diff --git a/hooks/use-application-contracts.ts b/hooks/use-application-contracts.ts
new file mode 100644
index 00000000..524fc95f
--- /dev/null
+++ b/hooks/use-application-contracts.ts
@@ -0,0 +1,61 @@
+"use client";
+
+export type ApplicationContractClient = {
+  apply: (params: {
+    applicant: string;
+    bountyId: bigint;
+    proposal: string;
+  }) => Promise<{ txHash: string }>;
+  selectApplicant: (params: {
+    creator: string;
+    bountyId: bigint;
+    applicant: string;
+  }) => Promise<{ txHash: string }>;
+  submitWork: (params: {
+    contributor: string;
+    bountyId: bigint;
+    workCid: string;
+  }) => Promise<{ txHash: string }>;
+  approveSubmission: (params: {
+    creator: string;
+    bountyId: bigint;
+    points: number;
+  }) => Promise<{ txHash: string }>;
+  applyForSlot: (params: {
+    applicant: string;
+    bountyId: bigint;
+  }) => Promise<{ txHash: string }>;
+};
+
+export type ApplicationErrorCode =
+  | "missing_contract_bindings"
+  | "already_applied"
+  | "tx_failed";
+
+export class ApplicationError extends Error {
+  code: ApplicationErrorCode;
+  constructor(code: ApplicationErrorCode, message: string) {
+    super(message);
+    this.code = code;
+  }
+}
+
+export function toBountyIdBigInt(id: string): bigint {
+  if (/^\d+$/.test(id)) return BigInt(id);
+  const hex = id.replace(/-/g, "");
+  if (/^[0-9a-f]+$/i.test(hex)) return BigInt(`0x${hex}`);
+  throw new ApplicationError("tx_failed", `Invalid bounty ID: "${id}"`);
+}
+
+export function resolveApplicationClient(): ApplicationContractClient {
+  const client = (
+    globalThis as { __applicationContracts?: ApplicationContractClient }
+  ).__applicationContracts;
+  if (!client) {
+    throw new ApplicationError(
+      "missing_contract_bindings",
+      "Application contract bindings unavailable. Ensure bindings are loaded.",
+    );
+  }
+  return client;
+}
diff --git a/hooks/use-application-mutations.ts b/hooks/use-application-mutations.ts
new file mode 100644
index 00000000..ffe3c743
--- /dev/null
+++ b/hooks/use-application-mutations.ts
@@ -0,0 +1,256 @@
+"use client";
+
+import { useMutation, useQueryClient } from "@tanstack/react-query";
+import { bountyKeys } from "@/lib/query/query-keys";
+import { type BountyQuery } from "@/lib/graphql/generated";
+import {
+  resolveApplicationClient,
+  toBountyIdBigInt,
+} from "./use-application-contracts";
+
+type DeclinedApplicationRecord = {
+  id?: string;
+  bountyId?: string;
+  applicantAddress?: string;
+  status?: string;
+  declineReason?: string;
+  declinedAt?: string;
+};
+
+type BountyWithApplications = BountyQuery & {
+  bounty?: BountyQuery["bounty"] & {
+    applications?: DeclinedApplicationRecord[];
+  };
+};
+
+export function useApplyToBounty() {
+  const qc = useQueryClient();
+
+  return useMutation({
+    mutationFn: async ({
+      bountyId,
+      applicantAddress,
+      proposal,
+    }: {
+      bountyId: string;
+      applicantAddress: string;
+      proposal: string;
+    }) => {
+      const client = resolveApplicationClient();
+      return client.apply({
+        applicant: applicantAddress,
+        bountyId: toBountyIdBigInt(bountyId),
+        proposal,
+      });
+    },
+    onSettled: (_r, _e, v) => {
+      qc.invalidateQueries({ queryKey: bountyKeys.detail(v.bountyId) });
+    },
+  });
+}
+
+export function useSelectApplicant() {
+  const qc = useQueryClient();
+
+  return useMutation({
+    mutationFn: async ({
+      bountyId,
+      creatorAddress,
+      applicantAddress,
+    }: {
+      bountyId: string;
+      creatorAddress: string;
+      applicantAddress: string;
+    }) => {
+      const client = resolveApplicationClient();
+      return client.selectApplicant({
+        creator: creatorAddress,
+        bountyId: toBountyIdBigInt(bountyId),
+        applicant: applicantAddress,
+      });
+    },
+    onMutate: async ({ bountyId }) => {
+      await qc.cancelQueries({ queryKey: bountyKeys.detail(bountyId) });
+      const prev = qc.getQueryData<BountyQuery>(bountyKeys.detail(bountyId));
+      if (prev?.bounty) {
+        qc.setQueryData<BountyQuery>(bountyKeys.detail(bountyId), {
+          ...prev,
+          bounty: {
+            ...prev.bounty,
+            status: "IN_PROGRESS",
+            updatedAt: new Date().toISOString(),
+          },
+        });
+      }
+      return { prev, bountyId };
+    },
+    onError: (_e, _v, ctx) => {
+      if (ctx?.prev) qc.setQueryData(bountyKeys.detail(ctx.bountyId), ctx.prev);
+    },
+    onSettled: (_r, _e, v) => {
+      qc.invalidateQueries({ queryKey: bountyKeys.detail(v.bountyId) });
+      qc.invalidateQueries({ queryKey: bountyKeys.lists() });
+    },
+  });
+}
+
+export function useDeclineApplicant() {
+  const qc = useQueryClient();
+
+  return useMutation({
+    mutationFn: async ({
+      bountyId,
+      applicantAddress,
+      reason,
+    }: {
+      bountyId: string;
+      applicantAddress: string;
+      reason?: string;
+    }) => {
+      return {
+        bountyId,
+        applicantAddress,
+        reason: reason?.trim() || undefined,
+        declinedAt: new Date().toISOString(),
+      };
+    },
+
+    onMutate: async ({ bountyId, applicantAddress, reason }) => {
+      await qc.cancelQueries({ queryKey: bountyKeys.detail(bountyId) });
+
+      const prev = qc.getQueryData<BountyWithApplications>(
+        bountyKeys.detail(bountyId),
+      );
+
+      if (prev?.bounty?.applications) {
+        const declinedAt = new Date().toISOString();
+
+        qc.setQueryData<BountyWithApplications>(bountyKeys.detail(bountyId), {
+          ...prev,
+          bounty: {
+            ...prev.bounty,
+            applications: prev.bounty.applications
+              .map((application) =>
+                application.applicantAddress === applicantAddress
