Supported frameworks
| Framework | Detected by | Output |
|---|---|---|
| Static HTML | An index.html and no build script | The folder, as is |
| Vite | A Vite dependency | dist |
| Astro | An Astro dependency | dist |
| Next.js | A Next.js dependency | A server bundle plus static assets |
| Other static builds | Choose the preset and set the output directory | Your output directory |
Detection is a starting point. Set the Framework preset, commands and output directory in project settings to override it.
How a build runs
- Fetch the source. From the commit on GitHub, or from your CLI upload.
- Install. Using your lockfile (
npm ciby default, or the install command you set). - Build. Your build command, with your environment variables.
- Publish. The output is hashed and stored. Identical files are shared between deployments, so unchanged assets upload once.
- Start check (server apps only). The server is started and must answer a request before the deployment is marked ready.
Builds have a time limit and memory and CPU limits. If a build runs out, the log says so.
Next.js
Next.js apps are built into a self-contained server bundle. Static pages are served from the edge; server-rendered routes, route handlers and middleware run on a server beside the edge in each region.
- The server starts on the first request and stays warm while production traffic keeps arriving.
- Anything the server prints appears in Runtime Logs.
- Responses are cached at the edge only when your application marks them shareable. See Caching.
The build environment
A build sees only what you gave it: your project's environment variables for that target, plus the standard variables needed to run Node. No platform secrets are ever passed to a build. Builds run in a container as an unprivileged user with a read-only root file system and cannot reach internal networks.
# available during the build
NODE_ENV=production
YOUR_VARIABLES_FROM_THE_DASHBOARD=...See Environment variables and the Security page.
Dependency caching
Installed dependencies are cached per project. The cache is reused when the lockfile, the Node version and the install command are all unchanged, which makes most builds start building almost immediately. Change any of the three and a fresh install runs.
Monorepos
Set the Root directory to the package you want to deploy, for example apps/web. Install, build and the output directory are then relative to it. Import the repository once per package to deploy several apps from it.