('destination-nickname')), findsNothing);
+    await click(t, find.byKey(const ValueKey('destination-continue')));
+    await click(t, find.byKey(const ValueKey('transfer-review')));
+    expect(find.textContaining(testDestination.address), findsOneWidget);
+    await click(t, find.byKey(const ValueKey('transfer-confirm')));
+    expect(find.byKey(const ValueKey('operation-completed')), findsOneWidget);
+    expect(await wallet.destinations.list(), isEmpty);
+  });
+  testWidgets(
+    'optional saving failure permits explicit one-time continuation',
+    (t) async {
+      final service = DummyDestinationService();
+      final wallet = await open(t, path: '/payout', destinations: service);
+      await t.enterText(find.byKey(const ValueKey('transfer-amount')), '5');
+      await click(t, find.byKey(const ValueKey('choose-payout-destination')));
+      await cryptoForm(t, payout: true);
+      await click(t, find.text('Save for future payouts'));
+      service.nextSaveError = DestinationIssue.conflict;
+      await click(t, find.byKey(const ValueKey('destination-continue')));
+      expect(find.textContaining('Couldn’t save'), findsOneWidget);
+      await click(t, find.text('Continue without saving'));
+      await click(t, find.byKey(const ValueKey('transfer-review')));
+      await click(t, find.byKey(const ValueKey('transfer-confirm')));
+      expect(find.byKey(const ValueKey('operation-completed')), findsOneWidget);
+      expect(await wallet.destinations.list(), isEmpty);
+    },
+  );
+  testWidgets(
+    'saved destination is never selected automatically and removal preserves amount',
+    (t) async {
+      final service = DummyDestinationService();
+      await seedDestination(service);
+      final wallet = await open(t, path: '/payout', destinations: service);
+      await t.enterText(find.byKey(const ValueKey('transfer-amount')), '5');
+      expect(
+        t
+            .widget<FilledButton>(find.byKey(const ValueKey('transfer-review')))
+            .onPressed,
+        isNull,
+      );
+      await selectPayout(t);
+      await click(t, find.byKey(const ValueKey('transfer-review')));
+      final d = (await service.list()).single;
+      await service.remove(d.id, d.metadataRevision, d.executionRevision);
+      await click(t, find.byKey(const ValueKey('transfer-confirm')));
+      expect(find.textContaining('Payout terms changed'), findsOneWidget);
+      expect(find.text('5'), findsOneWidget);
+      expect((await t.runAsync(wallet.fetch))!.operations, isEmpty);
+    },
+  );
+  for (final locale in ['en', 'ru']) {
+    testWidgets('all method forms fit $locale at 320px with large text', (
+      t,
+    ) async {
+      t.view.physicalSize = const Size(320, 1100);
+      t.view.devicePixelRatio = 1;
+      t.platformDispatcher.textScaleFactorTestValue = 1.6;
+      addTearDown(t.view.resetPhysicalSize);
+      addTearDown(t.view.resetDevicePixelRatio);
+      addTearDown(t.platformDispatcher.clearTextScaleFactorTestValue);
+      await open(t, locale: locale);
+      await click(
+        t,
+        find
+            .text(
+              locale == 'en' ? 'Add payout method' : 'Добавить способ вывода',
+            )
+            .first,
+      );
+      for (final name
+          in locale == 'en'
+              ? ['Crypto address', 'Bank card', 'Russian bank account']
+              : [
+                  'Криптоадрес',
+                  'Банковская карта',
+                  'Российский банковский счёт',
+                ]) {
+        await click(t, find.byType(DropdownButtonFormField<DestinationType>));
+        await click(t, find.text(name).last);
+        expect(t.takeException(), isNull);
+      }
+    });
+  }
+  testWidgets('semantic save outcomes contain no destination fields', (
+    t,
+  ) async {
+    final analytics = DummyAnalyticsService();
+    await open(t, analytics: analytics);
+    await cryptoForm(t);
+    await click(t, find.byKey(const ValueKey('destination-continue')));
+    await t.pumpAndSettle();
+    final events = analytics.events
+        .where((e) => e.kind == JourneyKind.destination)
+        .toList();
+    expect(
+      events.any(
+        (e) =>
+            e.step == JourneyStep.destinationSave &&
+            e.signal == JourneySignal.simulated,
+      ),
+      isTrue,
+    );
+    expect(
+      events.map((e) => e.properties.toString()).join(),
+      isNot(contains(testDestination.address)),
+    );
+  });
+
+  testWidgets(
+    'binding recovery uses secure capture and preserves the saved card',
+    (t) async {
+      final service = DummyDestinationService();
+      final created = await service.create(
+        const CardDestination(
+          capture: 'demo-card-recover',
+          brand: '',
+          last4: '',
+          expiryMonth: 0,
+          expiryYear: 0,
+        ),
+        'Own card',
+        'creation-key-000001',
+      );
+      await open(t, destinations: service);
+      await click(t, find.text('Own card'));
+      await click(t, find.text('Update authorization'));
+      expect(find.byKey(const ValueKey('destination-nickname')), findsNothing);
+      await click(t, find.text('Demo card •••• 4242'));
+      await click(t, find.byKey(const ValueKey('destination-continue')));
+      final saved = await service.get(created.destinationId);
+      expect(saved.executionRevision, 2);
+      expect(saved.nickname, 'Own card');
+      expect((await service.list()).length, 1);
+      expect(
+        (await service.assess(
+          saved.input,
+          const PayoutContext('eur'),
+        )).eligible,
+        isTrue,
+      );
+    },
+  );
+}

frontend/app/test/payout_backend_test.dart

@@ -76,6 +76,14 @@ void main() {
         await t.ensureVisible(review);
         if (hasMethod) {
           expect(find.text(destinationLabel), findsOneWidget);
+          final choose = find.byKey(
+            const ValueKey('choose-configured-destination'),
+          );
+          expect(t.widget<FilledButton>(review).onPressed, isNull);
+          await t.ensureVisible(choose);
+          await t.tap(choose);
+          await t.pumpAndSettle();
+          await t.ensureVisible(review);
           await t.tap(review);
           await t.pumpAndSettle();
           expect(wallet.received, 'method-ref');

frontend/app/test/two_factor_test.dart

@@ -6,9 +6,15 @@ import 'package:sxchnge_analytics/sxchnge_analytics.dart';
 
 import 'package:sxchnge_auth/sxchnge_auth.dart';
 
+import 'package:sxchnge_kyc/sxchnge_kyc.dart';
+
+import 'package:sxchnge_wallet/sxchnge_wallet.dart';
+
 import 'package:sxchnge_app/main.dart';
 import 'package:sxchnge_app/providers/locale.dart';
 
+import 'destination_helpers.dart';
+
 Future<void> tapFactor(WidgetTester t, String key) async {
   final finder = find.byKey(ValueKey(key));
   await t.ensureVisible(finder);
@@ -31,8 +37,16 @@ Future<DummyTwoFactorService> openFactor(
     delay: Duration.zero,
     method: method,
   );
+  final wallet = DummyWalletService(
+    DummyIdentityService(delay: Duration.zero),
+    factors: service,
+    initialLocale: locale,
+    delay: Duration.zero,
+  );
+  await seedDestination(wallet.destinations);
   await t.pumpWidget(
     SxchngeApp(
+      walletService: wallet,
       twoFactorService: service,
       analyticsService: analytics,
       localeProvider: LocaleProvider(initialLocale: Locale(locale)),
@@ -174,10 +188,7 @@ void main() {
         await openFactor(t, path: '/$kind', enabled: true);
         await t.enterText(find.byKey(const ValueKey('transfer-amount')), '10');
         if (kind == 'payout') {
-          await t.enterText(
+          await selectPayout(t);
-            find.byKey(const ValueKey('transfer-recipient')),
-            'Sample recipient',
-          );
         }
         await tapFactor(t, 'transfer-review');
         await tapFactor(t, 'transfer-confirm');

frontend/app/test/workspace_test.dart

@@ -11,6 +11,8 @@ import 'package:sxchnge_wallet/sxchnge_wallet.dart';
 import 'package:sxchnge_app/main.dart';
 import 'package:sxchnge_app/providers/locale.dart';
 
+import 'destination_helpers.dart';
+
 Future<void> tap(WidgetTester t, Finder f) async {
   await t.ensureVisible(f);
   await t.tap(f);
@@ -32,6 +34,7 @@ Future<DummyWalletService> open(
     settlement: settlement,
     initialLocale: locale,
   );
+  await seedDestination(service.destinations);
   await t.pumpWidget(
     SxchngeApp(
       identityService: identity,
@@ -78,10 +81,7 @@ void main() {
     expect(find.byKey(const ValueKey('operation-completed')), findsOneWidget);
     await tap(t, find.text('Pay out').last);
     await t.enterText(find.byKey(const ValueKey('transfer-amount')), '5');
-    await t.enterText(
+    await selectPayout(t);
-      find.byKey(const ValueKey('transfer-recipient')),
-      'Sample recipient',
-    );
     await tap(t, find.byKey(const ValueKey('transfer-review')));
     expect(find.text('Recipient receives'), findsOneWidget);
     await tap(t, find.byKey(const ValueKey('transfer-confirm')));
@@ -101,10 +101,7 @@ void main() {
       );
       s.failNextOperation = true;
       await t.enterText(find.byKey(const ValueKey('transfer-amount')), '10');
-      await t.enterText(
+      await selectPayout(t);
-        find.byKey(const ValueKey('transfer-recipient')),
-        'Sample recipient',
-      );
       await tap(t, find.byKey(const ValueKey('transfer-review')));
       await tap(t, find.byKey(const ValueKey('transfer-confirm')));
       // Settlement is service-owned; refresh after the simulated processing period.

frontend/packages/sxchnge_analytics/lib/sxchnge_analytics.dart

@@ -11,8 +11,11 @@ enum JourneyKind {
   exchange,
   payout,
   security,
+  destination,
 }
 
+enum DestinationResolution { created, duplicate }
+
 enum JourneyStep {
   login,
   signup,
@@ -23,6 +26,10 @@ enum JourneyStep {
   kycSelfie,
   kycSubmission,
   kycStatus,
+  destinationDraft,
+  destinationSave,
+  destinationReconciliation,
+  destinationBinding,
   transferDraft,
   transferQuote,
   transferSubmission,
@@ -78,6 +85,7 @@ class AnalyticsEvent {
     required this.sequence,
     required this.elapsedMs,
     this.step,
+    this.resolution,
     this.operation,
     this.failure,
     this.exit,
@@ -90,6 +98,7 @@ class AnalyticsEvent {
   final JourneyKind kind;
   final JourneySignal signal;
   final JourneyStep? step;
+  final DestinationResolution? resolution;
   final JourneyFailure? failure;
   final JourneyExit? exit;
   final int sequence;
@@ -105,6 +114,7 @@ class AnalyticsEvent {
       JourneyKind.exchange => 'exchange',
       JourneyKind.payout => 'payout',
       JourneyKind.security => 'security',
+      JourneyKind.destination => 'destination',
       _ => 'auth',
     };
     var stage = step == null ? 'journey' : _snake(step!.name);
@@ -123,6 +133,7 @@ class AnalyticsEvent {
     'terminal': terminal,
     'simulated': simulated,
     if (step != null) 'step': _snake(step!.name),
+    if (resolution != null) 'destination_resolution': resolution!.name,
     if (operation != null) 'operation': operation!,
     if (failure != null) 'failure': _snake(failure!.name),
     if (exit != null) 'exit': _snake(exit!.name),
@@ -210,6 +221,7 @@ class JourneyRecorder {
     JourneyFailure? failure,
     bool terminal = false,
     bool cancelled = false,
+    DestinationResolution? resolution,
   }) {
     final journey = operation._journey;
     if (_disposed || operation._finished || journey.closed) return;
@@ -227,6 +239,7 @@ class JourneyRecorder {
           ? JourneySignal.simulated
           : JourneySignal.succeeded,
       operation: operation,
+      resolution: resolution,
       failure: failure,
       terminal: complete,
       simulated: simulated || (complete && journey.simulated),
@@ -258,6 +271,7 @@ class JourneyRecorder {
     _Journey journey,
     JourneySignal signal, {
     JourneyOperation? operation,
+    DestinationResolution? resolution,
     JourneyFailure? failure,
     JourneyExit? exit,
     bool terminal = false,
@@ -271,6 +285,7 @@ class JourneyRecorder {
       sequence: ++journey.sequence,
       elapsedMs: journey.time.elapsedMilliseconds,
       step: operation?.step,
+      resolution: resolution,
       operation: operation?.number,
       failure: failure,
       exit: exit,

frontend/packages/sxchnge_wallet/README.md

@@ -47,3 +47,17 @@ once on success/failure. Closing the app while pending does not count as draft
 abandonment. No amounts, account IDs or recipient data enter events. All demo
 signals are simulated. Cross-session outcomes require backend event delivery;
 client-only analytics are not production accounting or conversion evidence.
+
+## Saved destinations — #54
+
+The injectable `DestinationService` adds canonical crypto, secure-card capture and
+Russian bank models, saved/one-time input, independent metadata/execution revisions,
+stable created/duplicate outcomes, contextual eligibility and management providers.
+`DummyDestinationService` is customer-scoped and process-local. It has isolated
+fixtures for directory/capture/recovery states, not live banking or card collection.
+The demo wallet binds immutable destination snapshots to quotes and rechecks at its
+synchronous acceptance boundary. Production must enforce those checks atomically
+in the backend. Live mode currently advertises no new destination capabilities and
+preserves explicit selection of the already provisioned wallet method. It never
+uses a demo store. See [the UX/service contract](../../../docs/ux/payout-destinations.md)
+for integration, security, retention, localization and acceptance requirements.