+                  ? {
+                      ...application,
+                      status: "DECLINED",
+                      declineReason: reason?.trim() || undefined,
+                      declinedAt,
+                    }
+                  : application,
+              )
+              .filter(
+                (application) =>
+                  application.applicantAddress !== applicantAddress,
+              ),
+            updatedAt: declinedAt,
+          },
+        });
+      }
+
+      return { prev, bountyId };
+    },
+
+    onError: (_error, _variables, context) => {
+      if (context?.prev) {
+        qc.setQueryData(bountyKeys.detail(context.bountyId), context.prev);
+      }
+    },
+
+    onSettled: (_result, _error, variables) => {
+      qc.invalidateQueries({ queryKey: bountyKeys.detail(variables.bountyId) });
+      qc.invalidateQueries({ queryKey: bountyKeys.lists() });
+    },
+  });
+}
+
+export function useSubmitApplicationWork() {
+  const qc = useQueryClient();
+
+  return useMutation({
+    mutationFn: async ({
+      bountyId,
+      contributorAddress,
+      workCid,
+    }: {
+      bountyId: string;
+      contributorAddress: string;
+      workCid: string;
+    }) => {
+      const client = resolveApplicationClient();
+      return client.submitWork({
+        contributor: contributorAddress,
+        bountyId: toBountyIdBigInt(bountyId),
+        workCid,
+      });
+    },
+    onMutate: async ({ bountyId }) => {
+      await qc.cancelQueries({ queryKey: bountyKeys.detail(bountyId) });
+      const prev = qc.getQueryData<BountyQuery>(bountyKeys.detail(bountyId));
+      if (prev?.bounty) {
+        qc.setQueryData<BountyQuery>(bountyKeys.detail(bountyId), {
+          ...prev,
+          bounty: {
+            ...prev.bounty,
+            status: "UNDER_REVIEW",
+            updatedAt: new Date().toISOString(),
+          },
+        });
+      }
+      return { prev, bountyId };
+    },
+    onError: (_e, _v, ctx) => {
+      if (ctx?.prev) qc.setQueryData(bountyKeys.detail(ctx.bountyId), ctx.prev);
+    },
+    onSettled: (_r, _e, v) => {
+      qc.invalidateQueries({ queryKey: bountyKeys.detail(v.bountyId) });
+      qc.invalidateQueries({ queryKey: bountyKeys.lists() });
+    },
+  });
+}
+
+export function useApproveApplicationSubmission() {
+  const qc = useQueryClient();
+
+  return useMutation({
+    mutationFn: async ({
+      bountyId,
+      creatorAddress,
+      points,
+    }: {
+      bountyId: string;
+      creatorAddress: string;
+      points: number;
+    }) => {
+      const client = resolveApplicationClient();
+      return client.approveSubmission({
+        creator: creatorAddress,
+        bountyId: toBountyIdBigInt(bountyId),
+        points,
+      });
+    },
+    onMutate: async ({ bountyId }) => {
+      await qc.cancelQueries({ queryKey: bountyKeys.detail(bountyId) });
+      const prev = qc.getQueryData<BountyQuery>(bountyKeys.detail(bountyId));
+      if (prev?.bounty) {
+        qc.setQueryData<BountyQuery>(bountyKeys.detail(bountyId), {
+          ...prev,
+          bounty: {
+            ...prev.bounty,
+            status: "COMPLETED",
+            updatedAt: new Date().toISOString(),
+          },
+        });
+      }
+      return { prev, bountyId };
+    },
+    onError: (_e, _v, ctx) => {
+      if (ctx?.prev) qc.setQueryData(bountyKeys.detail(ctx.bountyId), ctx.prev);
+    },
+    onSettled: (_r, _e, v) => {
+      qc.invalidateQueries({ queryKey: bountyKeys.detail(v.bountyId) });
+      qc.invalidateQueries({ queryKey: bountyKeys.lists() });
+    },
+  });
+}
diff --git a/hooks/use-application-review-mutations.ts b/hooks/use-application-review-mutations.ts
new file mode 100644
index 00000000..cda6ac8b
--- /dev/null
+++ b/hooks/use-application-review-mutations.ts
@@ -0,0 +1,67 @@
+"use client";
+
+import { useMutation, useQueryClient } from "@tanstack/react-query";
+import { bountyKeys } from "@/lib/query/query-keys";
+import { fetcher } from "@/lib/graphql/client";
+import {
+  ReviewSubmissionDocument,
+  type BountyQuery,
+  type ReviewSubmissionMutation,
+  type ReviewSubmissionMutationVariables,
+} from "@/lib/graphql/generated";
+
+type RequestRevisionsVars = {
+  bountyId: string;
+  submissionId: string;
+  feedback: string;
+};
+
+type RequestRevisionsCtx = {
+  prev: BountyQuery | undefined;
+  bountyId: string;
+};
+
+export function useRequestRevisions() {
+  const qc = useQueryClient();
+
+  return useMutation<
+    ReviewSubmissionMutation,
+    Error,
+    RequestRevisionsVars,
+    RequestRevisionsCtx
+  >({
+    mutationFn: ({ submissionId, feedback }) =>
+      fetcher<ReviewSubmissionMutation, ReviewSubmissionMutationVariables>(
+        ReviewSubmissionDocument,
+        {
+          input: {
+            submissionId,
+            status: "REVISION_REQUESTED",
+            reviewComments: feedback,
+          },
+        },
+      )(),
+    onMutate: async ({ bountyId }) => {
+      await qc.cancelQueries({ queryKey: bountyKeys.detail(bountyId) });
+      const prev = qc.getQueryData<BountyQuery>(bountyKeys.detail(bountyId));
+      if (prev?.bounty) {
+        qc.setQueryData<BountyQuery>(bountyKeys.detail(bountyId), {
+          ...prev,
+          bounty: {
+            ...prev.bounty,
+            status: "UNDER_REVIEW",
+            updatedAt: new Date().toISOString(),
+          },
+        });
+      }
+      return { prev, bountyId };
+    },
+    onError: (_e, _v, ctx) => {
+      if (ctx?.prev) qc.setQueryData(bountyKeys.detail(ctx.bountyId), ctx.prev);
+    },
+    onSettled: (_r, _e, v) => {
+      qc.invalidateQueries({ queryKey: bountyKeys.detail(v.bountyId) });
+      qc.invalidateQueries({ queryKey: bountyKeys.lists() });
+    },
+  });
+}
diff --git a/hooks/use-bounty-application.ts b/hooks/use-bounty-application.ts
