# Deploy a Fastify API with PostgreSQL to a VPS

Deploy a Fastify API to your own VPS: ox finds server.js, runs node server.js under systemd behind Caddy, and adds PostgreSQL with DATABASE_URL set.

To deploy Fastify to a VPS with ox, add the repo as a project and deploy it, with no Dockerfile and no ox.toml. ox reads `server.js` and `package.json`, runs `npm install`, then starts `node server.js` under systemd behind Caddy with HTTPS, and sets up postgres 18 for it. Run `ox check` in your repo to see the same plan before the first deploy.

**Plan verified, real-server test pending.** The plan below is what `ox check` prints for a minimal Fastify repo in ox's tests. A deploy on a real server is not recorded yet.

ox reads `server.js` and `package.json`, builds the plan on the card, and starts `node server.js` on your server. The cylinders are the services the repo asked for.

## What ox detects in a Fastify repo

This is the plan `ox check` prints for a minimal a Fastify API with PostgreSQL, with no ox.toml. Each row says where its value came from: a file in the repo, or ox's default.

| Field | Value | Source |
| --- | --- | --- |
| `app.start` | `node server.js` | `detected:server.js` |
| `build.install` | `npm install` | `detected:package.json` |
| `tools.node` | `24` | `default` |
| `services.postgres` | `postgres 18 (shared)` | `detected:package.json` |

## The ox.toml for Fastify

None is needed: the plan above comes from the repo alone. Write one to serve your own domain or to change what ox detected. This one passes `ox check` against the same repo: `[app]` keeps the detected start command and build. Once a repo has an ox.toml, ox adds no service itself, so list each one under `[services]`.

ox.toml, optional:

```toml
domains = ["www.example.com"]

[app]

[services]
postgres = {}
```

## Check and deploy Fastify

Add the repo as a project, then check and ship it from a terminal:

Check, deploy and read the logs:

```sh
ox check                                # in the repo: the plan above, offline
ox new <owner/repo> --server <server>  # add the repo as a project
ox deploy <project> --wait              # stream the deploy, exit with its result
ox logs <project> --follow             # the app's own logs
```

## Variables to set for Fastify

None before the first deploy: `ox check` asks for no variable. Add your own on the dashboard's Variables tab or with `ox vars set <project> KEY`.

ox provides these to the app itself: `PORT`, `HOST`, `OX_ENV`, `OX_PROJECT`, `OX_RELEASE`, `OX_DATA_DIR`, `PUBLIC_URL`, `PUBLIC_HOST` and `DATABASE_URL`.

## If the Fastify deploy fails

- `TCP connect to 127.0.0.1:8001 did not answer within 120s: dial tcp 127.0.0.1:8001: connect: connection refused`: The app started but never answered on the port ox gave it. Listen on `127.0.0.1` at `$PORT`; the lines above the message are the app's own output. [More](https://deploywithox.com/docs/troubleshooting#health-check-failed).
- `package.json has no start script, and no web framework ox knows (express, fastify) is a dependency; add a start script or set [app] start`: Give `package.json` a `start` script that runs your server. [More](https://deploywithox.com/docs/guides/node).
- `web of shop on main keeps crashing: systemd restarted it 5 times in the last 10 minutes. The Logs tab shows why.`: The release went live and then kept dying. Read the Logs tab for the error and deploy a fix, or roll back. [More](https://deploywithox.com/docs/troubleshooting#crash-loop).

Your visitors never see a failed deploy: the previous release keeps serving until the new one passes its health check.

## Next steps

- [The Node.js guide](https://deploywithox.com/docs/guides/node): start scripts, migrations, PostgreSQL and Redis.
- [The `[app]` keys](https://deploywithox.com/docs/config#app): start, health check, memory and the rest.
- [Service dashboards](https://deploywithox.com/docs/operate/services): your database's status, size, backups and data.
- [Add a custom domain](https://deploywithox.com/docs/operate/domains) with one A record; Caddy gets the HTTPS certificate.
- [Read the logs](https://deploywithox.com/docs/operate/logs) live, search them, or download them.
- [Set variables and secrets](https://deploywithox.com/docs/operate/variables) on the dashboard or with `ox vars`.

## Fastify FAQ

### Do I need a Dockerfile or an ox.toml to deploy Fastify to a VPS?

No. ox does not use Docker, and `ox check` on a Fastify repo with no ox.toml prints `Ready to deploy.` Write an ox.toml only to change what ox detected.

### What does ox install on the server for Fastify?

Only what the plan names: `node 24` (ox's default). Your app's own dependencies are installed by the build into the release folder, not system-wide.

### Does Fastify need a start script?

Not for ox. With Fastify as a dependency and one `server.js` at the root, ox runs `node server.js`. A `start` script, when you add one, wins.

## Related guides

- [**Hono on Bun**Deploy a Hono API on Bun to your own VPS: ox installs Bun, runs bun install from bun.lock, and starts src/index.ts under systemd behind Caddy.](https://deploywithox.com/docs/guides/hono-bun)
- [**BullMQ worker**Deploy a Node app with a BullMQ queue to your own VPS: ox adds Redis with REDIS_URL set, runs your server, and the [workers] line runs worker.js beside it.](https://deploywithox.com/docs/guides/bullmq-worker)

Every stack ox deploys, and the ones it does not yet, is on the [Stacks page](https://deploywithox.com/docs/guides).

Last updated 2026-10-09. The page as HTML: https://deploywithox.com/docs/guides/fastify