enisze · enisze · Jul 30, 2026 · Jul 30, 2026
diff --git a/apps/mobile/src/features/archive/archivedThreadList.test.ts b/apps/mobile/src/features/archive/archivedThreadList.test.ts
@@ -15,6 +15,7 @@ function makeProject(
     repositoryIdentity: null,
     defaultModelSelection: null,
     gitHubAccount: null,
+    worktreeBranchPrefix: null,
     scripts: [],
     createdAt: "2026-06-01T00:00:00.000Z",
     updatedAt: "2026-06-01T00:00:00.000Z",

diff --git a/apps/mobile/src/features/home/homeListItems.test.ts b/apps/mobile/src/features/home/homeListItems.test.ts
@@ -27,6 +27,7 @@ function makeProject(id: string, title: string): EnvironmentProject {
     repositoryIdentity: null,
     defaultModelSelection: null,
     gitHubAccount: null,
+    worktreeBranchPrefix: null,
     scripts: [],
     createdAt: "2026-06-01T00:00:00.000Z",
     updatedAt: "2026-06-01T00:00:00.000Z",

diff --git a/apps/mobile/src/features/home/homeThreadList.test.ts b/apps/mobile/src/features/home/homeThreadList.test.ts
@@ -19,6 +19,7 @@ function makeProject(
     repositoryIdentity: null,
     defaultModelSelection: null,
     gitHubAccount: null,
+    worktreeBranchPrefix: null,
     scripts: [],
     createdAt: "2026-06-01T00:00:00.000Z",
     updatedAt: "2026-06-01T00:00:00.000Z",

diff --git a/apps/mobile/src/features/home/homeThreadList.ts b/apps/mobile/src/features/home/homeThreadList.ts
@@ -307,6 +307,7 @@ export function buildHomeThreadGroups(input: {
             repositoryIdentity: null,
             defaultModelSelection: null,
             gitHubAccount: null,
+            worktreeBranchPrefix: null,
             scripts: [],
             createdAt: pendingTask.message.createdAt,
             updatedAt: pendingTask.message.createdAt,

diff --git a/apps/mobile/src/features/showcase/showcasePendingTasks.test.ts b/apps/mobile/src/features/showcase/showcasePendingTasks.test.ts
@@ -16,6 +16,7 @@ const projects: ReadonlyArray<EnvironmentProject> = [
     repositoryIdentity: null,
     defaultModelSelection: { instanceId: ProviderInstanceId.make("codex"), model: "gpt-5.4" },
     gitHubAccount: null,
+    worktreeBranchPrefix: null,
     scripts: [],
     createdAt: "2026-07-16T08:00:00.000Z",
     updatedAt: "2026-07-16T08:00:00.000Z",
@@ -28,6 +29,7 @@ const projects: ReadonlyArray<EnvironmentProject> = [
     repositoryIdentity: null,
     defaultModelSelection: null,
     gitHubAccount: null,
+    worktreeBranchPrefix: null,
     scripts: [],
     createdAt: "2026-07-16T08:00:00.000Z",
     updatedAt: "2026-07-16T08:00:00.000Z",

diff --git a/apps/mobile/src/features/threads/new-task-flow-provider.tsx b/apps/mobile/src/features/threads/new-task-flow-provider.tsx
@@ -261,6 +261,7 @@ export function NewTaskFlowProvider(props: React.PropsWithChildren) {
       repositoryIdentity: null,
       defaultModelSelection: editingPendingTask.modelSelection ?? null,
       gitHubAccount: null,
+      worktreeBranchPrefix: null,
       scripts: [],
       createdAt: editingPendingTask.createdAt,
       updatedAt: editingPendingTask.createdAt,

