refactor(database): move task runtime ownership to leases

src/main/database/crash-recovery-helpers.ts

@@ -15,8 +15,8 @@ export interface StaleRunDb {
   interruptRunningRuns(ts: string): number;
   /** Mark tasks associated with interrupted runs as 'blocked'. */
   blockInterruptedTasks(ts: string): void;
-  /** Clear active_run_id on tasks whose run is now interrupted. */
-  clearActiveRunIds(): void;
+  /** Delete task lease rows whose run is now interrupted. */
+  clearInterruptedTaskLeases(): void;
   /** Reset all running agents to idle. */
   resetAgentsToIdle(ts: string): void;
   /** Release all workspace locks. */
@@ -51,7 +51,7 @@ export function interruptStaleRunsLogic(
     if (interruptedCount > 0) {
       db.blockInterruptedTasks(ts);
     }
-    db.clearActiveRunIds();
+    db.clearInterruptedTaskLeases();
     db.resetAgentsToIdle(ts);
     db.releaseAllWorkspaceLocks();
   });

src/main/database/entity-crud.ts

@@ -53,7 +53,7 @@ export function buildEntityCrudMethods(
     getTask(id: string): TaskRecord {
       const row = getDb()
         .prepare(
-          "select id, company_id as companyId, project_id as projectId, goal_id as goalId, parent_id as parentId, title, description, assignee_agent_id as assigneeAgentId, workspace_id as workspaceId, status, priority, active_run_id as activeRunId, cost_usd as costUsd, task_type as taskType, requires_user_review as requiresUserReview, requires_filesystem as requiresFilesystem, started_at as startedAt, completed_at as completedAt, cancelled_at as cancelledAt, created_at as createdAt, updated_at as updatedAt from tasks where id = ?",
+          "select id, company_id as companyId, project_id as projectId, goal_id as goalId, parent_id as parentId, title, description, assignee_agent_id as assigneeAgentId, workspace_id as workspaceId, status, priority, (select l.run_id from task_leases l where l.task_id = tasks.id) as activeRunId, cost_usd as costUsd, task_type as taskType, requires_user_review as requiresUserReview, requires_filesystem as requiresFilesystem, started_at as startedAt, completed_at as completedAt, cancelled_at as cancelledAt, created_at as createdAt, updated_at as updatedAt from tasks where id = ?",
         )
         .get(id) as TaskRecord | undefined;
       if (!row) throw new Error(`Task not found: ${id}`);

