Railway: deployment failing silently [2026 fix]
Build succeeds but service won't start; Railway doesn't report errors. Fix: Add explicit start command and check build logs panel.
Railway: Deployment Failing Silently – 2am Emergency Fix
TL;DR
Cause: Railway's build succeeds but your app crashes on startup because the start command is missing or wrong, and error logs aren't displayed in the main deploy UI. Fix: Addstart command to package.json or set RAILWAY_CMD environment variable, then check the Build Logs tab (not Deploy tab) for actual errors.---
Real Console Error Messages
Here are the exact outputs you'll see when this breaks:
``` [2026-01-15T02:47:33.221Z] ✓ Build successful [2026-01-15T02:47:45.112Z] ✓ Starting service... [2026-01-15T02:48:01.890Z] Service stopped unexpectedly (exit code 1) ```
``` Error: Cannot find module 'express' at Function.Module._load (internal/modules/require.js:217:19) at Module._require (internal/modules/js:689:11) at Object.<anonymous> (/app/server.js:1:17) ```
``` [Railway] No start command found. Defaulting to 'npm start' npm ERR! missing script: start npm ERR! Did you mean one of these? npm ERR! npm run build ```
``` [Build] Running npm install... [Build] added 145 packages [Deploy] Container started [Deploy] Container exited with status 137 (OOM Kill) ```
``` [Railway] Process exited with code 127 /bin/sh: 1: node: not found ```
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The Problem: Broken vs. Fixed Code
❌ BROKEN: Missing Start Command
```json // package.json { "name": "my-app", "version": "1.0.0", "scripts": { "dev": "nodemon server.js", "build": "tsc" }, "dependencies": { "express": "^4.18.2" } } ```
✅ FIXED: Explicit Start Command
```json // package.json { "name": "my-app", "version": "1.0.0", "scripts": { "dev": "nodemon server.js", "build": "tsc", "start": "node dist/server.js" }, "dependencies": { "express": "^4.18.2" } } ```
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❌ BROKEN: Wrong Environment Variables
```bash
.env (or Railway env vars)
PORT=3000 NODE_ENV=productionMissing DATABASE_URL or API keys
```App starts, connects to undefined database, crashes silently after 2-3 seconds.
✅ FIXED: Complete Environment Setup
```bash
Railway Variables tab
PORT=3000 NODE_ENV=production DATABASE_URL=postgresql://user:pass@localhost/dbname API_KEY=your-actual-key-here RAILWAY_BUILDER=nixpacks ```Then in your code: ```javascript const dbUrl = process.env.DATABASE_URL; if (!dbUrl) { throw new Error('DATABASE_URL is required'); } ```
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Why This Happens
1. Railway's build layer (nixpacks) succeeds because it just installs dependencies
2. The runtime layer tries to start your app but has no explicit command, so it guesses npm start
3. Your app crashes immediately because:
- Missing start script → npm error
- Missing env vars → app can't connect to services
- Missing build step → TypeScript not compiled
4. The error doesn't bubble up to the main Dashboard because Railway logs the crash in the Build Logs tab, not the Deploy tab (where you're looking)
---
Step-by-Step Fix
Step 1: Add Start Script
Openpackage.json and ensure you have:
```json
"scripts": {
"start": "node server.js"
}
```If TypeScript: "start": "node dist/server.js"
Step 2: Check Build Logs
In Railway Dashboard: 1. Go to your service 2. Click "Build Logs" tab (not Deploys) 3. Scroll to the bottom—you'll see the actual errorStep 3: Verify Environment Variables
Railway Dashboard → Variables tab. Add any missing:DATABASE_URLAPI_KEYSNODE_ENV=productionStep 4: Redeploy
Push a commit or click "Trigger Deploy" in Railway Dashboard.---
Still Broken? Check These Too
1. Out of Memory (OOM Kill) – Exit code 137 means Railway killed your container. Check for memory leaks or set smaller node --max-old-space-size=512 in your start command.
2. Node/npm Version Mismatch – Railway uses nixpacks, which infers Node version from .nvmrc or package.json engines field. If your code needs Node 18+ but Railway detected Node 14, add "engines": {"node": "18.x"} to package.json.
3. Missing Build Step – TypeScript/Next.js/Vue apps need build before start. Set Railway's RAILWAY_CMD to npm run build && npm start or use a Dockerfile for full control. See [Docker deployment guide](/?guide=railway-docker).
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Related Guides
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Official Resources
I'm explicitly uncertain: Exact behavior of Railway's auto-detection differs between nixpacks versions (as of 2026, v0.24+). If you're on an older version, your error may differ slightly. Check Railway's version in Build Logs.
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**Found a different variation? Drop it in the comments—we'll add it here.