diff --git a/apps/mobile/src/features/threads/use-project-actions.ts b/apps/mobile/src/features/threads/use-project-actions.ts
@@ -74,7 +74,10 @@ export function useCreateProjectThread() {
           branch: input.branch,
           worktreePath: input.worktreePath,
           startFromOrigin: input.startFromOrigin ?? false,
-          worktreeBranchName: buildTemporaryWorktreeBranchName(randomHex),
+          worktreeBranchName: buildTemporaryWorktreeBranchName(
+            randomHex,
+            input.project.worktreeBranchPrefix,
+          ),
         }),
       });
       if (AsyncResult.isFailure(result)) {

diff --git a/apps/mobile/src/lib/repositoryGroups.test.ts b/apps/mobile/src/lib/repositoryGroups.test.ts
@@ -13,6 +13,7 @@ function makeProject(
     repositoryIdentity: null,
     defaultModelSelection: null,
     gitHubAccount: null,
+    worktreeBranchPrefix: null,
     scripts: [],
     createdAt: "2026-04-01T00:00:00.000Z",
     updatedAt: "2026-04-01T00:00:00.000Z",

diff --git a/apps/mobile/src/state/use-thread-outbox-drain.ts b/apps/mobile/src/state/use-thread-outbox-drain.ts
@@ -270,6 +270,9 @@ export function useThreadOutboxDrain(): void {
           branch: creation.branch,
           worktreePath: creation.worktreePath,
           startFromOrigin: creation.startFromOrigin ?? false,
+          // Queued creations don't carry the project's prefix; this is only the
+          // temporary branch, which the server renames to the project's
+          // configured `<prefix>/<slug>` on the first turn.
           worktreeBranchName: buildTemporaryWorktreeBranchName(randomHex),
         }),
       });

diff --git a/apps/server/src/orchestration/Layers/OrchestrationEngine.test.ts b/apps/server/src/orchestration/Layers/OrchestrationEngine.test.ts
@@ -124,6 +124,7 @@ describe("OrchestrationEngine", () => {
             model: "gpt-5-codex",
           },
           gitHubAccount: null,
+          worktreeBranchPrefix: null,
           scripts: [],
           createdAt: "2026-03-03T00:00:00.000Z",
           updatedAt: "2026-03-03T00:00:01.000Z",

diff --git a/apps/server/src/orchestration/Layers/ProjectionPipeline.ts b/apps/server/src/orchestration/Layers/ProjectionPipeline.ts
@@ -496,6 +496,7 @@ const makeOrchestrationProjectionPipeline = Effect.fn("makeOrchestrationProjecti
             workspaceRoot: event.payload.workspaceRoot,
             defaultModelSelection: event.payload.defaultModelSelection,
             gitHubAccount: event.payload.gitHubAccount ?? null,
+            worktreeBranchPrefix: event.payload.worktreeBranchPrefix ?? null,
             scripts: event.payload.scripts,
             createdAt: event.payload.createdAt,
             updatedAt: event.payload.updatedAt,
@@ -522,6 +523,9 @@ const makeOrchestrationProjectionPipeline = Effect.fn("makeOrchestrationProjecti
             ...(event.payload.gitHubAccount !== undefined
               ? { gitHubAccount: event.payload.gitHubAccount }
               : {}),
+            ...(event.payload.worktreeBranchPrefix !== undefined
+              ? { worktreeBranchPrefix: event.payload.worktreeBranchPrefix }
+              : {}),
             ...(event.payload.scripts !== undefined ? { scripts: event.payload.scripts } : {}),
             updatedAt: event.payload.updatedAt,
           });

diff --git a/apps/server/src/orchestration/Layers/ProjectionSnapshotQuery.test.ts b/apps/server/src/orchestration/Layers/ProjectionSnapshotQuery.test.ts
@@ -267,6 +267,7 @@ projectionSnapshotLayer("ProjectionSnapshotQuery", (it) => {
             model: "gpt-5-codex",
           },
           gitHubAccount: null,
+          worktreeBranchPrefix: null,
           scripts: [
             {
               id: "script-1",
@@ -383,6 +384,7 @@ projectionSnapshotLayer("ProjectionSnapshotQuery", (it) => {
             model: "gpt-5-codex",
           },
           gitHubAccount: null,
+          worktreeBranchPrefix: null,
           scripts: [
             {
               id: "script-1",

