From 9b56cf362b98e29aab6eebbe46b6c43e304d02d7 Mon Sep 17 00:00:00 2001
From: mawkone <mark@getacquired.com>
Date: Fri, 12 Jun 2026 15:36:35 -0700
Subject: [PATCH] fix(preview): remove brittle dev server readiness probes;
 trust that the server will eventually boot

---
 vibn-frontend/app/api/mcp/route.ts            | 21 ++++++++-----------
 .../[projectId]/dev-server/ensure/route.ts    | 12 +++++++++--
 vibn-frontend/lib/dev-container.ts            |  2 +-
 3 files changed, 20 insertions(+), 15 deletions(-)

diff --git a/vibn-frontend/app/api/mcp/route.ts b/vibn-frontend/app/api/mcp/route.ts
index 56e93e47..f3679b1c 100644
--- a/vibn-frontend/app/api/mcp/route.ts
+++ b/vibn-frontend/app/api/mcp/route.ts
@@ -5311,20 +5311,17 @@ async function toolDevServerStart(
       workspace: principal.workspace,
     });
 
-    // Instead of firing-and-forgetting, we now wait for the server to ACTUALLY
-    // spin up and serve HTTP traffic before we return success to the AI.
-    // This allows the AI to see the exact health check failure synchronously.
-    let isHealthy = false;
+    // We mark it healthy immediately. Webpack compiles are taking too long
+    // on cold boots and causing the probe to fail and the AI to retry endlessly.
+    // The Traefik router will hold the connection open for the user until it responds.
+    let isHealthy = true;
     let failureOutput = "";
 
-    try {
-      await probeDevServerReadiness(project.id, row.id, row.port);
-      isHealthy = true;
-    } catch (probeErr: any) {
-      isHealthy = false;
-      failureOutput = probeErr.message || String(probeErr);
-      console.error("[dev_server.start] Synchronous probe failed:", probeErr);
-    }
+    // We still fire the probe in the background so it eventually logs if it fails,
+    // but we don't await it.
+    probeDevServerReadiness(project.id, row.id, row.port).catch((err) => {
+      console.error("[dev_server.start] Async probe failed later:", err);
+    });
 
     if (!isHealthy) {
       let recentLogs = "";
diff --git a/vibn-frontend/app/api/projects/[projectId]/dev-server/ensure/route.ts b/vibn-frontend/app/api/projects/[projectId]/dev-server/ensure/route.ts
index 0df92f29..4e0c7d7b 100644
--- a/vibn-frontend/app/api/projects/[projectId]/dev-server/ensure/route.ts
+++ b/vibn-frontend/app/api/projects/[projectId]/dev-server/ensure/route.ts
@@ -134,8 +134,16 @@ export async function POST(
         workspace,
       });
       const row = await startDevServer(restartOpts);
-      // Run the readiness probe in background so state transitions
-      // from 'starting' → 'running' (or 'failed') in the DB.
+
+      // We immediately set it to running instead of waiting for the probe.
+      // The probe has been flaky on Webpack cold compiles and causing the
+      // frontend to get stuck in a "Preview not running" loop.
+      await query(`UPDATE fs_dev_servers SET state = 'running' WHERE id = $1`, [
+        row.id,
+      ]);
+
+      // Still run the probe in the background just to log any catastrophic failures,
+      // but the UI won't be blocked by it.
       probeDevServerReadiness(project.id, row.id, row.port).catch((err) => {
         console.error("[dev-server/ensure] probe failed:", err?.message);
       });
diff --git a/vibn-frontend/lib/dev-container.ts b/vibn-frontend/lib/dev-container.ts
index 66824f9f..8808a9c5 100644
--- a/vibn-frontend/lib/dev-container.ts
+++ b/vibn-frontend/lib/dev-container.ts
@@ -760,7 +760,7 @@ export async function probeDevServerReadiness(
     `for i in $(seq 1 300); do ` +
     `for path in / ''; do ` +
     `code=$(curl -sS -o /dev/null -w '%{http_code}' --max-time 2 --connect-timeout 2 ` +
-    `"http://127.0.0.1:${port}$path" 2>/dev/null || printf '000'); ` +
+    `"http://localhost:${port}$path" 2>/dev/null || curl -sS -o /dev/null -w '%{http_code}' --max-time 2 --connect-timeout 2 "http://0.0.0.0:${port}$path" 2>/dev/null || printf '000'); ` +
     `last_code=$code; ` +
     `[ "$code" != "000" ] && [ -n "$code" ] && exit 0; ` +
     `done; ` +