index 20601b2c..953b4bd6 100644
--- a/hooks/use-bounty-application.ts
+++ b/hooks/use-bounty-application.ts
@@ -1,752 +1,7 @@
 "use client";
 
-import { useMutation, useQueryClient } from "@tanstack/react-query";
-import { authClient } from "@/lib/auth-client";
-import { bountyKeys } from "@/lib/query/query-keys";
-import { MOCK_MODEL4_MILESTONES } from "@/lib/mock/model4";
-import { fetcher } from "@/lib/graphql/client";
-import {
-  ReviewSubmissionDocument,
-  type BountyQuery,
-  type DisputeReasonEnum,
-  type ReviewSubmissionMutation,
-  type ReviewSubmissionMutationVariables,
-} from "@/lib/graphql/generated";
-import type { ContributorProgress, Bounty, Milestone } from "@/types/bounty";
-import { escrowKeys } from "./use-escrow";
-import { EscrowService } from "@/lib/services/escrow";
-import type { EscrowPool } from "@/types/escrow";
-import { post } from "@/lib/api/client";
-
-export type ExtendedBountyQuery = Omit<BountyQuery, "bounty"> & {
-  bounty?: BountyQuery["bounty"] & Partial<Bounty>;
-};
-
-export const delay = (ms: number) =>
-  new Promise((resolve) => setTimeout(resolve, ms));
-
-// ---------------------------------------------------------------------------
-// Contract client shape (resolved from globalThis.__applicationContracts)
-// ---------------------------------------------------------------------------
-
-type ApplicationContractClient = {
-  apply: (params: {
-    applicant: string;
-    bountyId: bigint;
-    proposal: string;
-  }) => Promise<{ txHash: string }>;
-  selectApplicant: (params: {
-    creator: string;
-    bountyId: bigint;
-    applicant: string;
-  }) => Promise<{ txHash: string }>;
-  submitWork: (params: {
-    contributor: string;
-    bountyId: bigint;
-    workCid: string;
-  }) => Promise<{ txHash: string }>;
-  approveSubmission: (params: {
-    creator: string;
-    bountyId: bigint;
-    points: number;
-  }) => Promise<{ txHash: string }>;
-  applyForSlot: (params: {
-    applicant: string;
-    bountyId: bigint;
-  }) => Promise<{ txHash: string }>;
-};
-
-// ---------------------------------------------------------------------------
-// Error
-// ---------------------------------------------------------------------------
-
-export type ApplicationErrorCode =
-  | "missing_contract_bindings"
-  | "already_applied"
-  | "tx_failed";
-
-export class ApplicationError extends Error {
-  code: ApplicationErrorCode;
-  constructor(code: ApplicationErrorCode, message: string) {
-    super(message);
-    this.code = code;
-  }
-}
-
-// ---------------------------------------------------------------------------
-// Helpers
-// ---------------------------------------------------------------------------
-
-function toBountyIdBigInt(id: string): bigint {
-  if (/^\d+$/.test(id)) return BigInt(id);
-  const hex = id.replace(/-/g, "");
-  if (/^[0-9a-f]+$/i.test(hex)) return BigInt(`0x${hex}`);
-  throw new ApplicationError("tx_failed", `Invalid bounty ID: "${id}"`);
-}
-
-function resolveApplicationClient(): ApplicationContractClient {
-  const client = (
-    globalThis as { __applicationContracts?: ApplicationContractClient }
-  ).__applicationContracts;
-  if (!client) {
-    throw new ApplicationError(
-      "missing_contract_bindings",
-      "Application contract bindings unavailable. Ensure bindings are loaded.",
-    );
-  }
-  return client;
-}
-
-// ---------------------------------------------------------------------------
-// Hook: apply (BountyRegistry.apply)
-// ---------------------------------------------------------------------------
-
-export function useApplyToBounty() {
-  const qc = useQueryClient();
-
-  return useMutation({
-    mutationFn: async ({
-      bountyId,
-      applicantAddress,
-      proposal,
-    }: {
-      bountyId: string;
-      applicantAddress: string;
-      proposal: string;
-    }) => {
-      const client = resolveApplicationClient();
-      return client.apply({
-        applicant: applicantAddress,
-        bountyId: toBountyIdBigInt(bountyId),
-        proposal,
-      });
-    },
-    onSettled: (_r, _e, v) => {
-      qc.invalidateQueries({ queryKey: bountyKeys.detail(v.bountyId) });
-    },
-  });
-}
-
-// ---------------------------------------------------------------------------
-// Hook: select applicant (BountyRegistry.select_applicant)
-// ---------------------------------------------------------------------------
-
-export function useSelectApplicant() {
-  const qc = useQueryClient();
-
-  return useMutation({
-    mutationFn: async ({
-      bountyId,
-      creatorAddress,
-      applicantAddress,
-    }: {
-      bountyId: string;
-      creatorAddress: string;
-      applicantAddress: string;
-    }) => {
-      const client = resolveApplicationClient();
-      return client.selectApplicant({
-        creator: creatorAddress,
-        bountyId: toBountyIdBigInt(bountyId),
-        applicant: applicantAddress,
-      });
-    },
-    onMutate: async ({ bountyId }) => {
-      await qc.cancelQueries({ queryKey: bountyKeys.detail(bountyId) });
-      const prev = qc.getQueryData<BountyQuery>(bountyKeys.detail(bountyId));
-      if (prev?.bounty) {
-        qc.setQueryData<BountyQuery>(bountyKeys.detail(bountyId), {
-          ...prev,
-          bounty: {
-            ...prev.bounty,
-            status: "IN_PROGRESS",
-            updatedAt: new Date().toISOString(),
-          },
-        });
-      }
-      return { prev, bountyId };
-    },
-    onError: (_e, _v, ctx) => {
-      if (ctx?.prev) qc.setQueryData(bountyKeys.detail(ctx.bountyId), ctx.prev);
-    },
-    onSettled: (_r, _e, v) => {
-      qc.invalidateQueries({ queryKey: bountyKeys.detail(v.bountyId) });
-      qc.invalidateQueries({ queryKey: bountyKeys.lists() });
-    },
-  });
-}
-// ---------------------------------------------------------------------------