diff --git a/apps/server/src/orchestration/Layers/ProjectionSnapshotQuery.ts b/apps/server/src/orchestration/Layers/ProjectionSnapshotQuery.ts
@@ -237,6 +237,7 @@ function mapProjectShellRow(
     repositoryIdentity,
     defaultModelSelection: row.defaultModelSelection,
     gitHubAccount: row.gitHubAccount,
+    worktreeBranchPrefix: row.worktreeBranchPrefix,
     scripts: row.scripts,
     createdAt: row.createdAt,
     updatedAt: row.updatedAt,
@@ -311,6 +312,7 @@ const makeProjectionSnapshotQuery = Effect.gen(function* () {
           workspace_root AS "workspaceRoot",
           default_model_selection_json AS "defaultModelSelection",
           github_account_json AS "gitHubAccount",
+          worktree_branch_prefix AS "worktreeBranchPrefix",
           scripts_json AS "scripts",
           created_at AS "createdAt",
           updated_at AS "updatedAt",
@@ -685,6 +687,7 @@ const makeProjectionSnapshotQuery = Effect.gen(function* () {
           workspace_root AS "workspaceRoot",
           default_model_selection_json AS "defaultModelSelection",
           github_account_json AS "gitHubAccount",
+          worktree_branch_prefix AS "worktreeBranchPrefix",
           scripts_json AS "scripts",
           created_at AS "createdAt",
           updated_at AS "updatedAt",
@@ -708,6 +711,7 @@ const makeProjectionSnapshotQuery = Effect.gen(function* () {
           workspace_root AS "workspaceRoot",
           default_model_selection_json AS "defaultModelSelection",
           github_account_json AS "gitHubAccount",
+          worktree_branch_prefix AS "worktreeBranchPrefix",
           scripts_json AS "scripts",
           created_at AS "createdAt",
           updated_at AS "updatedAt",
@@ -1190,6 +1194,7 @@ const makeProjectionSnapshotQuery = Effect.gen(function* () {
                 repositoryIdentity: repositoryIdentities.get(row.projectId) ?? null,
                 defaultModelSelection: row.defaultModelSelection,
                 gitHubAccount: row.gitHubAccount,
+                worktreeBranchPrefix: row.worktreeBranchPrefix,
                 scripts: row.scripts,
                 createdAt: row.createdAt,
                 updatedAt: row.updatedAt,
@@ -1317,6 +1322,7 @@ const makeProjectionSnapshotQuery = Effect.gen(function* () {
                   workspaceRoot: row.workspaceRoot,
                   defaultModelSelection: row.defaultModelSelection,
                   gitHubAccount: row.gitHubAccount,
+                  worktreeBranchPrefix: row.worktreeBranchPrefix,
                   scripts: row.scripts,
                   createdAt: row.createdAt,
                   updatedAt: row.updatedAt,
@@ -1766,6 +1772,7 @@ const makeProjectionSnapshotQuery = Effect.gen(function* () {
                     repositoryIdentity,
                     defaultModelSelection: option.value.defaultModelSelection,
                     gitHubAccount: option.value.gitHubAccount,
+                    worktreeBranchPrefix: option.value.worktreeBranchPrefix,
                     scripts: option.value.scripts,
                     createdAt: option.value.createdAt,
                     updatedAt: option.value.updatedAt,

diff --git a/apps/server/src/orchestration/Layers/ProviderCommandReactor.ts b/apps/server/src/orchestration/Layers/ProviderCommandReactor.ts
@@ -12,7 +12,7 @@ import {
   type RuntimeMode,
   type TurnId,
 } from "@t3tools/contracts";
-import { isTemporaryWorktreeBranch, WORKTREE_BRANCH_PREFIX } from "@t3tools/shared/git";
+import { isTemporaryWorktreeBranch, sanitizeWorktreeBranchPrefix } from "@t3tools/shared/git";
 import * as Cache from "effect/Cache";
 import * as Cause from "effect/Cause";
 import * as Crypto from "effect/Crypto";
@@ -166,15 +166,16 @@ function stalePendingRequestDetail(
   return `Stale pending ${requestKind} request: ${requestId}. Provider callback state does not survive app restarts or recovered sessions. Restart the turn to continue.`;
 }
 
