Express site with TLS

Run an Express app in workspace alice, reachable at https://app.example.com with an HTTPS certificate that renews itself.

You need: workspace alice from Getting started, and app.example.com pointed at your machine (or a DNS provider package installed, so expose add points it for you).

1. Add Caddy to the machine

devmachine packages add caddy
devmachine sync

Caddy answers every exposed site and gets its own certificate.

2. Write and start the app

devmachine ssh alice
mkdir app && cd app
npm init -y && npm install express pm2
cat > server.js <<'EOF'
const express = require('express');
const app = express();
app.get('/', (req, res) => res.send('Hello from alice'));
app.listen(3000);
EOF
npx pm2 start server.js --name app

pm2 keeps the app running in the background, even after you log out.

3. Expose the port

Back on your own computer:

devmachine expose add alice 3000 --host app.example.com --publish
devmachine sync

sync writes the Caddy route and gets the certificate for the host.

4. Point the domain, if it was not automatic

If a DNS provider package (hostinger, cloudflare) is installed, expose add already wrote the record — see DNS. Otherwise it printed the record to create by hand at your registrar.

Check it: curl https://app.example.com returns “Hello from alice”, with a valid certificate.

Source: Express — Hello world, pm2 — Quick start