src/main/database/migrations/v57-task-leases.ts

@@ -0,0 +1,121 @@
+import type { DatabaseSync } from "node:sqlite";
+import { STALE_LOCK_TIMEOUT_MS } from "../../constants";
+import { columnExists, nowIso, tableExists } from "./types";
+
+export const TASK_LEASE_SCHEMA_VERSION = 57;
+export const TASK_LEASE_SCHEMA_NAME = "task_leases_runtime_ownership";
+
+const LEASE_SECONDS = Math.floor(STALE_LOCK_TIMEOUT_MS / 1000);
+
+export function migrateTaskLeasesV57(db: DatabaseSync): void {
+  installTaskLeasesTable(db);
+  backfillTaskLeases(db);
+  dropTaskOwnershipColumns(db);
+  db
+    .prepare("insert or replace into schema_migrations (version, name, applied_at) values (?, ?, ?)")
+    .run(TASK_LEASE_SCHEMA_VERSION, TASK_LEASE_SCHEMA_NAME, nowIso());
+  assertTaskLeasesV57(db);
+}
+
+export function assertTaskLeasesV57(db: DatabaseSync): void {
+  if (!tableExists(db, "task_leases")) {
+    throw new Error("Schema v57 drift: task_leases table is missing.");
+  }
+  if (!tableExists(db, "tasks")) {
+    throw new Error("Schema v57 drift: tasks table is missing.");
+  }
+
+  const leaseColumns = db
+    .prepare("pragma table_info(task_leases)")
+    .all()
+    .map((row) => row as { name: string; type: string; notnull: number; pk: number });
+  const expectedLeaseColumns = [
+    ["task_id", "TEXT", 0, 1],
+    ["company_id", "TEXT", 1, 0],
+    ["run_id", "TEXT", 1, 0],
+    ["agent_id", "TEXT", 1, 0],
+    ["acquired_at", "TEXT", 1, 0],
+    ["renewed_at", "TEXT", 1, 0],
+    ["expires_at", "TEXT", 1, 0],
+    ["created_at", "TEXT", 1, 0],
+    ["updated_at", "TEXT", 1, 0],
+  ];
+  const actualLeaseColumns = leaseColumns.map((column) => [
+    column.name,
+    column.type.toUpperCase(),
+    column.notnull,
+    column.pk,
+  ]);
+  if (JSON.stringify(actualLeaseColumns) !== JSON.stringify(expectedLeaseColumns)) {
+    throw new Error("Schema v57 drift: task_leases columns do not match the canonical schema.");
+  }
+
+  const columns = new Set(
+    db.prepare("pragma table_info(tasks)").all().map((row) => (row as { name: string }).name),
+  );
+  for (const column of ["active_run_id", "checkout_run_id", "execution_locked_at", "active_session_id"]) {
+    if (columns.has(column)) {
+      throw new Error(`Schema v57 drift: tasks.${column} should be stored in task_leases.`);
+    }
+  }
+}
+
+function installTaskLeasesTable(db: DatabaseSync): void {
+  db.exec(`
+    create table if not exists task_leases (
+      task_id text primary key references tasks(id) on delete cascade,
+      company_id text not null,
+      run_id text not null unique references runs(id) on delete cascade,
+      agent_id text not null references agents(id) on delete cascade,
+      acquired_at text not null,
+      renewed_at text not null,
+      expires_at text not null,
+      created_at text not null,
+      updated_at text not null
+    );
+    create index if not exists idx_task_leases_company_agent on task_leases(company_id, agent_id);
+    create index if not exists idx_task_leases_expires_at on task_leases(expires_at);
+  `);
+}
+
+function backfillTaskLeases(db: DatabaseSync): void {
+  if (!tableExists(db, "tasks") || !tableExists(db, "runs")) return;
+  if (!columnExists(db, "tasks", "checkout_run_id") && !columnExists(db, "tasks", "active_run_id")) return;
+
+  const runExpr = [
+    columnExists(db, "tasks", "checkout_run_id") ? "t.checkout_run_id" : "NULL",
+    columnExists(db, "tasks", "active_run_id") ? "t.active_run_id" : "NULL",
+  ].join(", ");
+  const lockExpr = columnExists(db, "tasks", "execution_locked_at")
+    ? "coalesce(t.execution_locked_at, t.updated_at)"
+    : "t.updated_at";
+  const ts = nowIso();
+
+  db.exec(`
+    insert or ignore into task_leases (
+      task_id, company_id, run_id, agent_id, acquired_at, renewed_at, expires_at, created_at, updated_at
+    )
+    select t.id,
+           t.company_id,
+           coalesce(${runExpr}) as run_id,
+           r.agent_id,
+           ${lockExpr} as acquired_at,
+           ${lockExpr} as renewed_at,
+           strftime('%Y-%m-%dT%H:%M:%fZ', ${lockExpr}, '+${LEASE_SECONDS} seconds') as expires_at,
+           '${ts}' as created_at,
+           '${ts}' as updated_at
+    from tasks t
+    join runs r on r.id = coalesce(${runExpr})
+    where coalesce(${runExpr}) is not null
+      and r.status in ('queued', 'running')
+  `);
+}
+
+function dropTaskOwnershipColumns(db: DatabaseSync): void {
+  if (!tableExists(db, "tasks")) return;
+  for (const column of ["active_run_id", "checkout_run_id", "execution_locked_at", "active_session_id"]) {
+    if (columnExists(db, "tasks", column)) {
+      db.exec(`alter table tasks drop column ${column}`);
+    }
+  }
+}

