diff --git a/features/bounties/hooks/use-bounty-escrow.ts b/features/bounties/hooks/use-bounty-escrow.ts
new file mode 100644
index 000000000..c763e7da8
--- /dev/null
+++ b/features/bounties/hooks/use-bounty-escrow.ts
@@ -0,0 +1,259 @@
+'use client';
+
+import { useState, useCallback } from 'react';
+import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query';
+import { toast } from 'sonner';
+import { reportError } from '@/lib/error-reporting';
+
+const BOUNDED_PREFIX = ['bounties'] as const;
+
+type BountySummary = {
+  id: string;
+  title: string;
+  description: string;
+  reward: string;
+  status: 'open' | 'in_progress' | 'completed';
+  createdAt: string;
+  claimCount?: number;
+};
+
+type BountyApplication = {
+  id: string;
+  bountyId: string;
+  message: string;
+  status: 'pending' | 'accepted' | 'rejected';
+  submittedAt: string;
+};
+
+type ParticipantActivityItem =
+  | { kind: 'application'; data: BountyApplication }
+  | { kind: 'submission'; data: { id: string; bountyId: string; status: string } };
+
+async function request<T>(path: string, init?: RequestInit): Promise<T> {
+  const res = await fetch(path, {
+    ...init,
+    headers: {
+      'Content-Type': 'application/json',
+      ...(init?.headers ?? {}),
+    },
+  });
+  if (!res.ok) {
+    const body = await res.text().catch(() => '');
+    throw new Error(body || `Request failed: ${res.status}`);
+  }
+  if (res.status === 204) return undefined as T;
+  return (await res.json()) as T;
+}
+
+export function useBountiesList(params?: { page?: number; limit?: number }) {
+  return useQuery({
+    queryKey: [...BOUNDED_PREFIX, 'list', params],
+    queryFn: async (): Promise<{ bounties: BountySummary[]; pagination: Record<string, unknown> }> => {
+      const search = new URLSearchParams({ page: String(params?.page ?? 1), limit: String(params?.limit ?? 20) });
+      const data = await request<{ bounties: BountySummary[]; pagination: Record<string, unknown> }>(`/api/bounties?${search}`);
+      return { bounties: data.bounties ?? [], pagination: data.pagination ?? {} };
+    },
+    staleTime: 30_000,
+  });
+}
+
+export function useBounty(id: string) {
+  return useQuery({
+    queryKey: [...BOUNDED_PREFIX, 'detail', id],
+    queryFn: async () => {
+      const data = await request<{ bounty: BountySummary }>(`/api/bounties/${encodeURIComponent(id)}`);
+      return data.bounty;
+    },
+    enabled: !!id,
+    staleTime: 30_000,
+  });
+}
+
+export function useMyBountyApplications(bountyId: string) {
+  return useQuery({
+    queryKey: [...BOUNDED_PREFIX, 'my-applications', bountyId],
+    queryFn: async () => {
+      const data = await request<{ applications: BountyApplication[] }>(`/api/bounties/${encodeURIComponent(bountyId)}/applications/me`);
+      return data.applications ?? [];
+    },
+    enabled: !!bountyId,
+    staleTime: 20_000,
+  });
+}
+
+export function useApplyToBounty(bountyId: string) {
+  const queryClient = useQueryClient();
+  return useMutation({
+    mutationFn: async (message: string) => {
+      const data = await request<{ application: BountyApplication }>(`/api/bounties/${encodeURIComponent(bountyId)}/applications`, {
+        method: 'POST',
+        body: JSON.stringify({ message }),
+      });
+      return data.application;
+    },
+    onSuccess: () => {
+      queryClient.invalidateQueries({ queryKey: [...BOUNDED_PREFIX, 'my-applications', bountyId] });
+      toast.success('Application submitted');
+    },
+    onError: (err: unknown) => {
+      const message = err instanceof Error ? err.message : 'Failed to apply';
+      reportError(err, { context: 'bounties-applyToBounty', bountyId });
+      toast.error(message);
+    },
+  });
+}
+
+export function useJoinCompetition(bountyId: string) {
+  const queryClient = useQueryClient();
+  return useMutation({
+    mutationFn: async (payload?: { teamName?: string; message?: string }) => {
+      const data = await request<{ application: BountyApplication }>(`/api/bounties/${encodeURIComponent(bountyId)}/join`, {
+        method: 'POST',
+        body: JSON.stringify({ type: 'TEAM', ...payload }),
+      });
+      return data.application;
+    },
+    onSuccess: () => {