-// Hook: decline applicant
-// ---------------------------------------------------------------------------
-
-type DeclinedApplicationRecord = {
-  id?: string;
-  bountyId?: string;
-  applicantAddress?: string;
-  status?: string;
-  declineReason?: string;
-  declinedAt?: string;
-};
-
-type BountyWithApplications = BountyQuery & {
-  bounty?: BountyQuery["bounty"] & {
-    applications?: DeclinedApplicationRecord[];
-  };
-};
-
-export function useDeclineApplicant() {
-  const qc = useQueryClient();
-
-  return useMutation({
-    mutationFn: async ({
-      bountyId,
-      applicantAddress,
-      reason,
-    }: {
-      bountyId: string;
-      applicantAddress: string;
-      reason?: string;
-    }) => {
-      return {
-        bountyId,
-        applicantAddress,
-        reason: reason?.trim() || undefined,
-        declinedAt: new Date().toISOString(),
-      };
-    },
-
-    onMutate: async ({ bountyId, applicantAddress, reason }) => {
-      await qc.cancelQueries({ queryKey: bountyKeys.detail(bountyId) });
-
-      const prev = qc.getQueryData<BountyWithApplications>(
-        bountyKeys.detail(bountyId),
-      );
-
-      if (prev?.bounty?.applications) {
-        const declinedAt = new Date().toISOString();
-
-        qc.setQueryData<BountyWithApplications>(bountyKeys.detail(bountyId), {
-          ...prev,
-          bounty: {
-            ...prev.bounty,
-            applications: prev.bounty.applications
-              .map((application) =>
-                application.applicantAddress === applicantAddress
-                  ? {
-                      ...application,
-                      status: "DECLINED",
-                      declineReason: reason?.trim() || undefined,
-                      declinedAt,
-                    }
-                  : application,
-              )
-              .filter(
-                (application) =>
-                  application.applicantAddress !== applicantAddress,
-              ),
-            updatedAt: declinedAt,
-          },
-        });
-      }
-
-      return { prev, bountyId };
-    },
-
-    onError: (_error, _variables, context) => {
-      if (context?.prev) {
-        qc.setQueryData(bountyKeys.detail(context.bountyId), context.prev);
-      }
-    },
-
-    onSettled: (_result, _error, variables) => {
-      qc.invalidateQueries({ queryKey: bountyKeys.detail(variables.bountyId) });
-      qc.invalidateQueries({ queryKey: bountyKeys.lists() });
-    },
-  });
-}
-
-// ---------------------------------------------------------------------------
-// Hook: submit work (BountyRegistry.submit_work)
-// ---------------------------------------------------------------------------
-
-export function useSubmitApplicationWork() {
-  const qc = useQueryClient();
-
-  return useMutation({
-    mutationFn: async ({
-      bountyId,
-      contributorAddress,
-      workCid,
-    }: {
-      bountyId: string;
-      contributorAddress: string;
-      workCid: string;
-    }) => {
-      const client = resolveApplicationClient();
-      return client.submitWork({
-        contributor: contributorAddress,
-        bountyId: toBountyIdBigInt(bountyId),
-        workCid,
-      });
-    },
-    onMutate: async ({ bountyId }) => {
-      await qc.cancelQueries({ queryKey: bountyKeys.detail(bountyId) });
-      const prev = qc.getQueryData<BountyQuery>(bountyKeys.detail(bountyId));
-      if (prev?.bounty) {
-        qc.setQueryData<BountyQuery>(bountyKeys.detail(bountyId), {
-          ...prev,
-          bounty: {
-            ...prev.bounty,
-            status: "UNDER_REVIEW",
-            updatedAt: new Date().toISOString(),
-          },
-        });
-      }
-      return { prev, bountyId };
-    },
-    onError: (_e, _v, ctx) => {
-      if (ctx?.prev) qc.setQueryData(bountyKeys.detail(ctx.bountyId), ctx.prev);
-    },
-    onSettled: (_r, _e, v) => {
-      qc.invalidateQueries({ queryKey: bountyKeys.detail(v.bountyId) });
-      qc.invalidateQueries({ queryKey: bountyKeys.lists() });
-    },
-  });
-}
-
-// ---------------------------------------------------------------------------
-// Hook: approve submission (BountyRegistry.approve_submission)
-// ---------------------------------------------------------------------------
-
-export function useApproveApplicationSubmission() {
-  const qc = useQueryClient();
-
-  return useMutation({
-    mutationFn: async ({
-      bountyId,
-      creatorAddress,
-      points,
-    }: {
-      bountyId: string;
-      creatorAddress: string;
-      points: number;
-    }) => {
-      const client = resolveApplicationClient();
-      return client.approveSubmission({
-        creator: creatorAddress,
-        bountyId: toBountyIdBigInt(bountyId),
-        points,
-      });
-    },
-    onMutate: async ({ bountyId }) => {
-      await qc.cancelQueries({ queryKey: bountyKeys.detail(bountyId) });
-      const prev = qc.getQueryData<BountyQuery>(bountyKeys.detail(bountyId));
-      if (prev?.bounty) {
-        qc.setQueryData<BountyQuery>(bountyKeys.detail(bountyId), {
-          ...prev,
-          bounty: {
-            ...prev.bounty,
-            status: "COMPLETED",
-            updatedAt: new Date().toISOString(),
-          },
-        });
-      }
-      return { prev, bountyId };
-    },
-    onError: (_e, _v, ctx) => {
-      if (ctx?.prev) qc.setQueryData(bountyKeys.detail(ctx.bountyId), ctx.prev);
-    },
-    onSettled: (_r, _e, v) => {
-      qc.invalidateQueries({ queryKey: bountyKeys.detail(v.bountyId) });
-      qc.invalidateQueries({ queryKey: bountyKeys.lists() });
-    },
-  });
-}
-
-// ---------------------------------------------------------------------------
-// Hook: request revisions (reviewSubmission with status REVISION_REQUESTED)