frontend/packages/sxchnge_wallet/lib/src/destinations/bank_paste.dart

@@ -0,0 +1,49 @@
+/// Local, explicit-label paste parsing. Raw pasted text is never retained.
+class BankPaste {
+  BankPaste._(this.values, this.conflicts);
+  final Map<String, String> values;
+  final Set<String> conflicts;
+  static BankPaste parse(String text) {
+    final values = <String, String>{};
+    final conflicts = <String>{};
+    const labels = {
+      'бик': 'bik',
+      'bik': 'bik',
+      'счет': 'account',
+      'счёт': 'account',
+      'номер счета': 'account',
+      'номер счёта': 'account',
+      'account': 'account',
+      'account number': 'account',
+      'имя': 'firstName',
+      'first name': 'firstName',
+      'фамилия': 'lastName',
+      'last name': 'lastName',
+      'отчество': 'patronymic',
+      'patronymic': 'patronymic',
+      'получатель': 'holder',
+      'фио': 'holder',
+      'account holder': 'holder',
+      'банк': 'bank',
+      'bank': 'bank',
+      'корреспондентский счет': 'correspondent',
+      'корреспондентский счёт': 'correspondent',
+      'correspondent account': 'correspondent',
+    };
+    for (final line in text.split(RegExp(r'[\r\n]+'))) {
+      final match = RegExp(r'^\s*([^:=]+)\s*[:=]\s*(.+?)\s*$').firstMatch(line);
+      if (match == null) continue;
+      final key = labels[match[1]!.trim().toLowerCase()];
+      if (key == null) continue;
+      var value = match[2]!.trim();
+      if (['bik', 'account', 'correspondent'].contains(key))
+        value = value.replaceAll(RegExp(r'\s'), '');
+      if (values.containsKey(key) && values[key] != value) conflicts.add(key);
+      values[key] = value;
+    }
+    for (final key in conflicts) {
+      values.remove(key);
+    }
+    return BankPaste._(Map.unmodifiable(values), Set.unmodifiable(conflicts));
+  }
+}

frontend/packages/sxchnge_wallet/lib/src/destinations/dummy.dart

@@ -0,0 +1,614 @@
+import 'dart:convert';
+
+import 'key.dart';
+import 'models.dart';
+import 'service.dart';
+import 'transport.dart';
+
+/// Shared only by injected demo sessions. Never production persistence.
+class DestinationMemory {
+  final records = <String, Map<String, SavedDestination>>{};
+  final attempts = <String, Map<String, (String, CreationResult)>>{};
+  final audit = <DestinationAudit>[];
+  final recoveries = <String, Map<String, (String, String)>>{};
+  final fingerprints = <String, Map<String, String?>>{};
+}
+
+/// Service-authoritative simulation. No raw card capture and no live rails.
+class DummyDestinationService implements DestinationService {
+  DummyDestinationService({
+    this.customer = 'demo-customer',
+    DestinationMemory? memory,
+    DateTime Function()? now,
+  }) : memory = memory ?? DestinationMemory(),
+       now = now ?? DateTime.now;
+  final String customer;
+  final DestinationMemory memory;
+  final DateTime Function() now;
+  final availability = <String, PayoutEligibility>{};
+  int requirementsRevision = 1;
+  bool loseNextSaveResponse = false;
+  bool reusableCards = true, cardRecovery = true;
+  DestinationIssue? nextSaveError;
+  bool directoryUnavailable = false;
+  List<Bank> directory = [
+    const Bank(
+      bik: '044525225',
+      name: 'Demo Bank',
+      city: 'Moscow',
+      correspondent: '30101810400000000225',
+      revision: 'demo-1',
+    ),
+  ];
+  static const assets = [
+    CryptoAsset('demo:ethereum:native', 'ETH', 'eip155:1', 'Ethereum'),
+    CryptoAsset(
+      'demo:ethereum:usdc',
+      'USDC · Ethereum · demo token A',
+      'eip155:1',
+      'Ethereum',
+    ),
+    CryptoAsset(
+      'demo:ethereum:usdc-alt',
+      'USDC · Ethereum · demo token B',
+      'eip155:1',
+      'Ethereum',
+    ),
+    CryptoAsset('demo:polygon:usdc', 'USDC · Polygon', 'eip155:137', 'Polygon'),
+    CryptoAsset(
+      'demo:xrp:native',
+      'XRP',
+      'xrpl:mainnet',
+      'XRP Ledger',
+      memoRequired: true,
+      memoSupported: true,
+    ),
+  ];
+  Map<String, SavedDestination> get _records =>
+      memory.records.putIfAbsent(customer, () => {});
+  Map<String, (String, CreationResult)> get _attempts =>
+      memory.attempts.putIfAbsent(customer, () => {});
+  @override
+  bool get isSimulated => true;
+  @override
+  Future<DestinationCapabilities> capabilities() async =>
+      DestinationCapabilities(
+        types: DestinationType.values,
+        assets: assets,
+        reusableCards: true,
+        cardRecovery: true,
+        simulated: true,
+      );
+  @override
+  Future<List<SavedDestination>> list() async =>
+      _records.values.where((d) => !d.removed).toList();
+  SavedDestination _get(String id) {
+    final d = _records[id];
+    if (d == null) throw const DestinationException(DestinationIssue.removed);
+    return d;
+  }
+
+  @override
+  Future<SavedDestination> get(String id) async => _get(id);
+  void _audit(String reference, String action, String outcome) => memory.audit
+      .add(DestinationAudit(customer, reference, action, outcome, now()));
+  DestinationDetails _validate(DestinationDetails details) {
+    switch (details) {
+      case CryptoDestination d:
+        final asset = assets
+            .where((a) => a.id == d.assetId && a.networkId == d.networkId)
+            .firstOrNull;
+        if (asset == null)
+          throw const DestinationException(
+            DestinationIssue.invalid,
+            field: 'asset',
+          );
+        final address = d.address.trim();
+        final valid = asset.networkId.startsWith('eip155:')
+            ? RegExp(r'^0x[0-9a-fA-F]{40}$').hasMatch(address)
+            : RegExp(r'^r[1-9A-HJ-NP-Za-km-z]{24,34}$').hasMatch(address);
+        if (!valid)
+          throw const DestinationException(
+            DestinationIssue.invalid,
+            field: 'address',
+          );
+        if (asset.memoRequired && !RegExp(r'^\d{1,10}$').hasMatch(d.memo))
+          throw const DestinationException(
+            DestinationIssue.invalid,
+            field: 'memo',
+          );
+        if (!asset.memoSupported && d.memo.isNotEmpty)
+          throw const DestinationException(
+            DestinationIssue.invalid,
+            field: 'memo',
+          );
+        return CryptoDestination(
+          assetId: asset.id,
+          networkId: asset.networkId,
+          address: address,
+          memo: d.memo,
+          assetLabel: asset.label,
+          networkLabel: asset.networkLabel,
+        );
+      case RussianBankDestination d:
+        final account = d.account.replaceAll(RegExp(r'\s'), '');
+        if (d.firstName.trim().isEmpty || d.lastName.trim().isEmpty)
+          throw const DestinationException(
+            DestinationIssue.invalid,
+            field: 'holder',
+          );
+        if (!RegExp(r'^\d{9}$').hasMatch(d.bank.bik) ||
+            !validBankAccount(account, d.bank.bik))
+          throw const DestinationException(
+            DestinationIssue.invalid,
+            field: 'account',
+          );
+        if (directoryUnavailable)
+          throw const DestinationException(
+            DestinationIssue.unavailable,
+            field: 'bank',
+          );
+        final bank = directory.where((b) => b.bik == d.bank.bik).firstOrNull;
+        if (bank == null)
+          throw const DestinationException(
+            DestinationIssue.invalid,
+            field: 'bank',
+          );
+        if (bank.correspondent != d.bank.correspondent)
+          throw const DestinationException(
+            DestinationIssue.bankChanged,
+            field: 'bank',
+          );
+        // Directory display values are authoritative; identity is never guessed.
+        return RussianBankDestination(
+          firstName: d.firstName.trim(),
+          lastName: d.lastName.trim(),
+          patronymic: d.patronymic.trim(),
+          bank: bank,
+          account: account,
+        );
+      case CardDestination d:
+        if (![
+          'demo-card-ready',
+          'demo-card-recover',
+          'demo-card-unknown',
+        ].contains(d.capture))
+          throw const DestinationException(
+            DestinationIssue.invalid,
+            field: 'card',
+          );
+        // These are secure-collection fixtures, not user-entered card metadata.
+        return CardDestination(
+          capture: d.capture,
+          brand: 'Demo card',
+          last4: d.capture == 'demo-card-unknown' ? '0027' : '4242',
+          expiryMonth: 12,
+          expiryYear: now().year + 2,
+        );
+    }
+  }
+
+  @override
+  Future<DestinationValidation> validate(DestinationDetails details) async =>
+      DestinationValidation(DestinationMapper.clone(_validate(details)));
+
+  String? _identity(DestinationDetails details) => switch (details) {
+    CryptoDestination d => jsonEncode([
+      d.type.name,
+      d.assetId,
+      d.networkId,
+      d.networkId.startsWith('eip155:') ? d.address.toLowerCase() : d.address,
+      d.memo,
+    ]),
+    RussianBankDestination d => jsonEncode([
+      d.type.name,
+      d.bank.bik,
+      d.account,
+      d.firstName,
+      d.lastName,
+      d.patronymic,
+    ]),
+    CardDestination d =>
+      d.capture.isEmpty
+          ? (memory.fingerprints[customer] ?? <String, String?>{})[d.identity]
+          : d.capture == 'demo-card-unknown'
+          ? null
+          : 'demo-card-fingerprint:4242',
+  };
+  DestinationDetails _resolve(DestinationInput input) {
+    if (input is OneTimeDestination) return _validate(input.details);
+    final ref = input as SavedReference;
+    final d = _get(ref.id);
+    if (d.removed) throw const DestinationException(DestinationIssue.removed);
+    if (d.executionRevision != ref.executionRevision)
+      throw const DestinationException(DestinationIssue.conflict);
+    return d.details;
+  }
+
+  PayoutEligibility _assess(DestinationInput input, PayoutContext context) {
+    final d = _resolve(input);
+    if (input is SavedReference) {
+      final saved = _get(input.id);
+      if (saved.ownership.actionRequired)
+        return const PayoutEligibility(
+          EligibilityState.requiresAction,
+          reason: DestinationIssue.authorization,
+        );
+      final override = availability[input.id];
+      if (override != null) return override;
+      if (d is CardDestination) {
+        if (d.expiryYear < now().year ||
+            d.expiryYear == now().year && d.expiryMonth < now().month)
+          return const PayoutEligibility(
+            EligibilityState.requiresAction,
+            reason: DestinationIssue.expired,
+          );
+        final ready = saved.bindings.any(
+          (b) =>
+              b.reusable &&
+              b.state == BindingState.ready &&
+              (b.expiresAt == null || now().isBefore(b.expiresAt!)),
+        );
+        if (!ready) {
+          final recoverable =
+              cardRecovery && saved.bindings.any((b) => b.recoverable);
+          final temporary = saved.bindings.any(
+            (b) => b.state == BindingState.unavailable,
+          );
+          return PayoutEligibility(
+            recoverable
+                ? EligibilityState.requiresAction
+                : temporary
+                ? EligibilityState.temporarilyUnavailable
+                : EligibilityState.unsupported,
+            reason: recoverable
+                ? DestinationIssue.authorization
+                : temporary
+                ? DestinationIssue.unavailable
+                : DestinationIssue.unsupported,
+          );
+        }
+      }
+    }
+    if (context.source.isNotEmpty &&
+        !['eur', 'usd', 'gbp'].contains(context.source))
+      return const PayoutEligibility(
+        EligibilityState.unsupported,
+        reason: DestinationIssue.unsupported,
+      );
+    if (d is RussianBankDestination) {
+      if (directoryUnavailable)
+        return const PayoutEligibility(
+          EligibilityState.temporarilyUnavailable,
+          reason: DestinationIssue.unavailable,
+        );
+      final current = directory.where((b) => b.bik == d.bank.bik).firstOrNull;
+      if (current == null || !current.supported)
+        return const PayoutEligibility(
+          EligibilityState.unsupported,
+          reason: DestinationIssue.unsupported,
+        );
+      if (current.correspondent != d.bank.correspondent)
+        return const PayoutEligibility(
+          EligibilityState.requiresAction,
+          reason: DestinationIssue.bankChanged,
+        );
+    }
+    if (d is CardDestination && d.capture == 'demo-card-recover')
+      return const PayoutEligibility(
+        EligibilityState.requiresAction,
+        reason: DestinationIssue.authorization,
+      );
+    return PayoutEligibility(
+      EligibilityState.eligible,
+      canSave: d is! CardDestination || reusableCards || cardRecovery,
+    );
+  }
+
+  @override
+  Future<PayoutEligibility> assess(
+    DestinationInput input,
+    PayoutContext context,
+  ) async => _assess(input, context);
+
+  @override
+  Future<CreationResult> create(
+    DestinationDetails details,
+    String nickname,
+    String idempotencyKey, {
+    String? replaces,
+  }) async {
+    if (idempotencyKey.length < 16 || nickname.length > 80)
+      throw const DestinationException(DestinationIssue.invalid);
+    final payload = jsonEncode([
+      DestinationMapper.details(details).value,
+      nickname,
+      replaces,
+    ]);
+    final previous = _attempts[idempotencyKey];
+    if (previous != null) {
+      if (previous.$1 != payload)
+        throw const DestinationException(DestinationIssue.conflict);
+      return previous.$2;
+    }
+    final error = nextSaveError;
+    nextSaveError = null;
+    if (error != null) {
+      _audit(idempotencyKey, 'create', 'failed');
+      throw DestinationException(error);
+    }
+    if (replaces != null && _get(replaces).removed)
+      throw const DestinationException(DestinationIssue.removed);
+    final normalized = _validate(details);
+    if (normalized is CardDestination && !reusableCards && !cardRecovery)
+      throw const DestinationException(DestinationIssue.unsupported);
+    final identity = _identity(normalized);
+    final existing = identity == null
+        ? null
+        : _records.values
+              .where((r) => !r.removed && _identity(r.details) == identity)
+              .firstOrNull;
+    final result = CreationResult(
+      existing == null ? SaveOutcome.created : SaveOutcome.duplicate,
+      existing?.id ?? destinationKey(),
+    );
+    // Synchronous mutation is the demo's linearization boundary; no await gap.
+    if (existing == null) {
+      _records[result.destinationId] = SavedDestination(
+        id: result.destinationId,
+        details: normalized is CardDestination
+            ? CardDestination(
+                identity: result.destinationId,
+                brand: normalized.brand,
+                last4: normalized.last4,
+                expiryMonth: normalized.expiryMonth,
+                expiryYear: normalized.expiryYear,
+              )
+            : DestinationMapper.clone(normalized),
+        nickname: nickname.trim(),
+        bindings: normalized is CardDestination
+            ? [
+                ProviderBinding(
+                  reference: destinationKey(),
+                  state:
+                      !reusableCards ||
+                          normalized.capture == 'demo-card-recover'
+                      ? BindingState.expired
+                      : BindingState.ready,
+                  reusable: reusableCards,
+                  recoverable: cardRecovery,
+                ),
+              ]
+            : [],
+      );
+    }
+    if (existing == null && normalized is CardDestination)
+      memory.fingerprints.putIfAbsent(
+        customer,
+        () => {},
+      )[result.destinationId] = identity;
+    _attempts[idempotencyKey] = (payload, result);
+    _audit(
+      result.destinationId,
+      replaces == null ? 'create' : 'replacement',
+      result.outcome.name,
+    );
+    if (loseNextSaveResponse) {
+      loseNextSaveResponse = false;
+      throw const DestinationException(DestinationIssue.uncertain);
+    }
+    return result;
+  }
+
+  @override
+  Future<CreationResult?> creation(String idempotencyKey) async =>
+      _attempts[idempotencyKey]?.$2;
+  @override
+  Future<SavedDestination> rename(
+    String id,
+    String nickname,
+    int metadataRevision,
+  ) async {
+    final d = _get(id);
+    if (d.removed) throw const DestinationException(DestinationIssue.removed);
+    if (d.metadataRevision != metadataRevision) {
+      _audit(id, 'rename', 'conflict');
+      throw const DestinationException(DestinationIssue.conflict);
+    }
+    if (nickname.length > 80)
+      throw const DestinationException(
+        DestinationIssue.invalid,
+        field: 'nickname',
+      );
+    final updated = SavedDestination(
+      id: d.id,
+      details: d.details,
+      nickname: nickname.trim(),
+      metadataRevision: d.metadataRevision + 1,
+      executionRevision: d.executionRevision,
+      bindings: d.bindings,
+      lastUsed: d.lastUsed,
+      ownership: d.ownership,
+    );
+    _records[id] = updated;
+    _audit(id, 'rename', 'succeeded');
+    return updated;
+  }
+
+  @override
+  Future<void> remove(
+    String id,
+    int metadataRevision,
+    int executionRevision,
+  ) async {
+    final d = _get(id);
+    if (d.removed) return;
+    if (d.metadataRevision != metadataRevision ||
+        d.executionRevision != executionRevision) {
+      _audit(id, 'remove', 'conflict');
+      throw const DestinationException(DestinationIssue.conflict);
+    }
+    _records[id] = SavedDestination(
+      id: d.id,
+      details: d.details,
+      nickname: d.nickname,
+      metadataRevision: d.metadataRevision + 1,
+      executionRevision: d.executionRevision + 1,
+      removed: true,
+      bindings: d.bindings,
+      lastUsed: d.lastUsed,
+      ownership: d.ownership,
+    );
+    _audit(id, 'remove', 'succeeded');
+  }
+
+  @override
+  Future<List<Bank>> banks(String query, {Future<void>? abortTrigger}) async {
+    if (directoryUnavailable)
+      throw const DestinationException(DestinationIssue.unavailable);
+    final value = query.trim().toLowerCase();
+    if (RegExp(r'^\d+$').hasMatch(value) && value.length > 9)
+      throw const DestinationException(DestinationIssue.invalid, field: 'bik');
+    if (value.length < 2) return [];
+    return directory
+        .where(
+          (b) => value.length == 9 && RegExp(r'^\d+$').hasMatch(value)
+              ? b.bik == value
+              : b.name.toLowerCase().contains(value) || b.bik.contains(value),
+        )
+        .toList();
+  }
+
+  DestinationDetails _snapshot(DestinationDetails details) =>
+      details is CardDestination
+      ? CardDestination(
+          identity: details.identity,
+          brand: details.brand,
+          last4: details.last4,
+          expiryMonth: details.expiryMonth,
+          expiryYear: details.expiryYear,
+        )
+      : DestinationMapper.clone(details);
+
+  @override
+  Future<DestinationLease> prepare(
+    DestinationInput input,
+    PayoutContext context,
+  ) async {
+    final eligibility = _assess(input, context);
+    if (!eligibility.eligible)
+      throw DestinationException(
+        eligibility.reason ?? DestinationIssue.unsupported,
+      );
+    return DestinationLease(
+      input: input,
+      snapshot: _snapshot(_resolve(input)),
+      context: context,
+      requirementsRevision: requirementsRevision,
+      expiresAt: now().add(const Duration(seconds: 60)),
+    );
+  }
+
+  /// Synchronous demo acceptance boundary; production enforcement belongs in BFF.
+  void accept(DestinationLease lease) {
+    if (!now().isBefore(lease.expiresAt))
+      throw const DestinationException(DestinationIssue.expired);
+    if (requirementsRevision != lease.requirementsRevision)
+      throw const DestinationException(DestinationIssue.conflict);
+    final result = _assess(lease.input, lease.context);
+    if (!result.eligible)
+      throw DestinationException(result.reason ?? DestinationIssue.unsupported);
+    if (lease.input case SavedReference ref) {
+      final d = _get(ref.id);
+      _records[d.id] = SavedDestination(
+        id: d.id,
+        details: d.details,
+        nickname: d.nickname,
+        metadataRevision: d.metadataRevision,
+        executionRevision: d.executionRevision,
+        bindings: d.bindings,
+        lastUsed: now(),
+        ownership: d.ownership,
+      );
+    }
+  }
+
+  @override
+  Future<SavedDestination> restoreCard(
+    String id,
+    int executionRevision,
+    CardDestination capture,
+    String idempotencyKey,
+  ) async {
+    if (idempotencyKey.length < 16)
+      throw const DestinationException(DestinationIssue.invalid);
+    final payload = jsonEncode([
+      id,
+      executionRevision,
+      DestinationMapper.details(capture).value,
+    ]);
+    final attempts = memory.recoveries.putIfAbsent(customer, () => {});
+    final previous = attempts[idempotencyKey];
+    if (previous != null) {
+      if (previous.$1 != payload)
+        throw const DestinationException(DestinationIssue.conflict);
+      return _get(previous.$2);
+    }
+    final d = _get(id);
+    if (d.removed) throw const DestinationException(DestinationIssue.removed);
+    if (d.executionRevision != executionRevision)
+      throw const DestinationException(DestinationIssue.conflict);
+    if (!cardRecovery || d.details is! CardDestination)
+      throw const DestinationException(DestinationIssue.unsupported);
+    final normalized = _validate(capture) as CardDestination;
+    final fingerprint = _identity(normalized);
+    if (fingerprint == null || fingerprint != _identity(d.details))
+      throw const DestinationException(DestinationIssue.replacementRequired);
+    if (capture.capture != 'demo-card-ready')
+      throw const DestinationException(DestinationIssue.authorization);
+    final updated = SavedDestination(
+      id: d.id,
+      details: CardDestination(
+        identity: (d.details as CardDestination).identity,
+        brand: normalized.brand,
+        last4: normalized.last4,
+        expiryMonth: normalized.expiryMonth,
+        expiryYear: normalized.expiryYear,
+      ),
+      nickname: d.nickname,
+      metadataRevision: d.metadataRevision,
+      executionRevision: d.executionRevision + 1,
+      lastUsed: d.lastUsed,
+      ownership: d.ownership,
+      bindings: [
+        ProviderBinding(
+          reference: destinationKey(),
+          state: BindingState.ready,
+          reusable: true,
+          recoverable: true,
+        ),
+      ],
+    );
+    _records[id] = updated;
+    attempts[idempotencyKey] = (payload, id);
+    _audit(id, 'bindingRestored', 'succeeded');
+    return updated;
+  }
+
+  @override
+  void clearTransient() {
+    /* No transient server records survive method calls. */
+  }
+}
+
+bool validBankAccount(String account, String bik) {
+  if (!RegExp(r'^\d{20}$').hasMatch(account) ||
+      !RegExp(r'^\d{9}$').hasMatch(bik))
+    return false;
+  final digits = bik.substring(6) + account;
+  var sum = 0;
+  for (var i = 0; i < digits.length; i++) {
+    sum += int.parse(digits[i]) * [7, 1, 3][i % 3];
+  }
+  return sum % 10 == 0;
+}