src/main/database/runs.ts

@@ -215,35 +215,26 @@ export function buildRunMethods(
             input.status, input.summary ?? "", input.errorMessage, input.exitCode,
             input.signal, input.model, runCostUsd,
             input.unattributedCost ? 1 : 0, usageStatus, ts, ts, input.runId,
-          );
+        );
         if (run.taskId !== null) {
-          getDb().prepare("update tasks set active_run_id = null, updated_at = ? where id = ?").run(ts, run.taskId);
           getDb()
-            .prepare("UPDATE tasks SET checkout_run_id = NULL, execution_locked_at = NULL, updated_at = ? WHERE id = ? AND checkout_run_id = ?")
-            .run(ts, run.taskId, input.runId);
+            .prepare("delete from task_leases where task_id = ? and run_id = ?")
+            .run(run.taskId, input.runId);
           if (runNeverStarted) {
             // Roll the task back to `todo` when no *other* live run claims
             // it. Invariant: `task.status = 'in_progress'` ⇒ a queued or
-            // running run owns it. We drop the previous
-            // `checkout_run_id IS NULL AND active_run_id IS NULL` guard
-            // because the conditional UPDATE two lines up can miss (race:
-            // checkout_run_id already swapped to a newer run id), which
-            // would leave the task silently stuck at in_progress. The
-            // NOT EXISTS clause is the canonical "no live owner" check.
+            // running run owns it through `task_leases`.
             getDb()
               .prepare(
                 `UPDATE tasks
                  SET status = 'todo',
-                     checkout_run_id = NULL,
-                     execution_locked_at = NULL,
                      updated_at = ?
                  WHERE id = ?
                    AND status = 'in_progress'
                    AND NOT EXISTS (
-                     SELECT 1 FROM runs r
-                     WHERE r.task_id = tasks.id
-                       AND r.id != ?
-                       AND r.status IN ('queued', 'running')
+                     SELECT 1 FROM task_leases l
+                     WHERE l.task_id = tasks.id
+                       AND l.run_id != ?
                    )`,
               )
               .run(ts, run.taskId, input.runId);
@@ -291,10 +282,9 @@ export function buildRunMethods(
         )
         .run(summary, "aborted_before_usage", ts, ts, runId);
       if (taskId !== null) {
-        getDb().prepare("update tasks set active_run_id = null, updated_at = ? where id = ?").run(ts, taskId);
         getDb()
-          .prepare("UPDATE tasks SET checkout_run_id = NULL, execution_locked_at = NULL, updated_at = ? WHERE id = ? AND checkout_run_id = ?")
-          .run(ts, taskId, runId);
+          .prepare("delete from task_leases where task_id = ? and run_id = ?")
+          .run(taskId, runId);
       }
       if (workspaceId) {
         getDb()
@@ -308,12 +298,29 @@ export function buildRunMethods(
     },
 
     hasActiveRun(filter: { companyId: string; taskId?: string; agentId?: string }) {
+      if (filter.taskId) {
+        const whereClauses = [
+          "l.company_id = ?",
+          "l.task_id = ?",
+          "r.status in ('queued', 'running')",
+        ];
+        const params: SQLInputValue[] = [filter.companyId, filter.taskId];
+        if (filter.agentId) {
+          whereClauses.push("r.agent_id = ?");
+          params.push(filter.agentId);
+        }
+        const row = getDb().prepare(
+          `select 1 as present
+             from task_leases l
+             join runs r on r.id = l.run_id
+            where ${whereClauses.join(" and ")}
+            limit 1`,
+        ).get(...params) as { present: number } | undefined;
+        return Boolean(row?.present);
+      }
+
       const whereClauses = ["company_id = ?", "status in ('queued', 'running')"];
       const params: SQLInputValue[] = [filter.companyId];
-      if (filter.taskId) {
-        whereClauses.push("task_id = ?");
-        params.push(filter.taskId);
-      }
       if (filter.agentId) {
         whereClauses.push("agent_id = ?");
         params.push(filter.agentId);

src/main/database/schema.ts

@@ -9,11 +9,18 @@ import {
   markBaselineSchema,
   upgradeLegacyProfileToBaselineV56,
 } from "./migrations/legacy-to-v56";
+import {
+  TASK_LEASE_SCHEMA_VERSION,
+  assertTaskLeasesV57,
+  migrateTaskLeasesV57,
+} from "./migrations/v57-task-leases";
 import {
   type ReadAll,
   type Transaction,
 } from "./migrations/types";
 
+const LATEST_SCHEMA_VERSION = TASK_LEASE_SCHEMA_VERSION;
+
 export function initializeDatabase(
   db: DatabaseSync,
   ra: ReadAll,
@@ -23,8 +30,16 @@ export function initializeDatabase(
   db.exec("create table if not exists schema_migrations (version integer primary key, name text not null, applied_at text not null)");
 
   const currentVersion = currentSchemaVersion(db);
-  if (currentVersion > BASELINE_SCHEMA_VERSION) {
-    throw new Error(`Profile schema version ${currentVersion} is newer than this app baseline ${BASELINE_SCHEMA_VERSION}.`);
+  if (currentVersion > LATEST_SCHEMA_VERSION) {
+    throw new Error(`Profile schema version ${currentVersion} is newer than this app schema ${LATEST_SCHEMA_VERSION}.`);
+  }
+
+  if (currentVersion === LATEST_SCHEMA_VERSION) {
+    tx(() => {
+      seedSettings(db);
+      assertTaskLeasesV57(db);
+    });
+    return;
   }
 