+      queryClient.invalidateQueries({ queryKey: [...BOUNDED_PREFIX, 'my-applications', bountyId] });
+      toast.success('Joined bounty');
+    },
+    onError: (err: unknown) => {
+      const message = err instanceof Error ? err.message : 'Failed to join competition';
+      reportError(err, { context: 'bounties-joinCompetition', bountyId });
+      toast.error(message);
+    },
+  });
+}
+
+export function useEditApplication(bountyId: string, applicationId: string) {
+  const queryClient = useQueryClient();
+  return useMutation({
+    mutationFn: async (patch: Partial<Pick<BountyApplication, 'message'>>) => {
+      const data = await request<{ application: BountyApplication }>(`/api/bounties/${encodeURIComponent(bountyId)}/applications/${encodeURIComponent(applicationId)}`, {
+        method: 'PATCH',
+        body: JSON.stringify(patch),
+      });
+      return data.application;
+    },
+    onSuccess: () => {
+      queryClient.invalidateQueries({ queryKey: [...BOUNDED_PREFIX, 'my-applications', bountyId] });
+      toast.success('Application updated');
+    },
+    onError: (err: unknown) => {
+      const message = err instanceof Error ? err.message : 'Failed to update application';
+      reportError(err, { context: 'bounties-editApplication', bountyId, applicationId });
+      toast.error(message);
+    },
+  });
+}
+
+export function useWithdrawApplication(bountyId: string, applicationId: string) {
+  const queryClient = useQueryClient();
+  return useMutation({
+    mutationFn: async () => {
+      await request(`/api/bounties/${encodeURIComponent(bountyId)}/applications/${encodeURIComponent(applicationId)}`, {
+        method: 'DELETE',
+      });
+    },
+    onSuccess: () => {
+      queryClient.invalidateQueries({ queryKey: [...BOUNDED_PREFIX, 'my-applications', bountyId] });
+      toast.success('Application withdrawn');
+    },
+    onError: (err: unknown) => {
+      const message = err instanceof Error ? err.message : 'Failed to withdraw application';
+      reportError(err, { context: 'bounties-withdrawApplication', bountyId, applicationId });
+      toast.error(message);
+    },
+  });
+}
+
+async function runEscrowOp<T>(payload: Record<string, unknown>): Promise<T> {
+  const data = await request<T>('/api/escrow/ops', {
+    method: 'POST',
+    body: JSON.stringify({ scope: 'participant', mode: 'MANAGED', ...payload }),
+  });
+  return data;
+}
+
+export function useSubmitBounty(bountyId: string) {
+  const queryClient = useQueryClient();
+  return useMutation({
+    mutationFn: async (payload: { description: string; links?: Array<{ type?: string; url: string }> }) => {
+      const description = payload?.description;
+      const links = payload?.links;
+      if (!description) {
+        throw new Error('Description is required to submit bounty work');
+      }
+      const result = await runEscrowOp<{ submission: { id: string; status: string } }>({
+        bountyId,
+        description,
+        links,
+      });
+      if (!result || !('submission' in result)) {
+        throw new Error('Escrow operation did not return a submission');
+      }
+      return result as { submission: { id: string; status: string } };
+    },
+    onSuccess: (result) => {
+      queryClient.invalidateQueries({ queryKey: [...BOUNDED_PREFIX, 'detail', bountyId] });
+      toast.success(`Submission recorded${result?.submission?.id ? ': ' + result.submission.id : ''}`);
+    },
+    onError: (err: unknown) => {
+      const message = err instanceof Error ? err.message : 'Failed to submit bounty work';
+      reportError(err, { context: 'bounties-submitBounty', bountyId });
+      toast.error(message);
+    },
+  });
+}
+
+export function useWithdrawSubmission(bountyId: string, submissionId: string) {
+  const queryClient = useQueryClient();
+  return useMutation({
+    mutationFn: async () => {
+      await request(`/api/bounties/${encodeURIComponent(bountyId)}/submissions/${encodeURIComponent(submissionId)}`, {
+        method: 'DELETE',
+      });
+    },
+    onSuccess: () => {
+      queryClient.invalidateQueries({ queryKey: [...BOUNDED_PREFIX, 'detail', bountyId] });
+      toast.success('Submission withdrawn');
+    },
+    onError: (err: unknown) => {