-function buildGeneratedWorktreeBranchName(raw: string): string {
+function buildGeneratedWorktreeBranchName(raw: string, prefix?: string | null): string {
+  const resolvedPrefix = sanitizeWorktreeBranchPrefix(prefix);
   const normalized = raw
     .trim()
     .toLowerCase()
     .replace(/^refs\/heads\//, "")
     .replace(/['"`]/g, "");
 
-  const withoutPrefix = normalized.startsWith(`${WORKTREE_BRANCH_PREFIX}/`)
-    ? normalized.slice(`${WORKTREE_BRANCH_PREFIX}/`.length)
+  const withoutPrefix = normalized.startsWith(`${resolvedPrefix}/`)
+    ? normalized.slice(`${resolvedPrefix}/`.length)
     : normalized;
 
   const branchFragment = withoutPrefix
@@ -186,7 +187,7 @@ function buildGeneratedWorktreeBranchName(raw: string): string {
     .replace(/[./_-]+$/g, "");
 
   const safeFragment = branchFragment.length > 0 ? branchFragment : "update";
-  return `${WORKTREE_BRANCH_PREFIX}/${safeFragment}`;
+  return `${resolvedPrefix}/${safeFragment}`;
 }
 
 const make = Effect.gen(function* () {
@@ -677,6 +678,7 @@ const make = Effect.gen(function* () {
     readonly threadId: ThreadId;
     readonly branch: string | null;
     readonly worktreePath: string | null;
+    readonly worktreeBranchPrefix?: string | null;
     readonly messageText: string;
     readonly attachments?: ReadonlyArray<ChatAttachment>;
   }) {
@@ -708,7 +710,10 @@ const make = Effect.gen(function* () {
       });
       if (!generated) return;
 
-      const targetBranch = buildGeneratedWorktreeBranchName(generated.branch);
+      // Prefer the project's prefix, then the global default setting; an empty
+      // string or null resolves to the built-in default inside the builder.
+      const effectivePrefix = input.worktreeBranchPrefix ?? settings.worktreeBranchPrefix;
+      const targetBranch = buildGeneratedWorktreeBranchName(generated.branch, effectivePrefix);
       if (targetBranch === oldBranch) return;
 
       const renamed = yield* gitWorkflow.renameBranch({ cwd, oldBranch, newBranch: targetBranch });
@@ -822,6 +827,7 @@ const make = Effect.gen(function* () {
         threadId: event.payload.threadId,
         branch: thread.branch,
         worktreePath: thread.worktreePath,
+        worktreeBranchPrefix: project?.worktreeBranchPrefix ?? null,
         ...generationInput,
       }).pipe(Effect.forkScoped);
 

diff --git a/apps/server/src/orchestration/commandInvariants.test.ts b/apps/server/src/orchestration/commandInvariants.test.ts
@@ -36,6 +36,7 @@ const readModel: OrchestrationReadModel = {
         model: "gpt-5-codex",
       },
       gitHubAccount: null,
+      worktreeBranchPrefix: null,
       scripts: [],
       createdAt: now,
       updatedAt: now,
@@ -50,6 +51,7 @@ const readModel: OrchestrationReadModel = {
         model: "gpt-5-codex",
       },
       gitHubAccount: null,
+      worktreeBranchPrefix: null,
       scripts: [],
       createdAt: now,
       updatedAt: now,