frontend/packages/sxchnge_wallet/lib/src/destinations/form.dart

@@ -0,0 +1,276 @@
+import 'package:flutter/foundation.dart';
+
+import 'package:sxchnge_analytics/sxchnge_analytics.dart';
+
+import 'key.dart';
+import 'models.dart';
+import 'service.dart';
+
+class DestinationFormProvider extends ChangeNotifier {
+  DestinationFormProvider(
+    this.service,
+    this.analytics, {
+    this.context,
+    this.initial,
+    this.replacing,
+    this.restoring,
+  }) : recorder = JourneyRecorder(analytics),
+       details = initial {
+    if (context == null) _startJourney();
+  }
+  final DestinationService service;
+  final AnalyticsService analytics;
+  final JourneyRecorder recorder;
+  final PayoutContext? context;
+  final DestinationDetails? initial;
+  final String? replacing;
+  final SavedReference? restoring;
+  DestinationDetails? details;
+  String nickname = '';
+  bool save = false, busy = false, _disposed = false, uncertain = false;
+  DestinationIssue? error;
+  String? errorField;
+  CreationResult? saved;
+  PayoutEligibility? eligibility;
+  DestinationInput? result;
+  String? _key;
+  bool _creationStarted = false;
+  bool _journeyStarted = false;
+  void _startJourney() {
+    if (_journeyStarted) return;
+    _journeyStarted = true;
+    final op = recorder.begin(
+      JourneyKind.destination,
+      JourneyStep.destinationDraft,
+      simulated: service.isSimulated,
+    );
+    recorder.finish(op, simulated: service.isSimulated);
+  }
+
+  bool savingFailed = false;
+  bool get hasDraft => details != null || nickname.isNotEmpty;
+  void change(DestinationDetails? value) {
+    if (busy || uncertain) return;
+    details = value;
+    error = null;
+    errorField = null;
+    eligibility = null;
+    result = null;
+    saved = null;
+    _key = null;
+    _creationStarted = false;
+    notifyListeners();
+  }
+
+  void preferences({bool? save, String? nickname}) {
+    if (busy || uncertain) return;
+    if (save == true) _startJourney();
+    if (save == false && this.save) {
+      recorder.abandon(JourneyExit.modeChange);
+      _journeyStarted = false;
+    }
+    this.save = save ?? this.save;
+    this.nickname = nickname ?? this.nickname;
+    _key = null;
+    saved = null;
+    error = null;
+    notifyListeners();
+  }
+
+  Future<void> proceed({bool withoutSaving = false}) async {
+    if (busy || details == null) return;
+    if (withoutSaving && !uncertain) recorder.abandon(JourneyExit.modeChange);
+    if (uncertain && !withoutSaving) {
+      await reconcile();
+      return;
+    }
+    busy = true;
+    error = null;
+    errorField = null;
+    savingFailed = false;
+    if (!uncertain) _creationStarted = false;
+    notifyListeners();
+    try {
+      // Validation precedes both persistence and payout assessment.
+      final normalized = (await service.validate(details!)).details;
+      if (_disposed) return;
+      if (restoring != null) {
+        _key ??= destinationKey();
+        final bindingOperation = recorder.begin(
+          JourneyKind.destination,
+          JourneyStep.destinationBinding,
+          simulated: service.isSimulated,
+        );
+        final restored = await service.restoreCard(
+          restoring!.id,
+          restoring!.executionRevision,
+          normalized as CardDestination,
+          _key!,
+        );
+        recorder.finish(
+          bindingOperation,
+          terminal: true,
+          simulated: service.isSimulated,
+        );
+        if (!_disposed) result = restored.input;
+      } else if (context != null) {
+        eligibility = await service.assess(
+          OneTimeDestination(normalized),
+          context!,
+        );
+        if (_disposed) return;
+      }
+      if (restoring == null &&
+          (context == null || save) &&
+          !withoutSaving &&
+          saved == null) {
+        if (eligibility?.canSave == false)
+          throw const DestinationException(DestinationIssue.unsupported);
+        _key ??= destinationKey();
+        final op = recorder.begin(
+          JourneyKind.destination,
+          JourneyStep.destinationSave,
+          simulated: service.isSimulated,
+        );
+        _creationStarted = true;
+        try {
+          saved = await service.create(
+            normalized,
+            nickname,
+            _key!,
+            replaces: replacing,
+          );
+          _creationStarted = false;
+          if (_disposed) return;
+          recorder.finish(
+            op,
+            simulated: service.isSimulated,
+            terminal: true,
+            resolution: DestinationResolution.values.byName(
+              saved!.outcome.name,
+            ),
+          );
+        } catch (e) {
+          savingFailed = true;
+          recorder.finish(
+            op,
+            failure: JourneyFailure.unavailable,
+            simulated: service.isSimulated,
+          );
+          rethrow;
+        }
+      }
+      if (restoring != null) {
+        // Restored bindings never create or rename a saved destination.
+      } else if (context == null) {
+        if (saved?.outcome == SaveOutcome.created)
+          result = SavedReference(
+            saved!.destinationId,
+            (await service.get(saved!.destinationId)).executionRevision,
+          );
+      } else if (eligibility!.eligible) {
+        if (withoutSaving || saved == null) {
+          result = OneTimeDestination(normalized);
+        } else if (saved!.outcome == SaveOutcome.created) {
+          final d = await service.get(saved!.destinationId);
+          result = d.input;
+        }
+        // Duplicates need explicit Use existing method, never another create.
+      }
+    } on DestinationException catch (e) {
+      error = e.issue;
+      errorField = e.field;
+      uncertain =
+          _creationStarted &&
+          [
+            DestinationIssue.uncertain,
+            DestinationIssue.unavailable,
+          ].contains(e.issue);
+    } catch (_) {
+      error = DestinationIssue.unavailable;
+      uncertain = _creationStarted;
+    }
+    if (_disposed) return;
+    busy = false;
+    notifyListeners();
+  }
+
+  Future<void> useExisting() async {
+    if (busy || saved == null) return;
+    error = null;
+    busy = true;
+    notifyListeners();
+    try {
+      final d = await service.get(saved!.destinationId);
+      if (d.removed) throw const DestinationException(DestinationIssue.removed);
+      if (context != null)
+        eligibility = await service.assess(d.input, context!);
+      if (context == null || eligibility!.eligible) result = d.input;
+    } on DestinationException catch (e) {
+      error = e.issue;
+    } catch (_) {
+      error = DestinationIssue.unavailable;
+    }
+    if (_disposed) return;
+    busy = false;
+    notifyListeners();
+  }
+
+  Future<void> reconcile() async {
+    if (busy || _key == null) return;
+    busy = true;
+    notifyListeners();
+    final op = recorder.begin(
+      JourneyKind.destination,
+      JourneyStep.destinationReconciliation,
+      simulated: service.isSimulated,
+    );
+    try {
+      final outcome = await service.creation(_key!);
+      if (_disposed) return;
+      saved = outcome;
+      recorder.finish(
+        op,
+        simulated: service.isSimulated,
+        terminal: outcome != null,
+        resolution: outcome == null
+            ? null
+            : DestinationResolution.values.byName(outcome.outcome.name),
+      );
+      uncertain = false;
+      _creationStarted = false;
+      error = null;
+      // Absence is an authoritative lookup result, not a timeout inference.
+      if (outcome?.outcome == SaveOutcome.created && context == null) {
+        final d = await service.get(outcome!.destinationId);
+        if (d.removed)
+          throw const DestinationException(DestinationIssue.removed);
+        result = d.input;
+      }
+    } on DestinationException catch (e) {
+      recorder.finish(
+        op,
+        simulated: service.isSimulated,
+        failure: JourneyFailure.unavailable,
+      );
+      error = e.issue;
+    } catch (_) {
+      recorder.finish(
+        op,
+        simulated: service.isSimulated,
+        failure: JourneyFailure.unavailable,
+      );
+      error = DestinationIssue.unavailable;
+    }
+    if (_disposed) return;
+    busy = false;
+    notifyListeners();
+  }
+
+  @override
+  void dispose() {
+    _disposed = true;
+    recorder.dispose(abandonActive: !uncertain);
+    super.dispose();
+  }
+}