-// ---------------------------------------------------------------------------
-
-type RequestRevisionsVars = {
-  bountyId: string;
-  submissionId: string;
-  feedback: string;
-};
-
-type RequestRevisionsCtx = {
-  prev: BountyQuery | undefined;
-  bountyId: string;
-};
-
-export function useRequestRevisions() {
-  const qc = useQueryClient();
-
-  return useMutation<
-    ReviewSubmissionMutation,
-    Error,
-    RequestRevisionsVars,
-    RequestRevisionsCtx
-  >({
-    mutationFn: ({ submissionId, feedback }) =>
-      fetcher<ReviewSubmissionMutation, ReviewSubmissionMutationVariables>(
-        ReviewSubmissionDocument,
-        {
-          input: {
-            submissionId,
-            status: "REVISION_REQUESTED",
-            reviewComments: feedback,
-          },
-        },
-      )(),
-    onMutate: async ({ bountyId }) => {
-      await qc.cancelQueries({ queryKey: bountyKeys.detail(bountyId) });
-      const prev = qc.getQueryData<BountyQuery>(bountyKeys.detail(bountyId));
-      if (prev?.bounty) {
-        qc.setQueryData<BountyQuery>(bountyKeys.detail(bountyId), {
-          ...prev,
-          bounty: {
-            ...prev.bounty,
-            status: "UNDER_REVIEW",
-            updatedAt: new Date().toISOString(),
-          },
-        });
-      }
-      return { prev, bountyId };
-    },
-    onError: (_e, _v, ctx) => {
-      if (ctx?.prev) qc.setQueryData(bountyKeys.detail(ctx.bountyId), ctx.prev);
-    },
-    onSettled: (_r, _e, v) => {
-      qc.invalidateQueries({ queryKey: bountyKeys.detail(v.bountyId) });
-      qc.invalidateQueries({ queryKey: bountyKeys.lists() });
-    },
-  });
-}
-
-// ---------------------------------------------------------------------------
-// Hook: apply for slot (BountyRegistry.apply_for_slot)
-// ---------------------------------------------------------------------------
-
-export function useApplyForSlot() {
-  const qc = useQueryClient();
-  const { data: session } = authClient.useSession();
-
-  return useMutation({
-    mutationFn: async ({
-      bountyId,
-      applicantAddress,
-    }: {
-      bountyId: string;
-      applicantAddress: string;
-    }) => {
-      const client = resolveApplicationClient();
-      return client.applyForSlot({
-        applicant: applicantAddress,
-        bountyId: toBountyIdBigInt(bountyId),
-      });
-    },
-    onMutate: async ({ bountyId }) => {
-      await qc.cancelQueries({ queryKey: bountyKeys.detail(bountyId) });
-      const prev = qc.getQueryData<BountyQuery & { bounty?: Partial<Bounty> }>(
-        bountyKeys.detail(bountyId),
-      );
-      if (prev?.bounty) {
-        const milestones = prev.bounty.milestones ?? MOCK_MODEL4_MILESTONES;
-        const firstMilestoneId = milestones[0]?.id ?? "m1";
-        const newProgress: ContributorProgress = {
-          userId: session?.user?.id ?? "unknown-user",
-          userName: session?.user?.name ?? "Contributor",
-          userAvatarUrl:
-            session?.user?.image ?? "https://github.com/shadcn.png",
-          currentMilestoneId: firstMilestoneId,
-        };
-        const prevProgress = prev.bounty.contributorProgress ?? [];
-        const updatedProgress = [...prevProgress, newProgress];
-        const occupied = (prev.bounty.totalSlotsOccupied ?? 0) + 1;
-
-        qc.setQueryData<BountyQuery & { bounty?: Partial<Bounty> }>(
-          bountyKeys.detail(bountyId),
-          {
-            ...prev,
-            bounty: {
-              ...prev.bounty,
-              totalSlotsOccupied: occupied,
-              contributorProgress: updatedProgress,
-            },
-          },
-        );
-      }
-      return { prev, bountyId };
-    },
-    onError: (_e, _v, ctx) => {
-      if (ctx?.prev) qc.setQueryData(bountyKeys.detail(ctx.bountyId), ctx.prev);
-    },
-    onSettled: (_r, _e, variables) => {
-      if (variables?.bountyId) {
-        qc.invalidateQueries({
-          queryKey: bountyKeys.detail(variables.bountyId),
-        });
-      }
-      qc.invalidateQueries({ queryKey: bountyKeys.lists() });
-    },
-  });
-}
-// Static memory storage for messages
-const recordedMessages: Record<
-  string,
-  Array<{ contributorId: string; message: string; timestamp: string }>
-> = {};
-
-export function useReleasePayment(bountyId: string) {
-  const queryClient = useQueryClient();
-
-  return useMutation({
-    mutationFn: async ({
-      contributorId,
-      milestoneId,
-    }: {
-      contributorId: string;
-      milestoneId: string;
-    }) => {
-      // Calculate proportional milestone payment amount
-      const previous = queryClient.getQueryData<ExtendedBountyQuery>(
-        bountyKeys.detail(bountyId),
-      );
-      const totalAmount = previous?.bounty?.rewardAmount ?? 100;
-      const milestonesCount = previous?.bounty?.milestones?.length ?? 1;
-      const amountToRelease = totalAmount / milestonesCount;
-
-      // Persist mock escrow data update
-      await EscrowService.releasePayment(bountyId, amountToRelease);
-      return { contributorId, milestoneId, amountToRelease };
-    },
-    onMutate: async () => {
-      await queryClient.cancelQueries({ queryKey: escrowKeys.pool(bountyId) });
-      const prevPool = queryClient.getQueryData<EscrowPool>(
-        escrowKeys.pool(bountyId),
-      );
-
-      const prevBounty = queryClient.getQueryData<ExtendedBountyQuery>(
-        bountyKeys.detail(bountyId),
-      );
-      const totalAmount = prevBounty?.bounty?.rewardAmount ?? 100;
-      const milestonesCount = prevBounty?.bounty?.milestones?.length ?? 1;
-      const amountToRelease = totalAmount / milestonesCount;
-
-      if (prevPool) {
-        const newReleased = Math.min(
-          prevPool.totalAmount,
-          prevPool.releasedAmount + amountToRelease,
-        );
-        const status =
-          newReleased >= prevPool.totalAmount