diff --git a/apps/server/src/orchestration/decider.ts b/apps/server/src/orchestration/decider.ts
@@ -251,6 +251,7 @@ export const decideOrchestrationCommand = Effect.fn("decideOrchestrationCommand"
           workspaceRoot: command.workspaceRoot,
           defaultModelSelection: command.defaultModelSelection ?? null,
           gitHubAccount: command.gitHubAccount ?? null,
+          worktreeBranchPrefix: command.worktreeBranchPrefix ?? null,
           scripts: [],
           createdAt: command.createdAt,
           updatedAt: command.createdAt,
@@ -289,6 +290,9 @@ export const decideOrchestrationCommand = Effect.fn("decideOrchestrationCommand"
             ? { defaultModelSelection: command.defaultModelSelection }
             : {}),
           ...(command.gitHubAccount !== undefined ? { gitHubAccount: command.gitHubAccount } : {}),
+          ...(command.worktreeBranchPrefix !== undefined
+            ? { worktreeBranchPrefix: command.worktreeBranchPrefix }
+            : {}),
           ...(command.scripts !== undefined ? { scripts: command.scripts } : {}),
           updatedAt: occurredAt,
         },

diff --git a/apps/server/src/orchestration/projector.ts b/apps/server/src/orchestration/projector.ts
@@ -212,6 +212,7 @@ export function projectEvent(
             workspaceRoot: payload.workspaceRoot,
             defaultModelSelection: payload.defaultModelSelection,
             gitHubAccount: payload.gitHubAccount ?? null,
+            worktreeBranchPrefix: payload.worktreeBranchPrefix ?? null,
             scripts: payload.scripts,
             createdAt: payload.createdAt,
             updatedAt: payload.updatedAt,
@@ -247,6 +248,9 @@ export function projectEvent(
                   ...(payload.gitHubAccount !== undefined
                     ? { gitHubAccount: payload.gitHubAccount }
                     : {}),
+                  ...(payload.worktreeBranchPrefix !== undefined
+                    ? { worktreeBranchPrefix: payload.worktreeBranchPrefix }
+                    : {}),
                   ...(payload.scripts !== undefined ? { scripts: payload.scripts } : {}),
                   updatedAt: payload.updatedAt,
                 }

diff --git a/apps/server/src/persistence/Layers/ProjectionProjects.ts b/apps/server/src/persistence/Layers/ProjectionProjects.ts
@@ -37,6 +37,7 @@ const makeProjectionProjectRepository = Effect.gen(function* () {
           workspace_root,
           default_model_selection_json,
           github_account_json,
+          worktree_branch_prefix,
           scripts_json,
           created_at,
           updated_at,
@@ -48,6 +49,7 @@ const makeProjectionProjectRepository = Effect.gen(function* () {
           ${row.workspaceRoot},
           ${row.defaultModelSelection !== null ? JSON.stringify(row.defaultModelSelection) : null},
           ${row.gitHubAccount !== null ? JSON.stringify(row.gitHubAccount) : null},
+          ${row.worktreeBranchPrefix},
           ${JSON.stringify(row.scripts)},
           ${row.createdAt},
           ${row.updatedAt},
@@ -59,6 +61,7 @@ const makeProjectionProjectRepository = Effect.gen(function* () {
           workspace_root = excluded.workspace_root,
           default_model_selection_json = excluded.default_model_selection_json,
           github_account_json = excluded.github_account_json,
+          worktree_branch_prefix = excluded.worktree_branch_prefix,
           scripts_json = excluded.scripts_json,
           created_at = excluded.created_at,
           updated_at = excluded.updated_at,
@@ -77,6 +80,7 @@ const makeProjectionProjectRepository = Effect.gen(function* () {
           workspace_root AS "workspaceRoot",
           default_model_selection_json AS "defaultModelSelection",
           github_account_json AS "gitHubAccount",
+          worktree_branch_prefix AS "worktreeBranchPrefix",
           scripts_json AS "scripts",
           created_at AS "createdAt",
           updated_at AS "updatedAt",
@@ -97,6 +101,7 @@ const makeProjectionProjectRepository = Effect.gen(function* () {
           workspace_root AS "workspaceRoot",
           default_model_selection_json AS "defaultModelSelection",
           github_account_json AS "gitHubAccount",
+          worktree_branch_prefix AS "worktreeBranchPrefix",
           scripts_json AS "scripts",
           created_at AS "createdAt",
           updated_at AS "updatedAt",