frontend/packages/sxchnge_wallet/lib/src/destinations/key.dart

@@ -0,0 +1,7 @@
+import 'dart:math';
+
+/// An opaque attempt/record reference, never derived from destination details.
+String destinationKey() => List.generate(
+  16,
+  (_) => Random.secure().nextInt(256).toRadixString(16).padLeft(2, '0'),
+).join();

frontend/packages/sxchnge_wallet/lib/src/destinations/management.dart

@@ -0,0 +1,53 @@
+import 'package:flutter/foundation.dart';
+
+import 'models.dart';
+import 'service.dart';
+
+class DestinationManagementProvider extends ChangeNotifier {
+  DestinationManagementProvider(this.service, this.destination);
+  final DestinationService service;
+  SavedDestination destination;
+  DestinationIssue? error;
+  bool busy = false, removed = false, _disposed = false;
+  Future<void> rename(String nickname) => _run(() async {
+    destination = await service.rename(
+      destination.id,
+      nickname,
+      destination.metadataRevision,
+    );
+  });
+  Future<void> remove() => _run(() async {
+    await service.remove(
+      destination.id,
+      destination.metadataRevision,
+      destination.executionRevision,
+    );
+    removed = true;
+  });
+  Future<void> refresh() => _run(() async {
+    destination = await service.get(destination.id);
+    removed = destination.removed;
+  });
+  Future<void> _run(Future<void> Function() action) async {
+    if (busy) return;
+    busy = true;
+    error = null;
+    notifyListeners();
+    try {
+      await action();
+    } on DestinationException catch (e) {
+      error = e.issue;
+    } catch (_) {
+      error = DestinationIssue.unavailable;
+    }
+    if (_disposed) return;
+    busy = false;
+    notifyListeners();
+  }
+
+  @override
+  void dispose() {
+    _disposed = true;
+    super.dispose();
+  }
+}

frontend/packages/sxchnge_wallet/lib/src/destinations/models.dart

@@ -0,0 +1,255 @@
+enum DestinationType { crypto, card, russianBank }
+
+enum EligibilityState {
+  eligible,
+  temporarilyUnavailable,
+  requiresAction,
+  unsupported,
+}
+
+enum DestinationIssue {
+  invalid,
+  unavailable,
+  uncertain,
+  conflict,
+  removed,
+  expired,
+  bankChanged,
+  authorization,
+  unsupported,
+  duplicate,
+  replacementRequired,
+}
+
+enum SaveOutcome { created, duplicate }
+
+enum BindingState { ready, expired, revoked, unavailable }
+
+class DestinationException implements Exception {
+  const DestinationException(this.issue, {this.field});
+  final DestinationIssue issue;
+  final String? field;
+}
+
+sealed class DestinationDetails {
+  const DestinationDetails();
+  DestinationType get type;
+  String get display;
+  String get review;
+}
+
+class CryptoDestination extends DestinationDetails {
+  const CryptoDestination({
+    required this.assetId,
+    required this.networkId,
+    required this.address,
+    this.memo = '',
+    required this.assetLabel,
+    required this.networkLabel,
+  });
+  final String assetId, networkId, address, memo, assetLabel, networkLabel;
+  @override
+  DestinationType get type => DestinationType.crypto;
+  @override
+  String get display =>
+      '$assetLabel · $networkLabel · ${address.length > 14 ? '${address.substring(0, 6)}…${address.substring(address.length - 6)}' : address}';
+  @override
+  String get review =>
+      '$assetLabel · $networkLabel\n$address${memo.isEmpty ? '' : '\n$memo'}';
+}
+
+/// Secure capture references are short lived, not PAN/CVV or destination IDs.
+class CardDestination extends DestinationDetails {
+  const CardDestination({
+    this.capture = '',
+    this.identity = '',
+    required this.brand,
+    required this.last4,
+    required this.expiryMonth,
+    required this.expiryYear,
+  });
+  final String capture, identity, brand, last4;
+  final int expiryMonth, expiryYear;
+  @override
+  DestinationType get type => DestinationType.card;
+  @override
+  String get display => '$brand · •••• $last4';
+  @override
+  String get review => display;
+}
+
+class RussianBankDestination extends DestinationDetails {
+  const RussianBankDestination({
+    required this.firstName,
+    required this.lastName,
+    this.patronymic = '',
+    required this.bank,
+    required this.account,
+  });
+  final String firstName, lastName, patronymic, account;
+  final Bank bank;
+  String get holder =>
+      [firstName, lastName, patronymic].where((s) => s.isNotEmpty).join(' ');
+  @override
+  DestinationType get type => DestinationType.russianBank;
+  @override
+  String get display =>
+      '${bank.name} · •••• ${account.length < 4 ? account : account.substring(account.length - 4)}';
+  @override
+  String get review =>
+      '$holder\n${bank.name}\n${bank.bik}\n$account\n${bank.correspondent}';
+}
+
+class Bank {
+  const Bank({
+    required this.bik,
+    required this.name,
+    required this.city,
+    required this.correspondent,
+    required this.revision,
+    this.supported = true,
+  });
+  final String bik, name, city, correspondent, revision;
+  final bool supported;
+}
+
+class CryptoAsset {
+  const CryptoAsset(
+    this.id,
+    this.label,
+    this.networkId,
+    this.networkLabel, {
+    this.memoRequired = false,
+    this.memoSupported = false,
+  });
+  final String id, label, networkId, networkLabel;
+  final bool memoRequired, memoSupported;
+}
+
+class ProviderBinding {
+  const ProviderBinding({
+    required this.reference,
+    required this.state,
+    required this.reusable,
+    this.recoverable = false,
+    this.expiresAt,
+  });
+  final String reference;
+  final BindingState state;
+  final bool reusable, recoverable;
+  final DateTime? expiresAt;
+}
+
+class OwnershipAssessment {
+  const OwnershipAssessment({
+    this.declaredOwn = true,
+    this.verified = false,
+    this.actionRequired = false,
+  });
+  final bool declaredOwn, verified, actionRequired;
+}
+
+class SavedDestination {
+  SavedDestination({
+    required this.id,
+    required this.details,
+    this.nickname = '',
+    this.metadataRevision = 1,
+    this.executionRevision = 1,
+    this.removed = false,
+    this.lastUsed,
+    this.ownership = const OwnershipAssessment(),
+    List<ProviderBinding> bindings = const [],
+  }) : bindings = List.unmodifiable(bindings);
+  final String id, nickname;
+  final DestinationDetails details;
+  final int metadataRevision, executionRevision;
+  final bool removed;
+  final DateTime? lastUsed;
+  final OwnershipAssessment ownership;
+  final List<ProviderBinding> bindings;
+  String get label => nickname.isEmpty ? details.display : nickname;
+  SavedReference get input => SavedReference(id, executionRevision);
+}
+
+sealed class DestinationInput {
+  const DestinationInput();
+}
+
+class SavedReference extends DestinationInput {
+  const SavedReference(this.id, this.executionRevision);
+  final String id;
+  final int executionRevision;
+}
+
+class OneTimeDestination extends DestinationInput {
+  const OneTimeDestination(this.details);
+  final DestinationDetails details;
+}
+
+class PayoutContext {
+  const PayoutContext(this.source, {this.amount});
+  final String source;
+  final int? amount;
+}
+
+class PayoutEligibility {
+  const PayoutEligibility(this.state, {this.reason, this.canSave = true});
+  final EligibilityState state;
+  final DestinationIssue? reason;
+  final bool canSave;
+  bool get eligible => state == EligibilityState.eligible;
+}
+
+class DestinationValidation {
+  const DestinationValidation(this.details);
+  final DestinationDetails details;
+}
+
+class DestinationCapabilities {
+  DestinationCapabilities({
+    List<DestinationType> types = const [],
+    List<CryptoAsset> assets = const [],
+    this.reusableCards = false,
+    this.cardRecovery = false,
+    this.simulated = false,
+  }) : types = List.unmodifiable(types),
+       assets = List.unmodifiable(assets);
+  final List<DestinationType> types;
+  final List<CryptoAsset> assets;
+  final bool reusableCards, cardRecovery, simulated;
+}
+
+/// Outcome identity never changes when a record is later renamed or removed.
+class CreationResult {
+  const CreationResult(this.outcome, this.destinationId);
+  final SaveOutcome outcome;
+  final String destinationId;
+}
+
+class DestinationLease {
+  const DestinationLease({
+    required this.input,
+    required this.snapshot,
+    required this.context,
+    required this.requirementsRevision,
+    required this.expiresAt,
+  });
+  final DestinationInput input;
+  final DestinationDetails snapshot;
+  final PayoutContext context;
+  final int requirementsRevision;
+  final DateTime expiresAt;
+}
+
+class DestinationAudit {
+  const DestinationAudit(
+    this.actor,
+    this.reference,
+    this.action,
+    this.outcome,
+    this.at,
+  );
+  final String actor, reference, action, outcome;
+  final DateTime at;
+}

frontend/packages/sxchnge_wallet/lib/src/destinations/provider.dart

@@ -0,0 +1,65 @@
+import 'package:flutter/foundation.dart';
+
+import 'models.dart';
+import 'service.dart';
+
+class DestinationsProvider extends ChangeNotifier {
+  DestinationsProvider(this.service);
+  final DestinationService service;
+  DestinationCapabilities? capabilities;
+  List<SavedDestination> methods = [];
+  bool loading = false, failed = false, _disposed = false;
+  int _revision = 0;
+  Future<void> refresh() async {
+    final revision = ++_revision;
+    loading = true;
+    failed = false;
+    notifyListeners();
+    try {
+      final caps = await service.capabilities();
+      final rows = await service.list();
+      if (_disposed || revision != _revision) return;
+      capabilities = caps;
+      methods = rows;
+    } catch (_) {
+      if (_disposed || revision != _revision) return;
+      failed = true;
+    }
+    if (_disposed) return;
+    loading = false;
+    notifyListeners();
+  }
+
+  List<SavedDestination> search(String query, DestinationType type) {
+    final q = query.trim().toLowerCase();
+    final rows = methods
+        .where(
+          (d) =>
+              d.details.type == type &&
+              '${d.label} ${d.details.display}'.toLowerCase().contains(q),
+        )
+        .toList();
+    rows.sort(
+      (a, b) => (b.lastUsed ?? DateTime(1970)).compareTo(
+        a.lastUsed ?? DateTime(1970),
+      ),
+    );
+    return rows;
+  }
+
+  void reset() {
+    _revision++;
+    methods = [];
+    capabilities = null;
+    loading = failed = false;
+    service.clearTransient();
+    notifyListeners();
+  }
+
+  @override
+  void dispose() {
+    _disposed = true;
+    _revision++;
+    super.dispose();
+  }
+}

