From a0676fb1d1e14301e6b07a8eb3e7c76bd34d427d Mon Sep 17 00:00:00 2001
From: Dotta <bippadotta@protonmail.com>
Date: Thu, 24 Sep 2026 17:07:47 -0700
Subject: [PATCH] fix(heartbeat): claim issue ownership with queued runs

Co-Authored-By: Paperclip <noreply@paperclip.ing>
---
 ...heartbeat-stale-queue-invalidation.test.ts | 32 +++++++++++++++++
 server/src/services/heartbeat.ts              | 35 +++++++++++++++++--
 2 files changed, 64 insertions(+), 3 deletions(-)

diff --git a/server/src/__tests__/heartbeat-stale-queue-invalidation.test.ts b/server/src/__tests__/heartbeat-stale-queue-invalidation.test.ts
index fc71329a30a..4d49def6677 100644
--- a/server/src/__tests__/heartbeat-stale-queue-invalidation.test.ts
+++ b/server/src/__tests__/heartbeat-stale-queue-invalidation.test.ts
@@ -311,6 +311,38 @@ describeEmbeddedPostgres("heartbeat stale queued-run invalidation", () => {
     });
   }
 
+  it.each([true, false])("serializes assignment claims by issue without serializing unrelated work (same issue: %s)", async (sameIssue) => {
+    const { companyId, agentId } = await seedCompanyAndAgent({ maxConcurrentRuns: 2 });
+    const firstIssueId = randomUUID();
+    const secondIssueId = sameIssue ? firstIssueId : randomUUID();
+    for (const id of new Set([firstIssueId, secondIssueId])) {
+      await db.insert(issues).values({ id, companyId, title: "Concurrent assignment", status: "todo", assigneeAgentId: agentId });
+    }
+    await seedQueuedRun({ companyId, agentId, issueId: firstIssueId, wakeReason: "issue_assigned", contextExtras: { source: "issue.create" } });
+    await seedQueuedRun({ companyId, agentId, issueId: secondIssueId, wakeReason: "issue_assigned", contextExtras: { source: "issue.assigned_todo_liveness_dispatch" } });
+    let release!: () => void;
+    const gate = new Promise<void>((resolve) => { release = resolve; });
+    mockAdapterExecute.mockImplementation(async () => {
+      await gate;
+      return { exitCode: 0, signal: null, timedOut: false, errorMessage: null, summary: "Assignment finished.", provider: "test", model: "test-model" };
+    });
+    try {
+      await heartbeat.resumeQueuedRuns();
+      expect(await waitForCondition(() => Promise.resolve(mockAdapterExecute.mock.calls.length > 0))).toBe(true);
+      const runs = await db.select().from(heartbeatRuns);
+      const running = runs.filter((run) => run.status === "running");
+      expect(running).toHaveLength(sameIssue ? 1 : 2);
+      expect(runs.filter((run) => run.status === "queued")).toHaveLength(sameIssue ? 1 : 0);
+      for (const run of running) {
+        const [issue] = await db.select().from(issues).where(eq(issues.id, (run.contextSnapshot as { issueId: string }).issueId));
+        expect(issue.executionRunId).toBe(run.id);
+      }
+    } finally {
+      release();
+      await heartbeat.drainActiveRunExecutions();
+    }
+  });
+
   it("skips generic timer wakes with no actionable assigned work before adapter execution", async () => {
     const { agentId } = await seedCompanyAndAgent({
       heartbeatConfig: {
diff --git a/server/src/services/heartbeat.ts b/server/src/services/heartbeat.ts
index dca86e4abca..60181278c4c 100644
--- a/server/src/services/heartbeat.ts
+++ b/server/src/services/heartbeat.ts
@@ -17639,9 +17639,38 @@ export function heartbeatService(
               agentNameKey: normalizeAgentNameKey(agent.name),
             });
           }
-          return tx.update(heartbeatRuns).set(claimValues).where(and(
-            eq(heartbeatRuns.id, run.id), eq(heartbeatRuns.status, "queued"),
-          )).returning().then((rows) => rows[0] ?? null);
+          return tx.transaction(async (claimTx) => {
+            // Several queued assignments can enter the same admission batch
+            // before executeRun registers an in-memory owner. Claim the issue
+            // and run together, so only its exact owner reaches provider setup.
+            const issueOwner = issueId && context.wakeReason !== "source_scoped_recovery_action"
+              ? await claimTx.select({
+                  assigneeAgentId: issues.assigneeAgentId,
+                  executionRunId: issues.executionRunId,
+                  checkoutRunId: issues.checkoutRunId,
+                }).from(issues).where(and(
+                  eq(issues.id, issueId), eq(issues.companyId, run.companyId),
+                )).for("update").then((rows) => rows[0] ?? null)
+              : null;
+            if (issueOwner?.assigneeAgentId === run.agentId &&
+                ((issueOwner.executionRunId && issueOwner.executionRunId !== run.id) ||
+                 (run.scheduledRetryReason === "native_safe_replacement" &&
+                  issueOwner.checkoutRunId && issueOwner.checkoutRunId !== run.id))) {
+              return null;
+            }
+            const claimedRun = await claimTx.update(heartbeatRuns).set(claimValues).where(and(
+              eq(heartbeatRuns.id, run.id), eq(heartbeatRuns.status, "queued"),
+            )).returning().then((rows) => rows[0] ?? null);
+            if (claimedRun && issueId && issueOwner?.assigneeAgentId === run.agentId) {
+              await claimTx.update(issues).set({
+                executionRunId: claimedRun.id,
+                executionAgentNameKey: normalizeAgentNameKey(agent.name),
+                executionLockedAt: claimedAt,
+                updatedAt: claimedAt,
+              }).where(and(eq(issues.id, issueId), eq(issues.companyId, run.companyId)));
+            }
+            return claimedRun;
+          });
         });
     if (!claimed) return null;