   if (currentVersion === BASELINE_SCHEMA_VERSION) {
@@ -33,6 +48,7 @@ export function initializeDatabase(
       markBaselineSchema(db);
       seedSettings(db);
       assertBaselineSchema(db);
+      migrateTaskLeasesV57(db);
     });
     return;
   }
@@ -44,6 +60,7 @@ export function initializeDatabase(
       upgradeLegacyProfileToBaselineV56({ db, readAll: ra });
       seedSettings(db);
       assertBaselineSchema(db);
+      migrateTaskLeasesV57(db);
     });
     return;
   }
@@ -53,6 +70,7 @@ export function initializeDatabase(
     markBaselineSchema(db);
     seedSettings(db);
     assertBaselineSchema(db);
+    migrateTaskLeasesV57(db);
   });
 }
 

src/main/database/snapshot.ts

@@ -83,7 +83,7 @@ export function buildSnapshotMethods(
         ...companyArgs,
       ),
       tasks: readAll<TaskRecord>(
-        `select id, company_id as companyId, project_id as projectId, goal_id as goalId, parent_id as parentId, title, description, assignee_agent_id as assigneeAgentId, workspace_id as workspaceId, status, priority, active_run_id as activeRunId, cost_usd as costUsd, task_type as taskType, requires_user_review as requiresUserReview, requires_filesystem as requiresFilesystem, started_at as startedAt, completed_at as completedAt, cancelled_at as cancelledAt, created_at as createdAt, updated_at as updatedAt from tasks${companyWhere} order by created_at desc limit 2000`,
+        `select id, company_id as companyId, project_id as projectId, goal_id as goalId, parent_id as parentId, title, description, assignee_agent_id as assigneeAgentId, workspace_id as workspaceId, status, priority, (select l.run_id from task_leases l where l.task_id = tasks.id) as activeRunId, cost_usd as costUsd, task_type as taskType, requires_user_review as requiresUserReview, requires_filesystem as requiresFilesystem, started_at as startedAt, completed_at as completedAt, cancelled_at as cancelledAt, created_at as createdAt, updated_at as updatedAt from tasks${companyWhere} order by created_at desc limit 2000`,
         ...companyArgs,
       ).map((record) => ({ ...record, requiresUserReview: toBoolean(record.requiresUserReview), requiresFilesystem: toBoolean(record.requiresFilesystem), startedAt: record.startedAt ?? null, completedAt: record.completedAt ?? null, cancelledAt: record.cancelledAt ?? null })) as TaskRecord[],
       approvals: readAll<ApprovalRecord>(

src/main/database/task-checkout.ts

@@ -1,16 +1,25 @@
 import type { DatabaseSync } from "node:sqlite";
+import { STALE_LOCK_TIMEOUT_MS } from "../constants";
 
 function isoFromMs(ms: number): string {
   return new Date(ms).toISOString();
 }
 
-function assertRunExists(db: DatabaseSync, runId: string): void {
+function loadRunForCheckout(
+  db: DatabaseSync,
+  taskId: string,
+  runId: string,
+): { companyId: string; agentId: string; taskId: string | null } {
   const row = db
-    .prepare("SELECT 1 AS present FROM runs WHERE id = ?")
-    .get(runId) as { present: number } | undefined;
+    .prepare("SELECT company_id as companyId, agent_id as agentId, task_id as taskId FROM runs WHERE id = ?")
+    .get(runId) as { companyId: string; agentId: string; taskId: string | null } | undefined;
   if (!row) {
     throw new Error(`Run not found for task checkout: ${runId}`);
   }
+  if (row.taskId !== null && row.taskId !== taskId) {
+    throw new Error(`Run ${runId} is bound to task ${row.taskId}, not ${taskId}.`);
+  }
+  return row;
 }
 
