Railway: deployment failing silently [2026 fix]

Build succeeds but service won't start; Railway environment variables aren't loaded before build phase.

Railway: Deployment Failing Silently – 2AM Fix Guide

TL;DR

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Real Console Output – Exact Error Messages

Here are the actual errors you'll see in Railway's deployment logs:

``` [Build] ✓ Build completed in 45s [Deploy] Starting service... [Deploy] Service exited with code 1 (no logs) ```

``` error: connect ECONNREFUSED 127.0.0.1:5432 at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1141:18) ```

``` Fatal: environment variable DATABASE_URL is not defined Process exited with code 127 ```

``` [Nitro] [prerender] Error rendering /: Cannot find module '@prisma/client' ```

``` Error: ENOENT: no such file or directory, open '/app/.env.production' at Object.openSync (fs.js:476:3) ```

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Broken vs. Fixed Code

❌ BROKEN: Build-Time Variable Access

```javascript // next.config.js (BROKEN) module.exports = { env: { DATABASE_URL: process.env.DATABASE_URL, API_KEY: process.env.API_KEY, }, }; ```

Problem: Railway hasn't injected these variables during npm run build. Build fails silently because webpack can't inline undefined variables.

✅ FIXED: Runtime Variable Injection

```javascript // next.config.js (FIXED) module.exports = { publicRuntimeConfig: { apiUrl: process.env.NEXT_PUBLIC_API_URL || '/api', }, serverRuntimeConfig: { databaseUrl: process.env.DATABASE_URL, apiKey: process.env.API_KEY, }, };

// pages/api/health.js import getConfig from 'next/config'; const { serverRuntimeConfig } = getConfig();

export default function handler(req, res) { if (!serverRuntimeConfig.databaseUrl) { return res.status(500).json({ error: 'DB not configured' }); } res.status(200).json({ ok: true }); } ```

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❌ BROKEN: Prisma Schema Without Fallback

```prisma // prisma/schema.prisma (BROKEN) datasource db { provider = "postgresql" url = env("DATABASE_URL") }

model User { id Int @id @default(autoincrement()) email String @unique } ```

Problem: prisma generate runs during build. If DATABASE_URL isn't set, Prisma client generation fails silently.

✅ FIXED: Conditional Generation

```json // package.json (FIXED) { "scripts": { "build": "prisma generate && next build", "start": "node -e \"require('dotenv').config();\" && next start", "railway:deploy": "npm ci && npm run build" }, "devDependencies": { "dotenv": "^16.4.5" } } ```

```bash #!/bin/bash

railway.json or Dockerfile

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Railway Configuration Fix

Add to your Railway service:

1. Go to Variables tab in Railway dashboard 2. Ensure all required vars are set (check ${} syntax) 3. In Deploy settings, set Start Command explicitly: ``` npm run start ``` 4. Set Build Command to NOT reference runtime vars: ``` npm ci && npm run build ```

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Version Uncertainty Note

I'm explicit here: This guide assumes Railway's 2026 platform behavior where build and start phases are separate. If you're on an older Railway version (pre-2024), variable timing may differ. Check your Railway dashboard's "Deployment" tab for actual phase logs. The principles remain the same, but timing might shift.

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Still Broken? Check These Too

1. Node.js version mismatch – Railway defaults to Node 18. Your app needs Node 20+? Add engines to package.json: ```json "engines": { "node": ">=20.0.0" } ``` See our guide on [Node version conflicts](/guide=node-version).

2. Missing .railwayignore – Ensure you're not ignoring node_modules if they're needed at start time. Check [what Railway ignores by default](/guide=railway-ignore).

3. Port binding issue – Railway injects $PORT at runtime. Verify your app listens on process.env.PORT || 3000, not hardcoded 3000.

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Official Documentation

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Key Takeaway

Railway's silent failures happen because build and runtime are decoupled. Your build command can't access service variables. Always validate at startup, not compile time. Use .railwayignore, explicit start commands, and conditional migrations.

Found a different variation? Drop it in the comments—if it's systematic, we'll add it here.