Neon API (unofficial showcase)
POST/projects/{project_id}/branches/{branch_id}/functions/{slug}/deployments

Create a function deployment

Creates a deployment for a function on a branch. Supply at least one of zip, environment, or runtime; omitted fields inherit the function's latest version. The first deployment must include zip, and the newest deployment becomes active.

  • IdempotentThe SDK sends Idempotency-Key, so a retried request is only applied once.

3 parameters · 3 body fields
project_idstringrequired
The Neon project ID. Must contain 1–60 lowercase letters, numbers, or hyphens.
branch_idstringrequired
The Neon branch ID. Must contain 1–60 lowercase letters, numbers, or hyphens.
slugstringrequired
The function slug. Must contain 1–20 lowercase letters or numbers.

Multipart form data for a function deployment. Supply at least one field; the first deployment must include zip.

zipstringoptional
Optional ZIP archive of the function source code. Omit to reuse the latest version's bundle (a config-only change). Required for the first deployment of a function. Place `index.mjs` or `index.js` at the archive root, without a containing directory. If both exist, `index.mjs` is loaded. Export a request handler function or an object with a `fetch` method. Use `export default` for ESM or `module.exports` for CommonJS; prefer `index.mjs` for ESM. Upload JavaScript ready to run on Node.js 24. Compile TypeScript before uploading. Bundle dependencies into the entry module, or include the required modules and assets in the archive with their relative paths preserved (including `node_modules` for external packages). Node.js built-in modules do not need to be bundled. The API does not transpile, bundle, or install dependencies. The ZIP is limited to 32 MiB compressed and 128 MiB extracted, with at most 32,768 entries and 64 MiB per file. Bundle large dependency trees to keep the archive small. ZIPs larger than 32 MiB are rejected with HTTP 413 before creating a deployment. The extracted-size, entry-count, and per-file limits are enforced during the asynchronous build; an accepted upload that exceeds them fails the build. For example, a self-contained ESM bundle needs only `index.mjs` at the ZIP root. The Neon CLI bundles source into this layout by default; `neon function deploy --no-bundle` packages a prebuilt directory or an entry file named `index.mjs` or `index.js`.
runtimestringoptional
The function runtime. The only supported value is `nodejs24`.
Allowed:nodejs24
environmentstringoptional
Optional JSON object (a string-to-string map) of environment variables for the deployment, e.g. {"KEY":"VALUE"}. Carried as a JSON-encoded string because multipart form data does not support typed object parts. Values are write-only: they are encrypted at rest, and responses carry only the variable names (the `environment` array), never the values.

2 status codes
201Returns the created deployment, including its ID, status, memory allocation, runtime, creation time, and any environment or error details.
deploymentobjectrequired
defaultGeneral Error. The request may or may not be safe to retry, depending on the HTTP method, response status code, and whether a response was received. - If no response is returned from the API, a network error or timeout likely occurred. - In some cases, the request may have reached the server and been successfully processed, but the response failed to reach the client. As a result, retrying non-idempotent requests can lead to unintended results. The following HTTP methods are considered non-idempotent: `POST`, `PATCH`, `DELETE`, and `PUT`. Retrying these methods is generally **not safe**. The following methods are considered idempotent: `GET`, `HEAD`, and `OPTIONS`. Retrying these methods is **safe** in the event of a network error or timeout. Any request that returns a `503 Service Unavailable` response is always safe to retry. Any request that returns a `423 Locked` response is safe to retry. `423 Locked` indicates that the resource is temporarily locked, for example, due to another operation in progress.
request_idstringoptional
Unique identifier for the request, useful for debugging. You can set this value manually by including an `X-Request-ID` header in the request. If not provided, the value will be generated automatically.
codestringrequired
Machine-readable code classifying the error type. See `message` for a human-readable explanation.
Default:
messagestringrequired
Error message

Error handling

The project_id path parameter and branch_id path parameter must each contain 1–60 lowercase letters, numbers, or hyphens; the slug path parameter must contain 1–20 lowercase letters or numbers. Supply at least one of zip, environment, or runtime; the first deployment requires zip, and runtime must be nodejs24 if provided.