-            ? "Fully Released"
-            : "Partially Released";
-        queryClient.setQueryData(escrowKeys.pool(bountyId), {
-          ...prevPool,
-          releasedAmount: newReleased,
-          status,
-        });
-      }
-      return { prevPool };
-    },
-    onError: (_err, _vars, context) => {
-      if (context?.prevPool) {
-        queryClient.setQueryData(escrowKeys.pool(bountyId), context.prevPool);
-      }
-    },
-    onSuccess: () => {
-      // Refresh bounty details and escrow pool data
-      queryClient.invalidateQueries({ queryKey: bountyKeys.detail(bountyId) });
-      queryClient.invalidateQueries({ queryKey: escrowKeys.pool(bountyId) });
-    },
-  });
-}
-
-export function useAdvanceContributor(bountyId: string) {
-  const queryClient = useQueryClient();
-
-  return useMutation({
-    mutationFn: async ({ contributorId }: { contributorId: string }) => {
-      await delay(1000);
-      return { contributorId };
-    },
-    onMutate: async ({ contributorId }) => {
-      await queryClient.cancelQueries({
-        queryKey: bountyKeys.detail(bountyId),
-      });
-      const previous = queryClient.getQueryData<ExtendedBountyQuery>(
-        bountyKeys.detail(bountyId),
-      );
-
-      if (previous?.bounty) {
-        const contributorProgress: ContributorProgress[] =
-          previous.bounty.contributorProgress || [];
-        const contributorIndex = contributorProgress.findIndex(
-          (c) => c.userId === contributorId,
-        );
-
-        if (contributorIndex >= 0) {
-          const milestones: Milestone[] = previous.bounty.milestones || [];
-          const currentMilestoneId =
-            contributorProgress[contributorIndex].currentMilestoneId;
-          const milestoneIndex = milestones.findIndex(
-            (m) => m.id === currentMilestoneId,
-          );
-
-          if (milestoneIndex >= 0 && milestoneIndex < milestones.length - 1) {
-            const nextMilestone = milestones[milestoneIndex + 1];
-            const newProgress = [...contributorProgress];
-            newProgress[contributorIndex] = {
-              ...newProgress[contributorIndex],
-              currentMilestoneId: nextMilestone.id,
-            };
-
-            queryClient.setQueryData<ExtendedBountyQuery>(
-              bountyKeys.detail(bountyId),
-              {
-                ...previous,
-                bounty: {
-                  ...previous.bounty,
-                  contributorProgress: newProgress,
-                },
-              },
-            );
-          }
-        }
-      }
-      return { previous };
-    },
-    onError: (_err, _vars, context) => {
-      if (context?.previous) {
-        queryClient.setQueryData(bountyKeys.detail(bountyId), context.previous);
-      }
-    },
-    onSuccess: () => {
-      queryClient.invalidateQueries({ queryKey: bountyKeys.detail(bountyId) });
-    },
-  });
-}
-
-export function useRemoveContributor(bountyId: string) {
-  const queryClient = useQueryClient();
-
-  return useMutation({
-    mutationFn: async ({ contributorId }: { contributorId: string }) => {
-      await delay(1000);
-      return { contributorId };
-    },
-    onMutate: async ({ contributorId }) => {
-      await queryClient.cancelQueries({
-        queryKey: bountyKeys.detail(bountyId),
-      });
-      const previous = queryClient.getQueryData<ExtendedBountyQuery>(
-        bountyKeys.detail(bountyId),
-      );
-
-      if (previous?.bounty) {
-        const contributorProgress: ContributorProgress[] =
-          previous.bounty.contributorProgress || [];
-
-        // Decrement total slots occupied by 1
-        const occupied = Math.max(
-          0,
-          (previous.bounty.totalSlotsOccupied ?? 1) - 1,
-        );
-
-        queryClient.setQueryData<ExtendedBountyQuery>(
-          bountyKeys.detail(bountyId),
-          {
-            ...previous,
-            bounty: {
-              ...previous.bounty,
-              totalSlotsOccupied: occupied,
-              contributorProgress: contributorProgress.filter(
-                (c) => c.userId !== contributorId,
-              ),
-            },
-          },
-        );
-      }
-      return { previous };
-    },
-    onError: (_err, _vars, context) => {
-      if (context?.previous) {
-        queryClient.setQueryData(bountyKeys.detail(bountyId), context.previous);
-      }
-    },
-    onSuccess: () => {
-      queryClient.invalidateQueries({ queryKey: bountyKeys.detail(bountyId) });
-    },
-  });
-}
-
-export function useSendMessage(bountyId: string) {
-  return useMutation({
-    mutationFn: async ({
-      contributorId,
-      message,
-    }: {
-      contributorId: string;
-      message: string;
-    }) => {
-      await delay(1000);
-
-      // Store in static memory for real message logging/recording
-      if (!recordedMessages[bountyId]) {
-        recordedMessages[bountyId] = [];
-      }
-      recordedMessages[bountyId].push({
-        contributorId,
-        message,
-        timestamp: new Date().toISOString(),
-      });
-
-      return { contributorId, message };
-    },
-  });
-}
-
-// ---------------------------------------------------------------------------
-// Hook: raise dispute
-// ---------------------------------------------------------------------------
-
-export interface RaiseDisputeInput {
-  bountyId: string;
-  reason: DisputeReasonEnum;
-  description: string;
-}
-
-export interface RaiseDisputeResult {
-  id: string;
-  campaignId: string;
-  reason: string;
-  description: string;
-  status: string;
-  createdAt: string;
-}
-
-/**
- * Submits a new dispute for a bounty via the REST API.
- *
- * On success it returns the created dispute (including its `id`) and
- * invalidates the bounty detail query so the UI reflects the new DISPUTED
- * status immediately.