frontend/packages/sxchnge_wallet/lib/src/destinations/search.dart

@@ -0,0 +1,65 @@
+import 'dart:async';
+
+import 'package:flutter/foundation.dart';
+
+import 'models.dart';
+import 'service.dart';
+
+class BankSearchProvider extends ChangeNotifier {
+  BankSearchProvider(this.service);
+  final DestinationService service;
+  Timer? _timer;
+  Completer<void>? _abort;
+  int _generation = 0;
+  bool _disposed = false, loading = false;
+  String query = '';
+  List<Bank> results = [];
+  DestinationIssue? error;
+  void search(String value) {
+    _timer?.cancel();
+    if (_abort != null && !_abort!.isCompleted) _abort!.complete();
+    _abort = null;
+    final generation = ++_generation;
+    query = value;
+    results = [];
+    error = null;
+    loading = false;
+    if (value.trim().length >= 2) {
+      _timer = Timer(
+        const Duration(milliseconds: 350),
+        () => _lookup(value, generation),
+      );
+    }
+    notifyListeners();
+  }
+
+  Future<void> _lookup(String value, int generation) async {
+    loading = true;
+    notifyListeners();
+    try {
+      final abort = Completer<void>();
+      _abort = abort;
+      final rows = await service.banks(value, abortTrigger: abort.future);
+      if (_disposed || generation != _generation) return;
+      results = rows;
+      if (rows.isEmpty) error = DestinationIssue.invalid;
+    } on DestinationException catch (e) {
+      if (!_disposed && generation == _generation) error = e.issue;
+    } catch (_) {
+      if (!_disposed && generation == _generation)
+        error = DestinationIssue.unavailable;
+    }
+    if (_disposed || generation != _generation) return;
+    loading = false;
+    notifyListeners();
+  }
+
+  @override
+  void dispose() {
+    _disposed = true;
+    _generation++;
+    _timer?.cancel();
+    if (_abort != null && !_abort!.isCompleted) _abort!.complete();
+    super.dispose();
+  }
+}

frontend/packages/sxchnge_wallet/lib/src/destinations/selection.dart

@@ -0,0 +1,64 @@
+import 'package:flutter/foundation.dart';
+
+import 'models.dart';
+import 'service.dart';
+
+class DestinationSelectionProvider extends ChangeNotifier {
+  DestinationSelectionProvider(this.service, this.context);
+  final DestinationService service;
+  final PayoutContext context;
+  final assessments = <String, PayoutEligibility>{};
+  bool busy = false, _disposed = false;
+  DestinationIssue? error;
+  Future<void> assess(List<SavedDestination> methods) async {
+    for (final d in methods) {
+      try {
+        final assessment = await service.assess(d.input, context);
+        if (_disposed) return;
+        assessments[d.id] = assessment;
+      } on DestinationException catch (e) {
+        if (_disposed) return;
+        assessments[d.id] = PayoutEligibility(
+          EligibilityState.requiresAction,
+          reason: e.issue,
+        );
+      } catch (_) {
+        if (_disposed) return;
+        assessments[d.id] = const PayoutEligibility(
+          EligibilityState.temporarilyUnavailable,
+          reason: DestinationIssue.unavailable,
+        );
+      }
+    }
+    if (!_disposed) notifyListeners();
+  }
+
+  Future<SavedReference?> select(SavedDestination d) async {
+    if (busy) return null;
+    busy = true;
+    error = null;
+    notifyListeners();
+    SavedReference? result;
+    try {
+      final current = await service.get(d.id);
+      final a = await service.assess(current.input, context);
+      if (_disposed) return null;
+      assessments[d.id] = a;
+      if (a.eligible) result = current.input;
+    } on DestinationException catch (e) {
+      error = e.issue;
+    } catch (_) {
+      error = DestinationIssue.unavailable;
+    }
+    if (_disposed) return null;
+    busy = false;
+    notifyListeners();
+    return result;
+  }
+
+  @override
+  void dispose() {
+    _disposed = true;
+    super.dispose();
+  }
+}

frontend/packages/sxchnge_wallet/lib/src/destinations/service.dart

@@ -0,0 +1,39 @@
+import 'models.dart';
+
+abstract interface class DestinationService {
+  bool get isSimulated;
+  Future<DestinationCapabilities> capabilities();
+  Future<List<SavedDestination>> list();
+  Future<SavedDestination> get(String id);
+  Future<DestinationValidation> validate(DestinationDetails details);
+  Future<PayoutEligibility> assess(
+    DestinationInput input,
+    PayoutContext context,
+  );
+  Future<CreationResult> create(
+    DestinationDetails details,
+    String nickname,
+    String idempotencyKey, {
+    String? replaces,
+  });
+  Future<CreationResult?> creation(String idempotencyKey);
+  Future<SavedDestination> rename(
+    String id,
+    String nickname,
+    int metadataRevision,
+  );
+  Future<void> remove(String id, int metadataRevision, int executionRevision);
+  Future<List<Bank>> banks(String query, {Future<void>? abortTrigger});
+  Future<DestinationLease> prepare(
+    DestinationInput input,
+    PayoutContext context,
+  );
+
+  Future<SavedDestination> restoreCard(
+    String id,
+    int executionRevision,
+    CardDestination capture,
+    String idempotencyKey,
+  );
+  void clearTransient();
+}

frontend/packages/sxchnge_wallet/lib/src/destinations/transport.dart

@@ -0,0 +1,116 @@
+import 'models.dart';
+
+/// Local DTO boundary: transport fields never escape services into providers/UI.
+class DestinationDTO {
+  const DestinationDTO(this.value);
+  final Map<String, Object?> value;
+}
+
+abstract final class DestinationMapper {
+  static DestinationDTO details(DestinationDetails value) =>
+      DestinationDTO(switch (value) {
+        CryptoDestination d => {
+          'type': 'crypto',
+          'assetId': d.assetId,
+          'networkId': d.networkId,
+          'address': d.address,
+          'memo': d.memo,
+          'assetLabel': d.assetLabel,
+          'networkLabel': d.networkLabel,
+        },
+        CardDestination d => {
+          'type': 'card',
+          'capture': d.capture,
+          'identity': d.identity,
+          'brand': d.brand,
+          'last4': d.last4,
+          'expiryMonth': d.expiryMonth,
+          'expiryYear': d.expiryYear,
+        },
+        RussianBankDestination d => {
+          'type': 'russianBank',
+          'firstName': d.firstName,
+          'lastName': d.lastName,
+          'patronymic': d.patronymic,
+          'account': d.account,
+          'bank': bank(d.bank),
+        },
+      });
+  static Map<String, Object?> bank(Bank b) => {
+    'bik': b.bik,
+    'name': b.name,
+    'city': b.city,
+    'correspondent': b.correspondent,
+    'revision': b.revision,
+    'supported': b.supported,
+  };
+  static Bank fromBank(Map<String, dynamic> v) => Bank(
+    bik: v['bik'] as String,
+    name: v['name'] as String,
+    city: v['city'] as String,
+    correspondent: v['correspondent'] as String,
+    revision: v['revision'] as String,
+    supported: v['supported'] as bool,
+  );
+  static DestinationDetails fromDTO(DestinationDTO dto) {
+    final d = dto.value;
+    return switch (d['type']) {
+      'crypto' => CryptoDestination(
+        assetId: d['assetId'] as String,
+        networkId: d['networkId'] as String,
+        address: d['address'] as String,
+        memo: d['memo'] as String,
+        assetLabel: d['assetLabel'] as String,
+        networkLabel: d['networkLabel'] as String,
+      ),
+      'card' => CardDestination(
+        capture: d['capture'] as String,
+        identity: d['identity'] as String,
+        brand: d['brand'] as String,
+        last4: d['last4'] as String,
+        expiryMonth: d['expiryMonth'] as int,
+        expiryYear: d['expiryYear'] as int,
+      ),
+      'russianBank' => RussianBankDestination(
+        firstName: d['firstName'] as String,
+        lastName: d['lastName'] as String,
+        patronymic: d['patronymic'] as String,
+        account: d['account'] as String,
+        bank: fromBank(Map<String, dynamic>.from(d['bank'] as Map)),
+      ),
+      _ => throw const DestinationException(DestinationIssue.unsupported),
+    };
+  }
+
+  static DestinationDetails clone(DestinationDetails d) => fromDTO(details(d));
+}
+
+sealed class DestinationInputDTO {
+  const DestinationInputDTO();
+}
+
+class SavedInputDTO extends DestinationInputDTO {
+  const SavedInputDTO(this.id, this.executionRevision);
+  final String id;
+  final int executionRevision;
+}
+
+class OneTimeInputDTO extends DestinationInputDTO {
+  const OneTimeInputDTO(this.details);
+  final DestinationDTO details;
+}
+
+abstract final class DestinationInputMapper {
+  static DestinationInputDTO toDTO(DestinationInput input) => switch (input) {
+    SavedReference r => SavedInputDTO(r.id, r.executionRevision),
+    OneTimeDestination d => OneTimeInputDTO(
+      DestinationMapper.details(d.details),
+    ),
+  };
+  static DestinationInput fromDTO(DestinationInputDTO dto) => switch (dto) {
+    SavedInputDTO d => SavedReference(d.id, d.executionRevision),
+    OneTimeInputDTO d => OneTimeDestination(
+      DestinationMapper.fromDTO(d.details),
+    ),
+  };
+}

frontend/packages/sxchnge_wallet/lib/src/destinations/unavailable.dart

@@ -0,0 +1,70 @@
+import 'models.dart';
+import 'service.dart';
+
+/// Fail closed when the live backend has not supplied the destination contract.
+/// Never substitutes a demo store for an authenticated live wallet.
+class UnavailableDestinationService implements DestinationService {
+  const UnavailableDestinationService();
+  @override
+  bool get isSimulated => false;
+  @override
+  Future<DestinationCapabilities> capabilities() async =>
+      DestinationCapabilities();
+  @override
+  Future<List<SavedDestination>> list() async => [];
+  Never _unsupported() =>
+      throw const DestinationException(DestinationIssue.unsupported);
+  @override
+  Future<SavedDestination> get(String id) async => _unsupported();
+  @override
+  Future<DestinationValidation> validate(DestinationDetails details) async =>
+      _unsupported();
+  @override
+  Future<PayoutEligibility> assess(
+    DestinationInput input,
+    PayoutContext context,
+  ) async => const PayoutEligibility(
+    EligibilityState.unsupported,
+    reason: DestinationIssue.unsupported,
+    canSave: false,
+  );
+  @override
+  Future<CreationResult> create(
+    DestinationDetails details,
+    String nickname,
+    String idempotencyKey, {
+    String? replaces,
+  }) async => _unsupported();
+  @override
+  Future<CreationResult?> creation(String idempotencyKey) async =>
+      _unsupported();
+  @override
+  Future<SavedDestination> rename(
+    String id,
+    String nickname,
+    int metadataRevision,
+  ) async => _unsupported();
+  @override
+  Future<void> remove(
+    String id,
+    int metadataRevision,
+    int executionRevision,
+  ) async => _unsupported();
+  @override
+  Future<List<Bank>> banks(String query, {Future<void>? abortTrigger}) async =>
+      _unsupported();
+  @override
+  Future<DestinationLease> prepare(
+    DestinationInput input,
+    PayoutContext context,
+  ) async => _unsupported();
+  @override
+  Future<SavedDestination> restoreCard(
+    String id,
+    int executionRevision,
+    CardDestination capture,
+    String idempotencyKey,
+  ) async => _unsupported();
+  @override
+  void clearTransient() {}
+}

frontend/packages/sxchnge_wallet/lib/src/models/wallet.dart

@@ -1,3 +1,5 @@
+import '../destinations/models.dart';
+
 enum TransferKind { topUp, exchange, payout }
 
 enum OperationStatus { pending, completed, failed }
@@ -12,6 +14,7 @@ enum WalletError {
   unsupported,
   notFound,
   uncertain,
+  destinationChanged,
 }
 
 class WalletException implements Exception {
@@ -64,12 +67,14 @@ class TransferRequest {
     required this.amount,
     this.destination,
     this.recipient = '',
+    this.payoutDestination,
   });
   final TransferKind kind;
   final String source;
   final int amount;
   final String? destination;
   final String recipient;
+  final DestinationInput? payoutDestination;
 }
 
 class Quote {
@@ -82,11 +87,15 @@ class Quote {
     required this.expiresAt,
     required this.rateNumerator,
     required this.rateDenominator,
+    this.payoutSnapshot,
+    this.payoutTerms,
   });
   final String id;
   final TransferRequest request;
   final int fee, debit, credit, rateNumerator, rateDenominator;
   final DateTime expiresAt;
+  final DestinationDetails? payoutSnapshot;
+  final PayoutTerms? payoutTerms;
 }
 
 class WalletOperation {
@@ -116,3 +125,14 @@ class AccountProfile {
   const AccountProfile(this.locale);
   final String locale;
 }
+
+class PayoutTerms {
+  const PayoutTerms(
+    this.amount,
+    this.precision,
+    this.assetLabel,
+    this.expectedSeconds,
+  );
+  final int amount, precision, expectedSeconds;
+  final String assetLabel;
+}

frontend/packages/sxchnge_wallet/lib/src/providers/transfer.dart

@@ -6,6 +6,7 @@ import 'package:sxchnge_analytics/sxchnge_analytics.dart';
 
 import 'package:sxchnge_auth/sxchnge_auth.dart';
 
+import '../destinations/models.dart';
 import '../models/wallet.dart';
 import 'wallet.dart';
 