diff --git a/apps/server/src/persistence/Layers/ProjectionRepositories.test.ts b/apps/server/src/persistence/Layers/ProjectionRepositories.test.ts
@@ -34,6 +34,7 @@ projectionRepositoriesLayer("Projection repositories", (it) => {
           model: "gpt-5.4",
         },
         gitHubAccount: null,
+        worktreeBranchPrefix: null,
         scripts: [],
         createdAt: "2026-03-24T00:00:00.000Z",
         updatedAt: "2026-03-24T00:00:00.000Z",

diff --git a/apps/server/src/persistence/Migrations.ts b/apps/server/src/persistence/Migrations.ts
@@ -48,6 +48,7 @@ import Migration0032 from "./Migrations/032_AuthPairingProofKeyThumbprint.ts";
 import Migration0033 from "./Migrations/033_ProjectionThreadsSettled.ts";
 import Migration0034 from "./Migrations/034_ProjectionThreadsSnoozed.ts";
 import Migration0035 from "./Migrations/035_ProjectionProjectsGitHubAccount.ts";
+import Migration0036 from "./Migrations/036_ProjectionProjectsWorktreeBranchPrefix.ts";
 
 /**
  * Migration loader with all migrations defined inline.
@@ -95,6 +96,7 @@ export const migrationEntries = [
   [33, "ProjectionThreadsSettled", Migration0033],
   [34, "ProjectionThreadsSnoozed", Migration0034],
   [35, "ProjectionProjectsGitHubAccount", Migration0035],
+  [36, "ProjectionProjectsWorktreeBranchPrefix", Migration0036],
 ] as const;
 
 export const makeMigrationLoader = (throughId?: number) =>

diff --git a/apps/server/src/persistence/Migrations/036_ProjectionProjectsWorktreeBranchPrefix.ts b/apps/server/src/persistence/Migrations/036_ProjectionProjectsWorktreeBranchPrefix.ts
@@ -0,0 +1,16 @@
+import * as Effect from "effect/Effect";
+import * as SqlClient from "effect/unstable/sql/SqlClient";
+
+export default Effect.gen(function* () {
+  const sql = yield* SqlClient.SqlClient;
+  const columns = yield* sql<{ readonly name: string }>`
+    PRAGMA table_info(projection_projects)
+  `;
+
+  if (!columns.some((column) => column.name === "worktree_branch_prefix")) {
+    yield* sql`
+      ALTER TABLE projection_projects
+      ADD COLUMN worktree_branch_prefix TEXT
+    `;
+  }
+});
diff --git a/apps/server/src/persistence/Services/ProjectionProjects.ts b/apps/server/src/persistence/Services/ProjectionProjects.ts
@@ -26,6 +26,7 @@ export const ProjectionProject = Schema.Struct({
   workspaceRoot: Schema.String,
   defaultModelSelection: Schema.NullOr(ModelSelection),
   gitHubAccount: Schema.NullOr(GitHubAccountRef),
+  worktreeBranchPrefix: Schema.NullOr(Schema.String),
   scripts: Schema.Array(ProjectScript),
   createdAt: IsoDateTime,
   updatedAt: IsoDateTime,

diff --git a/apps/server/src/project/ProjectSetupScriptRunner.test.ts b/apps/server/src/project/ProjectSetupScriptRunner.test.ts
@@ -19,6 +19,7 @@ const makeProject = (scripts: OrchestrationProject["scripts"]): OrchestrationPro
   workspaceRoot: "/repo/project",
   defaultModelSelection: null,
   gitHubAccount: null,
+  worktreeBranchPrefix: null,
   scripts,
   createdAt: "2026-01-01T00:00:00.000Z",
   updatedAt: "2026-01-01T00:00:00.000Z",