- */
-export function useRaiseDispute() {
-  const qc = useQueryClient();
-
-  return useMutation<RaiseDisputeResult, Error, RaiseDisputeInput>({
-    mutationFn: async ({ bountyId, reason, description }) => {
-      return post<RaiseDisputeResult>("/api/disputes", {
-        campaignId: bountyId,
-        reason,
-        description,
-      });
-    },
-    onSuccess: (_data, variables) => {
-      qc.invalidateQueries({ queryKey: bountyKeys.detail(variables.bountyId) });
-      qc.invalidateQueries({ queryKey: bountyKeys.lists() });
-    },
-  });
-}
+export * from "./use-application-contracts";
+export * from "./use-application-mutations";
+export * from "./use-application-review-mutations";
+export * from "./use-milestone-mutations";
+export * from "./use-dispute-mutations";
diff --git a/hooks/use-dispute-mutations.ts b/hooks/use-dispute-mutations.ts
new file mode 100644
index 00000000..2d997b0a
--- /dev/null
+++ b/hooks/use-dispute-mutations.ts
@@ -0,0 +1,39 @@
+"use client";
+
+import { useMutation, useQueryClient } from "@tanstack/react-query";
+import { bountyKeys } from "@/lib/query/query-keys";
+import { post } from "@/lib/api/client";
+import type { DisputeReasonEnum } from "@/lib/graphql/generated";
+
+export interface RaiseDisputeInput {
+  bountyId: string;
+  reason: DisputeReasonEnum;
+  description: string;
+}
+
+export interface RaiseDisputeResult {
+  id: string;
+  campaignId: string;
+  reason: string;
+  description: string;
+  status: string;
+  createdAt: string;
+}
+
+export function useRaiseDispute() {
+  const qc = useQueryClient();
+
+  return useMutation<RaiseDisputeResult, Error, RaiseDisputeInput>({
+    mutationFn: async ({ bountyId, reason, description }) => {
+      return post<RaiseDisputeResult>("/api/disputes", {
+        campaignId: bountyId,
+        reason,
+        description,
+      });
+    },
+    onSuccess: (_data, variables) => {
+      qc.invalidateQueries({ queryKey: bountyKeys.detail(variables.bountyId) });
+      qc.invalidateQueries({ queryKey: bountyKeys.lists() });
+    },
+  });
+}
diff --git a/hooks/use-milestone-mutations.ts b/hooks/use-milestone-mutations.ts
new file mode 100644
index 00000000..26d84d95
--- /dev/null
+++ b/hooks/use-milestone-mutations.ts
@@ -0,0 +1,292 @@
+"use client";
+
+import { useMutation, useQueryClient } from "@tanstack/react-query";
+import { authClient } from "@/lib/auth-client";
+import { bountyKeys } from "@/lib/query/query-keys";
+import { MOCK_MODEL4_MILESTONES } from "@/lib/mock/model4";
+import { escrowKeys } from "./use-escrow";
+import { EscrowService } from "@/lib/services/escrow";
+import type { ContributorProgress, Bounty, Milestone } from "@/types/bounty";
+import type { EscrowPool } from "@/types/escrow";
+import {
+  resolveApplicationClient,
+  toBountyIdBigInt,
+} from "./use-application-contracts";
+import type { BountyQuery } from "@/lib/graphql/generated";
+
+const delay = (ms: number) => new Promise((resolve) => setTimeout(resolve, ms));
+
+type ExtendedBountyQuery = Omit<BountyQuery, "bounty"> & {
+  bounty?: BountyQuery["bounty"] & Partial<Bounty>;
+};
+
+const recordedMessages: Record<
+  string,
+  Array<{ contributorId: string; message: string; timestamp: string }>
+> = {};
+
+export function useApplyForSlot() {
+  const qc = useQueryClient();
+  const { data: session } = authClient.useSession();
+
+  return useMutation({
+    mutationFn: async ({
+      bountyId,
+      applicantAddress,
+    }: {
+      bountyId: string;
+      applicantAddress: string;
+    }) => {
+      const client = resolveApplicationClient();
+      return client.applyForSlot({
+        applicant: applicantAddress,
+        bountyId: toBountyIdBigInt(bountyId),
+      });
+    },
+    onMutate: async ({ bountyId }) => {
+      await qc.cancelQueries({ queryKey: bountyKeys.detail(bountyId) });
+      const prev = qc.getQueryData<ExtendedBountyQuery>(
+        bountyKeys.detail(bountyId),
+      );
+      if (prev?.bounty) {
+        const milestones = prev.bounty.milestones ?? MOCK_MODEL4_MILESTONES;
+        const firstMilestoneId = milestones[0]?.id ?? "m1";
+        const newProgress: ContributorProgress = {
+          userId: session?.user?.id ?? "unknown-user",
+          userName: session?.user?.name ?? "Contributor",
+          userAvatarUrl:
+            session?.user?.image ?? "https://github.com/shadcn.png",
+          currentMilestoneId: firstMilestoneId,
+        };
+        const prevProgress = prev.bounty.contributorProgress ?? [];
+        const updatedProgress = [...prevProgress, newProgress];
+        const occupied = (prev.bounty.totalSlotsOccupied ?? 0) + 1;
+
+        qc.setQueryData<ExtendedBountyQuery>(bountyKeys.detail(bountyId), {
+          ...prev,
+          bounty: {
+            ...prev.bounty,
+            totalSlotsOccupied: occupied,
+            contributorProgress: updatedProgress,
+          },
+        });
+      }
+      return { prev, bountyId };
+    },
+    onError: (_e, _v, ctx) => {
+      if (ctx?.prev) qc.setQueryData(bountyKeys.detail(ctx.bountyId), ctx.prev);
+    },
+    onSettled: (_r, _e, variables) => {
+      if (variables?.bountyId) {
+        qc.invalidateQueries({
+          queryKey: bountyKeys.detail(variables.bountyId),
+        });
+      }
+      qc.invalidateQueries({ queryKey: bountyKeys.lists() });
+    },
+  });
+}
+
+export function useReleasePayment(bountyId: string) {
+  const queryClient = useQueryClient();
+
+  return useMutation({
+    mutationFn: async ({
+      contributorId,
+      milestoneId,
+    }: {
+      contributorId: string;
+      milestoneId: string;
+    }) => {
+      const previous = queryClient.getQueryData<ExtendedBountyQuery>(
+        bountyKeys.detail(bountyId),
+      );
+      const totalAmount = previous?.bounty?.rewardAmount ?? 100;
+      const milestonesCount = previous?.bounty?.milestones?.length ?? 1;
+      const amountToRelease = totalAmount / milestonesCount;
+
+      await EscrowService.releasePayment(bountyId, amountToRelease);
+      return { contributorId, milestoneId, amountToRelease };
+    },
+    onMutate: async () => {