+      const message = err instanceof Error ? err.message : 'Failed to withdraw submission';
+      reportError(err, { context: 'bounties-withdrawSubmission', bountyId, submissionId });
+      toast.error(message);
+    },
+  });
+}
+
+type ParticipantSubmission = { id: string; bountyId: string; status: string };
+
+type ParticipantActivityItem =
+  | { kind: 'application'; data: BountyApplication }
+  | { kind: 'submission'; data: ParticipantSubmission };
+
+export function useMyBountyActivity(bountyId: string) {
+  const applications = useMyBountyApplications(bountyId);
+  const submissions = useQuery({
+    queryKey: [...BOUNDED_PREFIX, 'my-submissions', bountyId],
+    queryFn: async (): Promise<ParticipantSubmission[]> => {
+      const data = await request<{ submissions: ParticipantSubmission[] }>(`/api/bounties/${encodeURIComponent(bountyId)}/submissions/me`);
+      return data.submissions ?? [];
+    },
+    enabled: !!bountyId,
+    staleTime: 20_000,
+  });
+
+  return useQuery({
+    queryKey: [...BOUNDED_PREFIX, 'my-activity', bountyId],
+    queryFn: async (): Promise<ParticipantActivityItem[]> => {
+      const apps = applications.data ?? [];
+      const subs = submissions.data ?? [];
+      return [
+        ...apps.map<ParticipantActivityItem>(application => ({ kind: 'application', data: application })),
+        ...subs.map<ParticipantActivityItem>(submission => ({ kind: 'submission', data: submission })),
+      ];
+    },
+    enabled: !!bountyId && applications.isFetched && submissions.isFetched,
+  });
+}
diff --git a/tests/hooks/bounties/use-bounty-escrow.test.ts b/tests/hooks/bounties/use-bounty-escrow.test.ts
new file mode 100644
index 000000000..dfb6b4d72
--- /dev/null
+++ b/tests/hooks/bounties/use-bounty-escrow.test.ts
@@ -0,0 +1,70 @@
+import { renderHook, waitFor, act } from '@testing-library/react';
+import { QueryClient, QueryClientProvider } from '@tanstack/react-query';
+import { describe, it, expect, vi } from 'vitest';
+import type { ReactNode } from 'react';
+import {
+  useBountiesList,
+  useBounty,
+  useMyBountyApplications,
+  useApplyToBounty,
+  useJoinCompetition,
+  useEditApplication,
+  useWithdrawApplication,
+  useSubmitBounty,
+  useWithdrawSubmission,
+  useMyBountyActivity,
+} from '@/features/bounties/hooks/use-bounty-escrow';
+
+function wrap(hook: () => unknown) {
+  const qc = new QueryClient({ defaultOptions: { queries: { retry: false } } });
+  return renderHook(() => hook(), {
+    wrapper: ({ children }: { children: ReactNode }) => (
+      <QueryClientProvider client={qc}>{children}</QueryClientProvider>
+    ),
+  });
+}
+
+describe('use-bounty-escrow', () => {
+  it('useBountiesList fetches bounties', async () => {
+    global.fetch = vi.fn(() =>
+      Promise.resolve({
+        ok: true,
+        status: 200,
+        json: () => Promise.resolve({ bounties: [{ id: 'b1', title: 'T', description: '', reward: '1', status: 'open', createdAt: '2026-01-01T00:00:00Z' }], pagination: { total: 1 } }),
+      } as Response),
+    );
+
+    const { result } = wrap(() => useBountiesList());
+    await waitFor(() => result.current.isSuccess);
+    expect(result.current.data?.bounties).toHaveLength(1);
+  });
+
+  it('useSubmitBounty forwards payload to escrow op', async () => {
+    const captured: Array<{ url?: string; body?: BodyInit | null }> = [];
+    global.fetch = vi.fn((url: string, init?: RequestInit) => {
+      captured.push({ url, body: init?.body });
+      return Promise.resolve({
+        ok: true,
+        status: 200,
+        json: () => Promise.resolve({ submission: { id: 'sub_1', status: 'ok' } }),
+      } as Response);
+    });
+
+    const { result } = wrap(() => useSubmitBounty('bounty-1'));
+
+    await act(async () => {
+      await result.current.mutateAsync({ description: 'my submission payload' });
+    });
+
+    expect(
+      captured.some(
+        (c): c is { url: string; body?: BodyInit | null } =>
+          typeof c.url === 'string' &&
+          c.url.includes('/api/escrow/ops') &&
+          typeof c.body === 'string' &&
+          c.body.includes('bounty-1') &&
+          c.body.includes('my submission payload'),
+      ),
+    ).toBe(true);
+  });
+});