@@ -40,16 +41,18 @@ class TransferProvider extends ChangeNotifier {
     if (!accounts.any((a) => a.id == destination) || destination == source) {
       destination = accounts.where((a) => a.id != source).firstOrNull?.id;
     }
-    if (!wallet.service.isSimulated && kind == TransferKind.payout) {
-      recipient = wallet.account(source)?.payoutMethod ?? '';
-    }
   }
 
   void _walletChanged() {
     if (_disposed) return;
     final previous = source;
     _syncAccounts();
-    if (source != previous) notifyListeners();
+    if (source != previous) {
+      payoutDestination = null;
+      payoutLabel = '';
+      recipient = '';
+      notifyListeners();
+    }
   }
 
   final WalletProvider wallet;
@@ -58,6 +61,8 @@ class TransferProvider extends ChangeNotifier {
   String source;
   String? destination;
   String amount = '', recipient = '';
+  DestinationInput? payoutDestination;
+  String payoutLabel = '';
   Quote? quote;
   WalletOperation? result;
   WalletError? error;
@@ -72,7 +77,7 @@ class TransferProvider extends ChangeNotifier {
     TransferKind.payout => JourneyKind.payout,
   };
   bool get hasDraft =>
-      amount.isNotEmpty || (wallet.service.isSimulated && recipient.isNotEmpty);
+      amount.isNotEmpty || payoutDestination != null || recipient.isNotEmpty;
   bool get expired =>
       quote != null && !DateTime.now().isBefore(quote!.expiresAt);
   void change({
@@ -80,8 +85,17 @@ class TransferProvider extends ChangeNotifier {
     String? destination,
     String? amount,
     String? recipient,
+    DestinationInput? payoutDestination,
+    String? payoutLabel,
   }) {
     if (busy || uncertain) return;
+    if (source != null && source != this.source) {
+      this.payoutDestination = null;
+      this.payoutLabel = '';
+      recipient = '';
+    }
+    this.payoutDestination = payoutDestination ?? this.payoutDestination;
+    this.payoutLabel = payoutLabel ?? this.payoutLabel;
     this.source = source ?? this.source;
     this.destination = destination ?? this.destination;
     this.amount = amount ?? this.amount;
@@ -96,6 +110,36 @@ class TransferProvider extends ChangeNotifier {
     notifyListeners();
   }
 
+  Future<void> selectPayout(DestinationInput input) async {
+    if (busy || uncertain || wallet.destinations == null) return;
+    busy = true;
+    error = null;
+    notifyListeners();
+    try {
+      final service = wallet.destinations!;
+      final assessment = await service.assess(
+        input,
+        PayoutContext(source, amount: wallet.account(source)?.parse(amount)),
+      );
+      if (!assessment.eligible)
+        throw const DestinationException(DestinationIssue.unsupported);
+      final details = input is OneTimeDestination
+          ? input.details
+          : (await service.get((input as SavedReference).id)).details;
+      if (_disposed) return;
+      busy = false;
+      change(payoutDestination: input, payoutLabel: details.display);
+    } catch (_) {
+      if (_disposed) return;
+      payoutDestination = null;
+      payoutLabel = '';
+      error = WalletError.destinationChanged;
+    }
+    if (_disposed) return;
+    busy = false;
+    notifyListeners();
+  }
+
   void edit() {
     if (!busy && !uncertain) {
       quote = null;
@@ -133,6 +177,7 @@ class TransferProvider extends ChangeNotifier {
           amount: money,
           destination: kind == TransferKind.exchange ? destination : null,
           recipient: recipient.trim(),
+          payoutDestination: payoutDestination,
         ),
       );
       if (_disposed || revision != _revision) return;
@@ -142,6 +187,10 @@ class TransferProvider extends ChangeNotifier {
     } catch (e) {
       if (_disposed) return;
       error = _code(e);
+      if (error == WalletError.destinationChanged) {
+        payoutDestination = null;
+        payoutLabel = '';
+      }
       recorder.finish(op, failure: _failure(error!));
     }
     if (_disposed) return;
@@ -225,6 +274,11 @@ class TransferProvider extends ChangeNotifier {
         uncertain = false;
       } else {
         error = _code(e);
+        if (error == WalletError.destinationChanged) {
+          quote = null;
+          payoutDestination = null;
+          payoutLabel = '';
+        }
       }
       // All transport/unexpected failures are ambiguous after execution started.
       uncertain = [
@@ -247,6 +301,7 @@ class TransferProvider extends ChangeNotifier {
     error = null;
     factorError = null;
     recipient = '';
+    payoutDestination = null;
     recorder.finish(op, simulated: wallet.service.isSimulated);
     wallet.track(value, recorder, journey);
     _handedOff = true;

frontend/packages/sxchnge_wallet/lib/src/providers/wallet.dart

@@ -6,12 +6,19 @@ import 'package:sxchnge_analytics/sxchnge_analytics.dart';
 
 import 'package:sxchnge_auth/sxchnge_auth.dart';
 
+import '../destinations/service.dart';
 import '../models/wallet.dart';
 import '../services/contracts.dart';
 
 class WalletProvider extends ChangeNotifier {
-  WalletProvider(this.service, this.analytics, {this.factors});
+  WalletProvider(
+    this.service,
+    this.analytics, {
+    this.factors,
+    this.destinations,
+  });
   final WalletService service;
+  final DestinationService? destinations;
   final TwoFactorService? factors;
   final AnalyticsService analytics;
   WalletSnapshot? data;

frontend/packages/sxchnge_wallet/lib/src/services/backend.dart

@@ -94,10 +94,15 @@ class BackendWalletService implements WalletService {
   @override
   Future<WalletSnapshot> fetch() => _mapped(send(''), BackendMapper.snapshot);
   @override
-  Future<Quote> quote(TransferRequest request) => _mapped(
+  Future<Quote> quote(TransferRequest request) async {
+    if (request.payoutDestination != null)
+      throw const WalletException(WalletError.unsupported);
+    return _mapped(
       send('/quote', body: BackendMapper.request(request)),
       BackendMapper.quote,
     );
+  }
+
   @override
   Future<WalletOperation> submit(
     String quoteId,

frontend/packages/sxchnge_wallet/lib/src/services/dummy.dart

@@ -5,6 +5,9 @@ import 'package:sxchnge_auth/sxchnge_auth.dart';
 import 'package:sxchnge_kyc/limits_transport.dart';
 import 'package:sxchnge_kyc/sxchnge_kyc.dart';
 
+import '../destinations/dummy.dart';
+import '../destinations/models.dart';
+import '../destinations/transport.dart';
 import '../models/wallet.dart';
 import '../transport/wallet.dart';
 import 'contracts.dart';
@@ -14,13 +17,17 @@ class DummyWalletService implements WalletService {
   DummyWalletService(
     this.identity, {
     this.factors,
+    DummyDestinationService? destinations,
     this.delay = const Duration(milliseconds: 350),
     this.settlement = const Duration(seconds: 2),
     DateTime Function()? now,
     String initialLocale = 'en',
-  }) : now = now ?? DateTime.now,
+  }) : destinations = destinations ?? DummyDestinationService(now: now),
+       now = now ?? DateTime.now,
        _locale = initialLocale;
   final IdentityService identity;
+  final DummyDestinationService destinations;
+  final _destinationLeases = <String, DestinationLease>{};
   final TwoFactorService? factors;
   final Duration delay, settlement;
   final DateTime Function() now;
@@ -59,6 +66,10 @@ class DummyWalletService implements WalletService {
   };
   int _eur(int minor, String id) => (minor * _weight(id) + 1099) ~/ 1100;
   void _settle() {
+    _quotes.removeWhere((_, quote) => !now().isBefore(quote.expires));
+    _destinationLeases.removeWhere(
+      (_, lease) => !now().isBefore(lease.expiresAt),
+    );
     for (final o in _submissions.values) {
       if (o.status != 'pending' || now().isBefore(o.ready)) continue;
       o.status = o.fail ? 'failed' : 'completed';
@@ -133,9 +144,19 @@ class DummyWalletService implements WalletService {
     if (r.kind == TransferKind.exchange &&
         (r.source == r.destination || r.destination == null))
       throw const WalletException(WalletError.unsupported);
-    if (r.kind == TransferKind.payout &&
+    DestinationLease? lease;
-        (r.recipient.trim().length < 6 || r.recipient.length > 140))
+    if (r.kind == TransferKind.payout) {
+      if (r.payoutDestination == null)
         throw const WalletException(WalletError.invalidRecipient);
+      try {
+        lease = await destinations.prepare(
+          r.payoutDestination!,
+          PayoutContext(r.source, amount: r.amount),
+        );
+      } on DestinationException {
+        throw const WalletException(WalletError.destinationChanged);
+      }
+    }
     if (r.kind == TransferKind.exchange) _account(r.destination!);
     final fee = switch (r.kind) {
       TransferKind.topUp => 0,
@@ -146,19 +167,30 @@ class DummyWalletService implements WalletService {
     final d = r.kind == TransferKind.exchange ? _weight(r.destination!) : 1;
     final q = QuoteDTO(
       'quote-${++_serial}',
-      WalletMapper.request(r),
+      WalletMapper.request(r, includePayoutInput: false),
       fee,
       r.kind == TransferKind.topUp ? r.amount : r.amount + fee,
       r.amount * n ~/ d,
       now().add(const Duration(seconds: 60)),
       n,
       d,
+      payoutTerms: lease == null
+          ? null
+          : PayoutTermsDTO(r.amount, 2, switch (lease.snapshot) {
+              CryptoDestination d => d.assetLabel,
+              RussianBankDestination() => 'RUB',
+              CardDestination() => _account(r.source).currency,
+            }, settlement.inSeconds),
+      payoutSnapshot: lease == null
+          ? null
+          : DestinationMapper.details(lease.snapshot),
     );
     if (q.credit <= 0) throw const WalletException(WalletError.invalidAmount);
     final verified = await _verified();
     _settle();
     _check(q, verified);
     _quotes[q.id] = q;
+    if (lease != null) _destinationLeases[q.id] = lease;
     return WalletMapper.quote(q);
   }
 
@@ -193,6 +225,17 @@ class DummyWalletService implements WalletService {
     if (_usedQuotes.contains(q.id))
       throw const WalletException(WalletError.expiredQuote);
     _check(q, verified);
+    final lease = _destinationLeases[q.id];
+    if (q.request.kind == 'payout' && lease == null)
+      throw const WalletException(WalletError.expiredQuote);
+    if (lease != null) {
+      try {
+        destinations.accept(lease);
+      } on DestinationException {
+        throw const WalletException(WalletError.destinationChanged);
+      }
+    }
+    // No asynchronous gap between destination acceptance and financial mutation.
     _usedQuotes.add(q.id);
     if (q.request.kind != 'topUp')
       _account(q.request.source).available -= q.debit;
@@ -205,6 +248,7 @@ class DummyWalletService implements WalletService {
     );
     failNextOperation = false;
     _submissions[idempotencyKey] = o;
+    _destinationLeases.remove(q.id);
     if (loseNextResponse) {
       loseNextResponse = false;
       throw const WalletException(WalletError.uncertain);

frontend/packages/sxchnge_wallet/lib/src/transport/wallet.dart

@@ -1,3 +1,4 @@
+import '../destinations/transport.dart';
 import '../models/wallet.dart';
 
 class AccountDTO {
@@ -23,11 +24,13 @@ class RequestDTO {
     this.source,
     this.destination,
     this.amount,
-    this.recipient,
+    this.recipient, {
-  );
+    this.payoutInput,
+  });
   final String kind, source, recipient;
   final String? destination;
   final int amount;
+  final DestinationInputDTO? payoutInput;
 }
 
 class QuoteDTO {
@@ -39,12 +42,16 @@ class QuoteDTO {
     this.credit,
     this.expires,
     this.numerator,
-    this.denominator,
+    this.denominator, {
-  );
+    this.payoutSnapshot,
+    this.payoutTerms,
+  });
   final String id;
   final RequestDTO request;
   final int fee, debit, credit, numerator, denominator;
   final DateTime expires;
+  final DestinationDTO? payoutSnapshot;
+  final PayoutTermsDTO? payoutTerms;
 }
 
 class OperationDTO {
@@ -78,14 +85,28 @@ abstract final class WalletMapper {
     payoutLabel: d.payoutLabel,
     canFund: d.canFund,
   );
-  static RequestDTO request(TransferRequest r) =>
+  static RequestDTO request(
-      RequestDTO(r.kind.name, r.source, r.destination, r.amount, r.recipient);
+    TransferRequest r, {
+    bool includePayoutInput = true,
+  }) => RequestDTO(
+    r.kind.name,
+    r.source,
+    r.destination,
+    r.amount,
+    r.recipient,
+    payoutInput: !includePayoutInput || r.payoutDestination == null
+        ? null
+        : DestinationInputMapper.toDTO(r.payoutDestination!),
+  );
   static TransferRequest fromRequest(RequestDTO d) => TransferRequest(
     kind: TransferKind.values.byName(d.kind),
     source: d.source,
     destination: d.destination,
     amount: d.amount,
     recipient: d.recipient,
+    payoutDestination: d.payoutInput == null
+        ? null
+        : DestinationInputMapper.fromDTO(d.payoutInput!),
   );
   static Quote quote(QuoteDTO d) => Quote(
     id: d.id,
@@ -96,6 +117,17 @@ abstract final class WalletMapper {
     expiresAt: d.expires,
     rateNumerator: d.numerator,
     rateDenominator: d.denominator,
+    payoutTerms: d.payoutTerms == null
+        ? null
+        : PayoutTerms(
+            d.payoutTerms!.amount,
+            d.payoutTerms!.precision,
+            d.payoutTerms!.assetLabel,
+            d.payoutTerms!.expectedSeconds,
+          ),
+    payoutSnapshot: d.payoutSnapshot == null
+        ? null
+        : DestinationMapper.fromDTO(d.payoutSnapshot!),
   );
   static WalletOperation operation(OperationDTO d) => WalletOperation(
     id: d.id,
@@ -105,3 +137,14 @@ abstract final class WalletMapper {
   );
   static AccountProfile profile(ProfileDTO dto) => AccountProfile(dto.locale);
 }
+
+class PayoutTermsDTO {
+  const PayoutTermsDTO(
+    this.amount,
+    this.precision,
+    this.assetLabel,
+    this.expectedSeconds,
+  );
+  final int amount, precision, expectedSeconds;
+  final String assetLabel;
+}