+      await queryClient.cancelQueries({ queryKey: escrowKeys.pool(bountyId) });
+      const prevPool = queryClient.getQueryData<EscrowPool>(
+        escrowKeys.pool(bountyId),
+      );
+
+      const prevBounty = queryClient.getQueryData<ExtendedBountyQuery>(
+        bountyKeys.detail(bountyId),
+      );
+      const totalAmount = prevBounty?.bounty?.rewardAmount ?? 100;
+      const milestonesCount = prevBounty?.bounty?.milestones?.length ?? 1;
+      const amountToRelease = totalAmount / milestonesCount;
+
+      if (prevPool) {
+        const newReleased = Math.min(
+          prevPool.totalAmount,
+          prevPool.releasedAmount + amountToRelease,
+        );
+        const status =
+          newReleased >= prevPool.totalAmount
+            ? "Fully Released"
+            : "Partially Released";
+        queryClient.setQueryData(escrowKeys.pool(bountyId), {
+          ...prevPool,
+          releasedAmount: newReleased,
+          status,
+        });
+      }
+      return { prevPool };
+    },
+    onError: (_err, _vars, context) => {
+      if (context?.prevPool) {
+        queryClient.setQueryData(escrowKeys.pool(bountyId), context.prevPool);
+      }
+    },
+    onSuccess: () => {
+      queryClient.invalidateQueries({ queryKey: bountyKeys.detail(bountyId) });
+      queryClient.invalidateQueries({ queryKey: escrowKeys.pool(bountyId) });
+    },
+  });
+}
+
+export function useAdvanceContributor(bountyId: string) {
+  const queryClient = useQueryClient();
+
+  return useMutation({
+    mutationFn: async ({ contributorId }: { contributorId: string }) => {
+      await delay(1000);
+      return { contributorId };
+    },
+    onMutate: async ({ contributorId }) => {
+      await queryClient.cancelQueries({
+        queryKey: bountyKeys.detail(bountyId),
+      });
+      const previous = queryClient.getQueryData<ExtendedBountyQuery>(
+        bountyKeys.detail(bountyId),
+      );
+
+      if (previous?.bounty) {
+        const contributorProgress: ContributorProgress[] =
+          previous.bounty.contributorProgress || [];
+        const contributorIndex = contributorProgress.findIndex(
+          (c) => c.userId === contributorId,
+        );
+
+        if (contributorIndex >= 0) {
+          const milestones: Milestone[] = previous.bounty.milestones || [];
+          const currentMilestoneId =
+            contributorProgress[contributorIndex].currentMilestoneId;
+          const milestoneIndex = milestones.findIndex(
+            (m) => m.id === currentMilestoneId,
+          );
+
+          if (milestoneIndex >= 0 && milestoneIndex < milestones.length - 1) {
+            const nextMilestone = milestones[milestoneIndex + 1];
+            const newProgress = [...contributorProgress];
+            newProgress[contributorIndex] = {
+              ...newProgress[contributorIndex],
+              currentMilestoneId: nextMilestone.id,
+            };
+
+            queryClient.setQueryData<ExtendedBountyQuery>(
+              bountyKeys.detail(bountyId),
+              {
+                ...previous,
+                bounty: {
+                  ...previous.bounty,
+                  contributorProgress: newProgress,
+                },
+              },
+            );
+          }
+        }
+      }
+      return { previous };
+    },
+    onError: (_err, _vars, context) => {
+      if (context?.previous) {
+        queryClient.setQueryData(bountyKeys.detail(bountyId), context.previous);
+      }
+    },
+    onSuccess: () => {
+      queryClient.invalidateQueries({ queryKey: bountyKeys.detail(bountyId) });
+    },
+  });
+}
+
+export function useRemoveContributor(bountyId: string) {
+  const queryClient = useQueryClient();
+
+  return useMutation({
+    mutationFn: async ({ contributorId }: { contributorId: string }) => {
+      await delay(1000);
+      return { contributorId };
+    },
+    onMutate: async ({ contributorId }) => {
+      await queryClient.cancelQueries({
+        queryKey: bountyKeys.detail(bountyId),
+      });
+      const previous = queryClient.getQueryData<ExtendedBountyQuery>(
+        bountyKeys.detail(bountyId),
+      );
+
+      if (previous?.bounty) {
+        const contributorProgress: ContributorProgress[] =
+          previous.bounty.contributorProgress || [];
+        const occupied = Math.max(
+          0,
+          (previous.bounty.totalSlotsOccupied ?? 1) - 1,
+        );
+
+        queryClient.setQueryData<ExtendedBountyQuery>(
+          bountyKeys.detail(bountyId),
+          {
+            ...previous,
+            bounty: {
+              ...previous.bounty,
+              totalSlotsOccupied: occupied,
+              contributorProgress: contributorProgress.filter(
+                (c) => c.userId !== contributorId,
+              ),
+            },
+          },
+        );
+      }
+      return { previous };
+    },
+    onError: (_err, _vars, context) => {
+      if (context?.previous) {
+        queryClient.setQueryData(bountyKeys.detail(bountyId), context.previous);
+      }
+    },
+    onSuccess: () => {
+      queryClient.invalidateQueries({ queryKey: bountyKeys.detail(bountyId) });
+    },
+  });
+}
+
+export function useSendMessage(bountyId: string) {
+  return useMutation({
+    mutationFn: async ({
+      contributorId,
+      message,
+    }: {
+      contributorId: string;
+      message: string;
+    }) => {
+      await delay(1000);
+
+      if (!recordedMessages[bountyId]) {
+        recordedMessages[bountyId] = [];
+      }
+      recordedMessages[bountyId].push({
+        contributorId,
+        message,
+        timestamp: new Date().toISOString(),
+      });
+
+      return { contributorId, message };
+    },
+  });
+}
diff --git a/lib/server-graphql.ts b/lib/server-graphql.ts
index 4b9fee5c..44239c1b 100644
--- a/lib/server-graphql.ts
+++ b/lib/server-graphql.ts
@@ -25,7 +25,7 @@ export async function graphqlRequest<T>(
   const response = await fetch(GRAPHQL_URL, {
     method: "POST",
     headers,
-    body: JSON.stringify({ query, variables }),
+    body: JSON.stringify({ query: queryString, variables }),
     // Don't cache - always get fresh data
     cache: "no-store",
   });