Deploy an Express app

// package.json
"scripts": {
  "start": "node index.js"
}

// index.js
const express = require("express");
const app = express();

app.set("trust proxy", 1);
app.get("/healthz", (req, res) => res.send("ok"));

app.listen(process.env.PORT || 3000);

We build on Node 22 unless engines.node in package.json asks for another version. For TypeScript, add a build script (tsc) and start the compiled output (node dist/index.js). The Node.js guide covers TypeScript and monorepos in more detail.

HTTPS ends at the platform's proxy, so your app sees plain HTTP. With app.set("trust proxy", 1), Express reads X-Forwarded-Proto: req.secure is true and cookies marked secure are actually sent.

Without it, express-session silently drops a secure session cookie and users can never stay logged in, and express-rate-limit logs an ERR_ERL_UNEXPECTED_X_FORWARDED_FOR validation error.

Every deploy requests your health check path (/ by default) and only goes live once it returns a 2xx or 3xx status. The platform keeps checking it after that. If / returns 404 or needs a login, add a route like /healthz that returns 200 and set it as the Health Check Path in Settings. Otherwise the deploy fails and the previous version keeps serving.

express-session's default MemoryStore lives in the process, so every deploy logs everyone out. Store sessions in a Redis or Postgres addon:

const session = require("express-session");
const { RedisStore } = require("connect-redis");
const { createClient } = require("redis");

const redis = createClient({ url: process.env.REDIS_URL });
redis.connect();

app.use(session({
  store: new RedisStore({ client: redis }),
  secret: process.env.SESSION_SECRET,
  resave: false,
  saveUninitialized: false,
  cookie: { secure: true },
}));

Add a Postgres addon and DATABASE_URL is injected automatically. The database is on a private network, so no SSL options are needed:

const { Pool } = require("pg");
const pool = new Pool({ connectionString: process.env.DATABASE_URL });

Run migrations (Prisma, Drizzle, Knex) from the Build command or in front of the start command, for example npx prisma migrate deploy && node index.js.

On each deploy the new container starts first, and the old one is stopped once the new one is healthy. Close the server on SIGTERM so requests in flight can finish:

const server = app.listen(process.env.PORT || 3000);
process.on("SIGTERM", () => server.close(() => process.exit(0)));

1. Sign in with GitHub and install the EthioDeploy app on the repo.
2. Click “New Project” and pick the repo.
3. Watch the build in the dashboard. When the health check passes, your app is live at <project-slug>.ethiodeploy.com. Every push to the default branch redeploys, and the old version keeps serving until the new one is healthy.