diff --git a/electron/coding-runtime/pi/provider-config.ts b/electron/coding-runtime/pi/provider-config.ts
index a08b9ba..6b11ad8 100644
--- a/electron/coding-runtime/pi/provider-config.ts
+++ b/electron/coding-runtime/pi/provider-config.ts
@@ -22,6 +22,7 @@ import { getImportedModelProfile } from '../../../shared/imported-model-profile'
 const PI_ENV_PREFIX = 'MAKELORE_PI';
 const WORKS_SQUARE_AI_GATEWAY_CREDENTIAL_MODE = 'works_square_ai_gateway';
 const WORKS_SQUARE_AI_GATEWAY_PROXY_CREDENTIAL_MODE = 'works_square_ai_gateway_proxy';
+const providerCatalogWriteTails = new Map<string, Promise<void>>();
 
 export const PI_PROVIDER_APIS = [
   'openai-completions',
@@ -469,7 +470,18 @@ export async function writePiProviderCatalog(
   modelRef?: ProductModelRef,
 ): Promise<void> {
   if (modelRef) selectPiProviderModel(catalog, modelRef);
-  await atomicWriteJson(filePath, catalog.modelsFile);
+  const previous = providerCatalogWriteTails.get(filePath) ?? Promise.resolve();
+  const write = previous
+    .catch(() => undefined)
+    .then(async () => await atomicWriteJson(filePath, catalog.modelsFile));
+  providerCatalogWriteTails.set(filePath, write);
+  try {
+    await write;
+  } finally {
+    if (providerCatalogWriteTails.get(filePath) === write) {
+      providerCatalogWriteTails.delete(filePath);
+    }
+  }
 }
 
 function replaceCredentialEnvReferences(value: string, credential: string | null): string {
diff --git a/electron/coding-runtime/pi/release-proof.ts b/electron/coding-runtime/pi/release-proof.ts
index 757c4f8..d0ef36f 100644
--- a/electron/coding-runtime/pi/release-proof.ts
+++ b/electron/coding-runtime/pi/release-proof.ts
@@ -144,7 +144,7 @@ const EXPECTED_TURN_MILESTONES: readonly ProofMilestone[] = [
 let pressureRun: PressureRun | null = null;
 
 async function waitFor(predicate: () => boolean, message: string): Promise<void> {
-  const deadline = Date.now() + 15_000;
+  const deadline = Date.now() + 30_000;
   while (Date.now() < deadline) {
     if (predicate()) return;
     await new Promise((resolveWait) => setTimeout(resolveWait, 20));
@@ -350,7 +350,7 @@ async function createProofProjects(
   for (let index = 0; index < count; index += 1) {
     const number = index + 1;
     const projectPath = path.join(root, `project-${number}`);
-    const project = await createLocalCodingProject({ projectPath, now }, projectStore);
+    const { project } = await createLocalCodingProject({ projectPath, now }, projectStore);
     await createCodingProjectAgent(projectPath, {
       id: PROOF_AGENT_ID,
       avatarId: 'avatar-01',
@@ -661,7 +661,7 @@ async function startPressureRun(): Promise<PressureRun> {
         `release-proof-write-project-${index + 1}`,
         `release-proof-holder-${index + 1}`,
       ));
-      dispatches.push(composition.scheduler.dispatch({
+    dispatches.push(composition.scheduler.dispatch({
         conversationId: project.input.conversationId,
         workerGeneration: generation,
         runId,
@@ -676,13 +676,31 @@ async function startPressureRun(): Promise<PressureRun> {
         },
       }));
     }
-    await waitFor(
-      () => composition.processBudget.activeCount === 8
-        && composition.scheduler.getDiagnostics().activeChildPermits === 4
-        && provider.activeCounts().child === 4
-        && processIds(composition.tracked, 'child', true).length === 4,
-      'Four real ephemeral Pi children did not become active',
-    );
+    try {
+      await waitFor(
+        () => composition.processBudget.activeCount === 8
+          && composition.scheduler.getDiagnostics().activeChildPermits === 4
+          && provider.activeCounts().child === 4
+          && processIds(composition.tracked, 'child', true).length === 4,
+        'Four real ephemeral Pi children did not become active',
+      );
+    } catch (error) {
+      const childDiagnostics = composition.tracked
+        .filter(({ role }) => role === 'child')
+        .map(({ process }) => ({
+          pid: process.processId ?? null,
+          running: process.isRunning,
+          diagnostic: process.stderrDiagnostic,
+        }));
+      throw new Error(
+        `${error instanceof Error ? error.message : String(error)}: ${JSON.stringify({
+          snapshot: pressureSnapshot(composition, provider, writeLeases),
+          scheduler: composition.scheduler.getDiagnostics(),
+          providerRequests: providerRequestCounts(provider),
+          childDiagnostics,
+        })}`,
+      );
+    }
     const active = pressureSnapshot(composition, provider, writeLeases);
     if (active.parentProcessIds.length !== 4
       || active.childProcessIds.length !== 4
diff --git a/tests/unit/pi-provider-config.test.ts b/tests/unit/pi-provider-config.test.ts
index acd3fe9..0e14df2 100644
--- a/tests/unit/pi-provider-config.test.ts
+++ b/tests/unit/pi-provider-config.test.ts
@@ -194,6 +194,21 @@ describe('Pi Provider catalog', () => {
     expect(await readFile(filePath, 'utf8')).toBe('existing-catalog\n');
   });
 
+  it('serializes concurrent writes to the shared managed catalog', async () => {
+    const root = await mkdtemp(path.join(tmpdir(), 'makelore-pi-provider-concurrent-'));
+    temporaryRoots.push(root);
+    const filePath = path.join(root, 'models.json');
+    const catalog = buildPiProviderCatalog({ accounts: [account()] });
+
+    await Promise.all(Array.from({ length: 8 }, async () => await writePiProviderCatalog(
+      filePath,
+      catalog,
+      { accountId: 'account-one', modelId: 'gpt-5.4', thinkingLevel: 'off' },
+    )));
+
+    expect(JSON.parse(await readFile(filePath, 'utf8'))).toEqual(catalog.modelsFile);
+  });
+
   it('fails closed when a non-local credential is unavailable', async () => {
     const provider = account();
     const descriptor = buildPiProviderCatalog({ accounts: [provider] }).descriptors[0]!;