frontend/packages/sxchnge_wallet/lib/sxchnge_wallet.dart

@@ -6,3 +6,15 @@ export 'src/services/dummy.dart';
 export 'src/providers/limits.dart';
 export 'src/services/backend.dart';
 export 'src/services/factors.dart';
+
+export 'src/destinations/models.dart';
+export 'src/destinations/service.dart';
+export 'src/destinations/dummy.dart';
+export 'src/destinations/provider.dart';
+export 'src/destinations/bank_paste.dart';
+export 'src/destinations/unavailable.dart';
+export 'src/destinations/form.dart';
+export 'src/destinations/search.dart';
+export 'src/destinations/selection.dart';
+export 'src/destinations/management.dart';
+export 'src/destinations/key.dart';

frontend/packages/sxchnge_wallet/test/backend_test.dart

@@ -235,11 +235,52 @@ void main() {
     addTearDown(draft.dispose);
     await wallet.refresh();
     expect(draft.source, 'ledger');
-    expect(draft.recipient, 'method');
+    expect(draft.recipient, isEmpty);
     expect(draft.hasDraft, false);
+    draft.change(recipient: 'method');
+    expect(draft.hasDraft, true);
     draft.change(amount: '20.01');
     await draft.review();
     await draft.submit(approval: const FactorGrant('approved-intent-key'));
     expect(draft.result, isNotNull);
   });
+
+  test('new typed destinations cannot be silently dropped into the legacy live API', () async {
+    var calls = 0;
+    final service = BackendWalletService(
+      baseUri: Uri.parse('https://example.test'),
+      accessToken: () => 'test-token',
+      client: MockClient((request) async {
+        calls++;
+        return http.Response('{}', 500);
+      }),
+    );
+    addTearDown(service.close);
+    await expectLater(
+      service.quote(
+        const TransferRequest(
+          kind: TransferKind.payout,
+          source: 'ledger',
+          amount: 100,
+          payoutDestination: OneTimeDestination(
+            CryptoDestination(
+              assetId: 'asset',
+              networkId: 'network',
+              address: 'address',
+              assetLabel: 'Asset',
+              networkLabel: 'Network',
+            ),
+          ),
+        ),
+      ),
+      throwsA(
+        isA<WalletException>().having(
+          (e) => e.code,
+          'code',
+          WalletError.unsupported,
+        ),
+      ),
+    );
+    expect(calls, 0);
+  });
 }

frontend/packages/sxchnge_wallet/test/destinations_test.dart

@@ -0,0 +1,617 @@
+import 'package:flutter_test/flutter_test.dart';
+
+import 'package:sxchnge_analytics/sxchnge_analytics.dart';
+
+import 'package:sxchnge_kyc/sxchnge_kyc.dart';
+
+import 'package:sxchnge_wallet/sxchnge_wallet.dart';
+
+import 'package:sxchnge_wallet/src/destinations/transport.dart';
+
+const crypto = CryptoDestination(
+  assetId: 'demo:ethereum:native',
+  networkId: 'eip155:1',
+  address: '0x1234567890123456789012345678901234567890',
+  assetLabel: 'Untrusted label',
+  networkLabel: 'Untrusted network',
+);
+const input = OneTimeDestination(crypto);
+const card = CardDestination(
+  capture: 'demo-card-ready',
+  brand: 'Untrusted brand',
+  last4: '9999',
+  expiryMonth: 1,
+  expiryYear: 1900,
+);
+const bank = Bank(
+  bik: '044525225',
+  name: 'Demo Bank',
+  city: 'Moscow',
+  correspondent: '30101810400000000225',
+  revision: 'demo-1',
+);
+const russian = RussianBankDestination(
+  firstName: 'Anna Maria',
+  lastName: 'de la Cruz',
+  bank: bank,
+  account: '40817810899910004312',
+);
+Matcher issue(DestinationIssue value) =>
+    throwsA(isA<DestinationException>().having((e) => e.issue, 'issue', value));
+void main() {
+  late DummyDestinationService service;
+  setUp(() {
+    service = DummyDestinationService();
+  });
+  test('one-time validation, quotation and acceptance never save', () async {
+    final lease = await service.prepare(
+      input,
+      const PayoutContext('eur', amount: 100),
+    );
+    expect(lease.snapshot.display, contains('ETH'));
+    service.accept(lease);
+    expect(await service.list(), isEmpty);
+  });
+  test('idempotency replays creation and rejects changed payload', () async {
+    final first = await service.create(
+      crypto,
+      'Private name',
+      'creation-key-000001',
+    );
+    expect(first.outcome, SaveOutcome.created);
+    expect(
+      (await service.create(
+        crypto,
+        'Private name',
+        'creation-key-000001',
+      )).destinationId,
+      first.destinationId,
+    );
+    await expectLater(
+      service.create(crypto, 'Changed', 'creation-key-000001'),
+      issue(DestinationIssue.conflict),
+    );
+    expect((await service.list()).length, 1);
+  });
+  test(
+    'duplicate outcome is stable after rename, removal and concurrent create',
+    () async {
+      final results = await Future.wait(
+        List.generate(
+          8,
+          (i) => service.create(crypto, 'Name $i', 'creation-key-00000$i'),
+        ),
+      );
+      expect(results.where((r) => r.outcome == SaveOutcome.created).length, 1);
+      expect(results.map((r) => r.destinationId).toSet().length, 1);
+      final d = await service.get(results.first.destinationId);
+      final renamed = await service.rename(
+        d.id,
+        'Original stays',
+        d.metadataRevision,
+      );
+      await service.remove(
+        d.id,
+        renamed.metadataRevision,
+        renamed.executionRevision,
+      );
+      final replay = await service.create(
+        crypto,
+        'Name 1',
+        'creation-key-000001',
+      );
+      expect(replay.outcome, SaveOutcome.duplicate);
+      expect(replay.destinationId, d.id);
+      expect(
+        (await service.creation('creation-key-000001'))!.outcome,
+        SaveOutcome.duplicate,
+      );
+    },
+  );
+  test(
+    'save timeout reconciles a created record separately from duplicate',
+    () async {
+      service.loseNextSaveResponse = true;
+      await expectLater(
+        service.create(crypto, '', 'creation-key-000001'),
+        issue(DestinationIssue.uncertain),
+      );
+      expect(
+        (await service.creation('creation-key-000001'))!.outcome,
+        SaveOutcome.created,
+      );
+      service.loseNextSaveResponse = true;
+      await expectLater(
+        service.create(crypto, '', 'creation-key-000002'),
+        issue(DestinationIssue.uncertain),
+      );
+      expect(
+        (await service.creation('creation-key-000002'))!.outcome,
+        SaveOutcome.duplicate,
+      );
+    },
+  );
+  test('customer isolation includes duplicates, attempt lookup, reads and mutations', () async {
+    final memory = DestinationMemory();
+    final a = DummyDestinationService(customer: 'a', memory: memory);
+    final b = DummyDestinationService(customer: 'b', memory: memory);
+    final saved = await a.create(crypto, 'A', 'creation-key-000001');
+    expect(await b.creation('creation-key-000001'), isNull);
+    await expectLater(
+      b.get(saved.destinationId),
+      issue(DestinationIssue.removed),
+    );
+    await expectLater(
+      b.rename(saved.destinationId, 'B', 1),
+      issue(DestinationIssue.removed),
+    );
+    await expectLater(
+      b.remove(saved.destinationId, 1, 1),
+      issue(DestinationIssue.removed),
+    );
+    expect(
+      (await b.create(crypto, 'B', 'creation-key-000001')).outcome,
+      SaveOutcome.created,
+    );
+  });
+  test('metadata concurrency never changes execution revision or invalidates lease', () async {
+    final result = await service.create(crypto, '', 'creation-key-000001');
+    final d = await service.get(result.destinationId);
+    final lease = await service.prepare(d.input, const PayoutContext('eur'));
+    final changed = await service.rename(d.id, 'New label', d.metadataRevision);
+    expect(changed.executionRevision, d.executionRevision);
+    expect(changed.metadataRevision, d.metadataRevision + 1);
+    service.accept(lease);
+    await expectLater(
+      service.rename(d.id, 'Stale', d.metadataRevision),
+      issue(DestinationIssue.conflict),
+    );
+  });
+  test(
+    'removal invalidates draft lease and never mutates previous snapshots',
+    () async {
+      final result = await service.create(crypto, '', 'creation-key-000001');
+      final d = await service.get(result.destinationId);
+      final lease = await service.prepare(d.input, const PayoutContext('eur'));
+      await service.remove(d.id, d.metadataRevision, d.executionRevision);
+      expect(() => service.accept(lease), issue(DestinationIssue.removed));
+      expect(lease.snapshot.review, contains(crypto.address));
+      expect(await service.list(), isEmpty);
+      expect(service.memory.audit.map((a) => a.action), contains('remove'));
+    },
+  );
+  test(
+    'requirements and contextual availability are rechecked at acceptance',
+    () async {
+      final result = await service.create(crypto, '', 'creation-key-000001');
+      final d = await service.get(result.destinationId);
+      final lease = await service.prepare(d.input, const PayoutContext('eur'));
+      service.availability[d.id] = const PayoutEligibility(
+        EligibilityState.temporarilyUnavailable,
+        reason: DestinationIssue.unavailable,
+      );
+      expect(() => service.accept(lease), issue(DestinationIssue.unavailable));
+      service.availability.clear();
+      service.requirementsRevision++;
+      expect(() => service.accept(lease), issue(DestinationIssue.conflict));
+    },
+  );
+  test(
+    'network and canonical token identity distinguish duplicate addresses',
+    () async {
+      final ids = <String>{};
+      for (final a in DummyDestinationService.assets.where(
+        (a) => a.networkId.startsWith('eip155:'),
+      )) {
+        final result = await service.create(
+          CryptoDestination(
+            assetId: a.id,
+            networkId: a.networkId,
+            address: crypto.address,
+            memo: '',
+            assetLabel: a.label,
+            networkLabel: a.networkLabel,
+          ),
+          '',
+          destinationKey(),
+        );
+        ids.add(result.destinationId);
+      }
+      expect(ids.length, 4);
+    },
+  );
+  test(
+    'address presentation preserves case; normalization is service-owned',
+    () async {
+      const upper = CryptoDestination(
+        assetId: 'demo:ethereum:native',
+        networkId: 'eip155:1',
+        address: '0xABCDEFabcdefABCDEFabcdefABCDEFabcdefABCD',
+        assetLabel: 'ETH',
+        networkLabel: 'Ethereum',
+      );
+      final first = await service.create(upper, '', 'creation-key-000001');
+      final lower = CryptoDestination(
+        assetId: upper.assetId,
+        networkId: upper.networkId,
+        address: upper.address.toLowerCase(),
+        assetLabel: 'ETH',
+        networkLabel: 'Ethereum',
+      );
+      expect(
+        (await service.create(lower, '', 'creation-key-000002')).destinationId,
+        first.destinationId,
+      );
+      expect(
+        (await service.get(first.destinationId)).details.review,
+        contains(upper.address),
+      );
+    },
+  );
+  test('memo requirements are validated before saving', () async {
+    const d = CryptoDestination(
+      assetId: 'demo:xrp:native',
+      networkId: 'xrpl:mainnet',
+      address: 'r123456789ABCDEFGHJKLMNPQRSTU',
+      assetLabel: 'XRP',
+      networkLabel: 'XRP Ledger',
+    );
+    await expectLater(
+      service.create(d, '', 'creation-key-000001'),
+      issue(DestinationIssue.invalid),
+    );
+    expect(await service.list(), isEmpty);
+  });
+  test('card captures never trust user display metadata; recovery preserves record', () async {
+    final r = await service.create(card, '', 'creation-key-000001');
+    final saved = await service.get(r.destinationId);
+    expect(saved.details.display, contains('4242'));
+    expect(saved.details.display, isNot(contains('9999')));
+    const recovery = CardDestination(
+      capture: 'demo-card-recover',
+      brand: '',
+      last4: '',
+      expiryMonth: 0,
+      expiryYear: 0,
+    );
+    final other = DummyDestinationService();
+    final pending = await other.create(recovery, '', 'creation-key-000001');
+    final d = await other.get(pending.destinationId);
+    expect(
+      (await other.assess(d.input, const PayoutContext('eur'))).state,
+      EligibilityState.requiresAction,
+    );
+    expect((await other.list()).length, 1);
+  });
+  test('unreliable card fingerprint does not merge by last four', () async {
+    const d = CardDestination(
+      capture: 'demo-card-unknown',
+      brand: '',
+      last4: '',
+      expiryMonth: 0,
+      expiryYear: 0,
+    );
+    final a = await service.create(d, '', 'creation-key-000001');
+    final b = await service.create(d, '', 'creation-key-000002');
+    expect(a.destinationId, isNot(b.destinationId));
+    expect(b.outcome, SaveOutcome.created);
+  });
+  test(
+    'bank control key and directory changes are separate from ownership',
+    () async {
+      expect(validBankAccount('40817810899910004312', bank.bik), isTrue);
+      final r = await service.create(russian, '', 'creation-key-000001');
+      final saved = await service.get(r.destinationId);
+      expect(saved.ownership.verified, isFalse);
+      service.directory = [
+        const Bank(
+          bik: '044525225',
+          name: 'New cosmetic name',
+          city: 'Moscow',
+          correspondent: '30101810400000000225',
+          revision: 'demo-2',
+        ),
+      ];
+      expect(
+        (await service.assess(
+          saved.input,
+          const PayoutContext('eur'),
+        )).eligible,
+        isTrue,
+      );
+      service.directory = [
+        const Bank(
+          bik: '044525225',
+          name: 'New bank',
+          city: 'Moscow',
+          correspondent: 'changed',
+          revision: 'demo-3',
+        ),
+      ];
+      expect(
+        (await service.assess(saved.input, const PayoutContext('eur'))).reason,
+        DestinationIssue.bankChanged,
+      );
+      expect(
+        (await service.get(saved.id)).details.review,
+        contains(bank.correspondent),
+      );
+    },
+  );
+  test(
+    'paste conflicts are never guessed and full holder names remain unsplit',
+    () {
+      final parsed = BankPaste.parse(
+        'БИК: 044525225\nБИК: 044525999\nНомер счета: 0000 1234\nФИО: Anna Maria de la Cruz',
+      );
+      expect(parsed.conflicts, contains('bik'));
+      expect(parsed.values, isNot(contains('bik')));
+      expect(parsed.values['account'], '00001234');
+      expect(parsed.values['holder'], 'Anna Maria de la Cruz');
+      expect(parsed.values, isNot(contains('firstName')));
+    },
+  );
+  test('all details round trip through DTO mapper', () {
+    for (final d in <DestinationDetails>[crypto, card, russian]) {
+      expect(DestinationMapper.clone(d).review, d.review);
+    }
+  });
+  test(
+    'optional save failure can continue one-time without claiming saved',
+    () async {
+      final p = DestinationFormProvider(
+        service,
+        DummyAnalyticsService(),
+        context: const PayoutContext('eur'),
+      );
+      addTearDown(p.dispose);
+      p.change(crypto);
+      p.preferences(save: true);
+      service.nextSaveError = DestinationIssue.conflict;
+      await p.proceed();
+      expect(p.savingFailed, isTrue);
+      expect(p.saved, isNull);
+      await p.proceed(withoutSaving: true);
+      expect(p.result, isA<OneTimeDestination>());
+      expect(await service.list(), isEmpty);
+    },
+  );
+  test('saving and contextual eligibility have independent outcomes', () async {
+    final p = DestinationFormProvider(
+      service,
+      DummyAnalyticsService(),
+      context: const PayoutContext('unsupported'),
+    );
+    addTearDown(p.dispose);
+    p.change(crypto);
+    p.preferences(save: true);
+    await p.proceed();
+    expect(p.saved!.outcome, SaveOutcome.created);
+    expect(p.eligibility!.state, EligibilityState.unsupported);
+    expect(p.result, isNull);
+    expect(p.error, isNull);
+  });
+  test('explicit duplicate reuse preserves existing nickname', () async {
+    final first = await service.create(
+      crypto,
+      'Original',
+      'creation-key-000001',
+    );
+    final p = DestinationFormProvider(
+      service,
+      DummyAnalyticsService(),
+      context: const PayoutContext('eur'),
+    );
+    addTearDown(p.dispose);
+    p.change(crypto);
+    p.preferences(save: true, nickname: 'New');
+    await p.proceed();
+    expect(p.saved!.outcome, SaveOutcome.duplicate);
+    expect(p.result, isNull);
+    await p.useExisting();
+    expect((p.result as SavedReference).id, first.destinationId);
+    expect((await service.get(first.destinationId)).nickname, 'Original');
+  });
+  test(
+    'wallet acceptance rejects removed destination without debiting',
+    () async {
+      final wallet = DummyWalletService(
+        DummyIdentityService(delay: Duration.zero),
+        delay: Duration.zero,
+        destinations: service,
+      );
+      final created = await service.create(crypto, '', 'creation-key-000001');
+      final d = await service.get(created.destinationId);
+      final q = await wallet.quote(
+        TransferRequest(
+          kind: TransferKind.payout,
+          source: 'eur',
+          amount: 1000,
+          payoutDestination: d.input,
+        ),
+      );
+      await service.remove(d.id, d.metadataRevision, d.executionRevision);
+      await expectLater(
+        wallet.submit(q.id, 'request'),
+        throwsA(
+          isA<WalletException>().having(
+            (e) => e.code,
+            'code',
+            WalletError.destinationChanged,
+          ),
+        ),
+      );
+      expect((await wallet.fetch()).accounts.first.available, 7500);
+      expect((await wallet.fetch()).operations, isEmpty);
+    },
+  );
+
+  test('large collections search safe metadata and sort recent use without choosing', () async {
+    for (var i = 0; i < 240; i++) {
+      await service.create(
+        CryptoDestination(
+          assetId: crypto.assetId,
+          networkId: crypto.networkId,
+          address: '0x' + i.toRadixString(16).padLeft(40, '0'),
+          assetLabel: 'ETH',
+          networkLabel: 'Ethereum',
+        ),
+        'Wallet ' + i.toString(),
+        destinationKey(),
+      );
+    }
+    final rows = await service.list();
+    service.accept(
+      await service.prepare(rows.last.input, const PayoutContext('eur')),
+    );
+    final p = DestinationsProvider(service);
+    addTearDown(p.dispose);
+    await p.refresh();
+    expect(p.search('', DestinationType.crypto).first.id, rows.last.id);
+    expect(
+      p.search('Wallet 239', DestinationType.crypto).single.id,
+      rows.last.id,
+    );
+    expect(p.search('not found', DestinationType.crypto), isEmpty);
+  });
+  test('cards without supported reuse or recovery cannot be saved', () async {
+    service.reusableCards = false;
+    service.cardRecovery = false;
+    expect(
+      (await service.assess(
+        const OneTimeDestination(card),
+        const PayoutContext('eur'),
+      )).canSave,
+      isFalse,
+    );
+    await expectLater(
+      service.create(card, '', 'creation-key-000001'),
+      issue(DestinationIssue.unsupported),
+    );
+    expect(await service.list(), isEmpty);
+  });
+  test('existing card survives loss of its only reusable binding', () async {
+    final result = await service.create(card, '', 'creation-key-000001');
+    final d = await service.get(result.destinationId);
+    expect((d.details as CardDestination).capture, isEmpty);
+    final old = await service.prepare(d.input, const PayoutContext('eur'));
+    service.memory.records[service.customer]![d.id] = SavedDestination(
+      id: d.id,
+      details: d.details,
+      metadataRevision: d.metadataRevision,
+      executionRevision: d.executionRevision + 1,
+      bindings: [
+        const ProviderBinding(
+          reference: 'binding',
+          state: BindingState.revoked,
+          reusable: true,
+          recoverable: true,
+        ),
+      ],
+    );
+    final changed = await service.get(d.id);
+    expect(
+      (await service.assess(changed.input, const PayoutContext('eur'))).state,
+      EligibilityState.requiresAction,
+    );
+    expect(() => service.accept(old), issue(DestinationIssue.conflict));
+    expect((await service.list()).length, 1);
+    service.cardRecovery = false;
+    expect(
+      (await service.assess(changed.input, const PayoutContext('eur'))).state,
+      EligibilityState.unsupported,
+    );
+  });
+  test(
+    'accepted payout snapshot survives nickname changes and removal',
+    () async {
+      final wallet = DummyWalletService(
+        DummyIdentityService(delay: Duration.zero),
+        delay: Duration.zero,
+        destinations: service,
+      );
+      final result = await service.create(crypto, '', 'creation-key-000001');
+      final d = await service.get(result.destinationId);
+      final q = await wallet.quote(
+        TransferRequest(
+          kind: TransferKind.payout,
+          source: 'eur',
+          amount: 1000,
+          payoutDestination: d.input,
+        ),
+      );
+      final renamed = await service.rename(
+        d.id,
+        'After quote',
+        d.metadataRevision,
+      );
+      final accepted = await wallet.submit(q.id, 'payout-key');
+      await service.remove(
+        d.id,
+        renamed.metadataRevision,
+        renamed.executionRevision,
+      );
+      expect((await wallet.fetch()).operations.single.id, accepted.id);
+      expect(accepted.quote.payoutSnapshot!.review, contains(crypto.address));
+    },
+  );
+
+  test('card recovery preserves identity, invalidates execution and replays idempotently', () async {
+    const capture = CardDestination(
+      capture: 'demo-card-recover',
+      brand: '',
+      last4: '',
+      expiryMonth: 0,
+      expiryYear: 0,
+    );
+    final created = await service.create(
+      capture,
+      'Keep label',
+      'creation-key-000001',
+    );
+    final d = await service.get(created.destinationId);
+    final restored = await service.restoreCard(
+      d.id,
+      d.executionRevision,
+      card,
+      'card-recovery-key-0001',
+    );
+    expect(restored.id, d.id);
+    expect(restored.nickname, d.nickname);
+    expect(restored.metadataRevision, d.metadataRevision);
+    expect(restored.executionRevision, d.executionRevision + 1);
+    expect(
+      (await service.assess(
+        restored.input,
+        const PayoutContext('eur'),
+      )).eligible,
+      isTrue,
+    );
+    expect(
+      (await service.restoreCard(
+        d.id,
+        d.executionRevision,
+        card,
+        'card-recovery-key-0001',
+      )).executionRevision,
+      restored.executionRevision,
+    );
+    expect((await service.list()).length, 1);
+    const unidentified = CardDestination(
+      capture: 'demo-card-unknown',
+      brand: '',
+      last4: '',
+      expiryMonth: 0,
+      expiryYear: 0,
+    );
+    await expectLater(
+      service.restoreCard(
+        d.id,
+        restored.executionRevision,
+        unidentified,
+        'card-recovery-key-0002',
+      ),
+      issue(DestinationIssue.replacementRequired),
+    );
+  });
+}