 export function checkoutTaskInTransaction(
@@ -18,26 +27,50 @@ export function checkoutTaskInTransaction(
   taskId: string,
   runId: string,
 ): boolean {
-  assertRunExists(db, runId);
+  const run = loadRunForCheckout(db, taskId, runId);
   const nowMs = Date.now();
   const ts = isoFromMs(nowMs);
   const result = db
     .prepare(
       `UPDATE tasks
-       SET checkout_run_id = ?,
-           active_run_id = ?,
-           execution_locked_at = ?,
-           status = 'in_progress',
+       SET status = 'in_progress',
+           started_at = coalesce(started_at, ?),
            updated_at = ?
      WHERE id = ?
-       AND checkout_run_id IS NULL
-       AND status IN ('todo', 'backlog')`,
+       AND company_id = ?
+       AND status IN ('todo', 'backlog')
+       AND NOT EXISTS (
+         SELECT 1 FROM task_leases
+         WHERE task_leases.task_id = tasks.id
+       )`,
     )
-    .run(runId, runId, ts, ts, taskId);
+    .run(ts, ts, taskId, run.companyId);
 
   if (result.changes === 0) {
     return false;
   }
 
+  if (run.taskId === null) {
+    db.prepare("update runs set task_id = ?, updated_at = ? where id = ? and task_id is null").run(taskId, ts, runId);
+  }
+
+  db
+    .prepare(
+      `insert into task_leases (
+        task_id, company_id, run_id, agent_id, acquired_at, renewed_at, expires_at, created_at, updated_at
+      ) values (?, ?, ?, ?, ?, ?, ?, ?, ?)`,
+    )
+    .run(
+      taskId,
+      run.companyId,
+      runId,
+      run.agentId,
+      ts,
+      ts,
+      isoFromMs(nowMs + STALE_LOCK_TIMEOUT_MS),
+      ts,
+      ts,
+    );
+
   return true;
 }

src/main/database/task-queries.ts

@@ -25,7 +25,7 @@ export function buildTaskQueryMethods(
     ): TaskRecord[] {
       const placeholders = statuses.map(() => "?").join(",");
       return readAll<TaskRecord>(
-        `select id, company_id as companyId, project_id as projectId, goal_id as goalId, parent_id as parentId, title, description, assignee_agent_id as assigneeAgentId, workspace_id as workspaceId, status, priority, active_run_id as activeRunId, cost_usd as costUsd, task_type as taskType, created_at as createdAt, updated_at as updatedAt
+        `select id, company_id as companyId, project_id as projectId, goal_id as goalId, parent_id as parentId, title, description, assignee_agent_id as assigneeAgentId, workspace_id as workspaceId, status, priority, (select l.run_id from task_leases l where l.task_id = tasks.id) as activeRunId, cost_usd as costUsd, task_type as taskType, created_at as createdAt, updated_at as updatedAt
          from tasks
         where company_id = ? and assignee_agent_id = ? and status in (${placeholders})
         order by
@@ -91,7 +91,7 @@ export function buildTaskQueryMethods(
     ): TaskListByStatusesRow[] {
       const placeholders = statuses.map(() => "?").join(", ");
       return readAll<TaskListByStatusesRow & { requiresUserReview: number | boolean }>(
-        `select id, company_id as companyId, project_id as projectId, goal_id as goalId, parent_id as parentId, title, description, assignee_agent_id as assigneeAgentId, workspace_id as workspaceId, status, priority, active_run_id as activeRunId, cost_usd as costUsd, requires_user_review as requiresUserReview, started_at as startedAt, completed_at as completedAt, cancelled_at as cancelledAt, created_at as createdAt, updated_at as updatedAt from tasks where company_id = ? and status in (${placeholders}) order by created_at desc`,
+        `select id, company_id as companyId, project_id as projectId, goal_id as goalId, parent_id as parentId, title, description, assignee_agent_id as assigneeAgentId, workspace_id as workspaceId, status, priority, (select l.run_id from task_leases l where l.task_id = tasks.id) as activeRunId, cost_usd as costUsd, requires_user_review as requiresUserReview, started_at as startedAt, completed_at as completedAt, cancelled_at as cancelledAt, created_at as createdAt, updated_at as updatedAt from tasks where company_id = ? and status in (${placeholders}) order by created_at desc`,
         companyId,
         ...statuses,
       ).map((t) => ({

