Primitives Functions
Functions API
Backend endpoints for your frontend. Deploy code, trigger via HTTP, queue, or cron — zero servers to manage.
Quickstart
Create, deploy, and invoke a function in minutes.
1. Create a function
Register your function with a name and runtime.
POST https://api.rocketstack.dev/functions
Content-Type: multipart/form-data
name=my-handler, runtime=nodejs20.x, handler=index.handler, code=@dist.zip2. Deploy code
Upload a zip bundle with your function code.
POST https://api.rocketstack.dev/functions/fn_123/code
Content-Type: multipart/form-data
code=@dist.zip3. Invoke
Call your function via HTTP with any payload.
POST https://api.rocketstack.dev/functions/fn_123/invoke
Authorization: Bearer YOUR_API_KEY
{ "event": "user.signup", "userId": "usr_789" }Triggers
Multiple ways to invoke your functions.
HTTP Queue Scheduler Cron Your function URL
HTTP
Call your function directly via its unique URL. Pass JSON payloads, headers, and query params.
Queue
Use your function URL as a webhook target. Process messages asynchronously with retries.
Scheduler
Schedule one-time or recurring invocations. We call your function at the specified time.
Cron
Trigger your function on a cron schedule. Perfect for daily reports, cleanup jobs, and syncs.
Limits & Quotas
Generous defaults, adjustable on request.
| Resource | Limit |
|---|---|
| Execution timeout | 60 seconds (default), up to 15 minutes |
| Memory | 128 MB – 3 GB |
| Bundle size | 50 MB compressed, 250 MB uncompressed |
| Concurrent executions | 1,000 (soft limit) |
| Request/response payload | 6 MB |
Authentication
Secure your functions with API keys and optional JWT verification.
API Key
All management API calls require your RocketStack API key in the Authorization header.
Authorization: Bearer YOUR_API_KEYJWT Verification (optional)
Enable JWT verification on your function to validate incoming requests from your frontend.
PATCH https://api.rocketstack.dev/functions/fn_123
{ "auth": { "jwt": { "issuer": "https://..." } } }Ready to deploy your first function?
Get your API key and start building in minutes.