frontend/packages/sxchnge_wallet/test/two_factor_test.dart

@@ -27,6 +27,15 @@ void main() {
             amount: 1000,
             destination: kind == TransferKind.exchange ? 'usd' : null,
             recipient: 'Sample recipient',
+            payoutDestination: OneTimeDestination(
+              CryptoDestination(
+                assetId: 'demo:ethereum:native',
+                networkId: 'eip155:1',
+                address: '0x1234567890123456789012345678901234567890',
+                assetLabel: 'ETH',
+                networkLabel: 'Ethereum',
+              ),
+            ),
           ),
         );
         await expectLater(
@@ -59,6 +68,15 @@ void main() {
         source: 'eur',
         amount: 1000,
         recipient: 'Sample recipient',
+        payoutDestination: OneTimeDestination(
+          CryptoDestination(
+            assetId: 'demo:ethereum:native',
+            networkId: 'eip155:1',
+            address: '0x1234567890123456789012345678901234567890',
+            assetLabel: 'ETH',
+            networkLabel: 'Ethereum',
+          ),
+        ),
       ),
     );
     final c = (await factor.begin(FactorPurpose.payout, q.id))!;
@@ -85,6 +103,15 @@ void main() {
         source: 'eur',
         amount: 1000,
         recipient: 'Sample recipient',
+        payoutDestination: OneTimeDestination(
+          CryptoDestination(
+            assetId: 'demo:ethereum:native',
+            networkId: 'eip155:1',
+            address: '0x1234567890123456789012345678901234567890',
+            assetLabel: 'ETH',
+            networkLabel: 'Ethereum',
+          ),
+        ),
       ),
     );
     final c = (await factor.begin(FactorPurpose.payout, 'different-quote'))!;

frontend/packages/sxchnge_wallet/test/wallet_test.dart

@@ -39,6 +39,15 @@ void main() {
         destination: to,
         amount: amount,
         recipient: recipient,
+        payoutDestination: OneTimeDestination(
+          CryptoDestination(
+            assetId: 'demo:ethereum:native',
+            networkId: 'eip155:1',
+            address: '0x1234567890123456789012345678901234567890',
+            assetLabel: 'ETH',
+            networkLabel: 'Ethereum',
+          ),
+        ),
       ),
     );
     return s.submit(q.id, key);
@@ -107,6 +116,15 @@ void main() {
         source: 'eur',
         amount: 7000,
         recipient: 'Sample recipient',
+        payoutDestination: OneTimeDestination(
+          CryptoDestination(
+            assetId: 'demo:ethereum:native',
+            networkId: 'eip155:1',
+            address: '0x1234567890123456789012345678901234567890',
+            assetLabel: 'ETH',
+            networkLabel: 'Ethereum',
+          ),
+        ),
       ),
     );
     now = now.add(const Duration(seconds: 61));
@@ -127,6 +145,15 @@ void main() {
         source: 'eur',
         amount: 6000,
         recipient: 'Sample recipient',
+        payoutDestination: OneTimeDestination(
+          CryptoDestination(
+            assetId: 'demo:ethereum:native',
+            networkId: 'eip155:1',
+            address: '0x1234567890123456789012345678901234567890',
+            assetLabel: 'ETH',
+            networkLabel: 'Ethereum',
+          ),
+        ),
       ),
     );
     final b = await s.quote(
@@ -135,6 +162,15 @@ void main() {
         source: 'eur',
         amount: 6000,
         recipient: 'Sample recipient',
+        payoutDestination: OneTimeDestination(
+          CryptoDestination(
+            assetId: 'demo:ethereum:native',
+            networkId: 'eip155:1',
+            address: '0x1234567890123456789012345678901234567890',
+            assetLabel: 'ETH',
+            networkLabel: 'Ethereum',
+          ),
+        ),
       ),
     );
     await s.submit(a.id, 'first');
@@ -160,6 +196,15 @@ void main() {
           source: 'eur',
           amount: 11000,
           recipient: 'Sample recipient',
+          payoutDestination: OneTimeDestination(
+            CryptoDestination(
+              assetId: 'demo:ethereum:native',
+              networkId: 'eip155:1',
+              address: '0x1234567890123456789012345678901234567890',
+              assetLabel: 'ETH',
+              networkLabel: 'Ethereum',
+            ),
+          ),
         ),
       ),
       throwsA(