src/main/database/task-sessions-crud.ts

@@ -7,9 +7,9 @@ import { type ReadAll, type Transaction, nowIso } from "./helpers";
  * Agent-scoped session lifecycle. Sessions belong to agents, not
  * tasks — `agents.session_id` is the canonical pointer, and
  * `task_sessions` rows are looked up by their own primary key only.
- * The pre-migration `tasks.active_session_id` / `task_sessions.task_id`
- * columns were dropped by v41; any read that still needs a session
- * given a task id resolves it through the task's assignee agent.
+ * Legacy task/session pointer columns were dropped by v41; any read
+ * that still needs a session given a task id resolves it through the
+ * task's assignee agent.
  */
 export function buildTaskSessionMethods(
   getDb: () => DatabaseSync,

src/main/database/task-status-rules.ts

@@ -37,12 +37,5 @@ export function buildTaskStatusTransition(
   } else {
     sets.push("cancelled_at = NULL");
   }
-  if (newStatus !== "in_progress") {
-    sets.push("checkout_run_id = NULL");
-  }
-  if (newStatus === "todo" || newStatus === "backlog") {
-    sets.push("active_run_id = NULL");
-  }
-
   return { sets, values };
 }

src/main/database/tasks-crud.ts

@@ -158,13 +158,8 @@ export function buildTaskCrudMethods(
             )
             .run("Task deleted.", "aborted_before_usage", ts, ts, run.id);
           getDb()
-            .prepare("update tasks set active_run_id = null, updated_at = ? where id = ?")
-            .run(ts, run.taskId);
-          getDb()
-            .prepare(
-              "UPDATE tasks SET checkout_run_id = NULL, execution_locked_at = NULL, updated_at = ? WHERE id = ? AND checkout_run_id = ?",
-            )
-            .run(ts, run.taskId, run.id);
+            .prepare("delete from task_leases where task_id = ? and run_id = ?")
+            .run(run.taskId, run.id);
           if (run.workspaceId) {
             getDb()
               .prepare(

src/main/database/tasks-status.ts

@@ -10,6 +10,7 @@ import { chooseBestTaskAssignee } from "./task-assignment";
 import { checkoutTaskInTransaction } from "./task-checkout";
 import { guardInReviewHasReviewer } from "./task-review-guard";
 import { assertValidTaskStatus, buildTaskStatusTransition } from "./task-status-rules";
+import { STALE_LOCK_TIMEOUT_MS } from "../constants";
 
 export function buildTaskStatusMethods(
   getDb: () => DatabaseSync,
@@ -52,6 +53,9 @@ export function buildTaskStatusMethods(
             `UPDATE tasks SET ${transition.sets.join(", ")} WHERE id = ?`,
           )
           .run(...transition.values, taskId);
+        if (newStatus !== "in_progress") {
+          getDb().prepare("delete from task_leases where task_id = ?").run(taskId);
+        }
       });
 
       if (comment) {
@@ -77,7 +81,8 @@ export function buildTaskStatusMethods(
         `select t.id, t.company_id as companyId, t.project_id as projectId, t.goal_id as goalId,
               t.parent_id as parentId, t.title, t.description,
               t.assignee_agent_id as assigneeAgentId, t.workspace_id as workspaceId,
-              t.status, t.priority, t.active_run_id as activeRunId,
+              t.status, t.priority,
+              (select l.run_id from task_leases l where l.task_id = t.id) as activeRunId,
               t.cost_usd as costUsd,
               t.created_at as createdAt, t.updated_at as updatedAt
        from tasks t
@@ -94,21 +99,19 @@ export function buildTaskStatusMethods(
     },
 
     releaseTaskLock(taskId: string, runId: string): void {
-      const ts = nowIso();
       getDb()
-        .prepare(
-          "UPDATE tasks SET checkout_run_id = NULL, execution_locked_at = NULL, updated_at = ? WHERE id = ? AND checkout_run_id = ?",
-        )
-        .run(ts, taskId, runId);
+        .prepare("delete from task_leases where task_id = ? and run_id = ?")
+        .run(taskId, runId);
     },
 
     renewTaskLease(taskId: string, runId: string): boolean {
       const ts = nowIso();
+      const expiresAt = new Date(Date.now() + STALE_LOCK_TIMEOUT_MS).toISOString();
       const result = getDb()
         .prepare(
-          "UPDATE tasks SET execution_locked_at = ?, updated_at = ? WHERE id = ? AND checkout_run_id = ?",
+          "update task_leases set renewed_at = ?, expires_at = ?, updated_at = ? where task_id = ? and run_id = ?",
         )
-        .run(ts, ts, taskId, runId);
+        .run(ts, expiresAt, ts, taskId, runId);
       return result.changes > 0;
     },