Edge Functions
Globally distributed TypeScript functions.
Edge Functions are server-side TypeScript functions, distributed globally at the edge—close to your users. They can be used for listening to webhooks or integrating your Supabase project with third-parties like Stripe. Edge Functions are developed using Deno, which offers a few benefits to you as a developer:
- It is open source.
- It is portable. Supabase Edge Functions run locally, and on any other Deno-compatible platform (including self-hosted infrastructure).
- It is TypeScript first and supports WASM.
- Edge Functions are globally distributed for low-latency.
How it works
- Request enters an edge gateway (relay) — the gateway routes traffic, handles auth headers/JWT validation, and applies routing/traffic rules.
- Auth & policies are applied — the gateway (or your function) can validate Supabase JWTs, apply rate-limits, and centralize security checks before executing code.
- Edge runtime executes your function — the function runs on a regionally-distributed Edge Runtime node closest to the user for minimal latency.
- Integrations & data access — functions commonly call Supabase APIs (Auth, Postgres, Storage) or third-party APIs. For Postgres, prefer connection strategies suited for edge/serverless environments (see the
connect-to-postgres
guide). - Observability and logs — invocations emit logs and metrics you can explore in the dashboard or downstream monitoring (Sentry, etc.).
- Response returns via the gateway — the gateway forwards the response back to the client and records request metadata.
Quick technical notes
- Runtime: Supabase Edge Runtime (Deno compatible runtime with TypeScript first). Functions are simple
.ts
files that export a handler. - Local dev parity: Use Supabase CLI for a local runtime similar to production for faster iteration (
supabase functions serve
command). - Global deployment: Deploy your Edge Functions via Supabase Dashboard, CLI or MCP.
- Cold starts & concurrency: cold starts are possible — design for short-lived, idempotent operations. Heavy long-running jobs should be moved to background workers.
- Database connections: treat Postgres like a remote, pooled service — use connection pools or serverless-friendly drivers.
- Secrets: store credentials in Supabase project secrets and access them via environment variables.
When to use Edge Functions
- Authenticated or public HTTP endpoints that need low latency.
- Webhook receivers (Stripe, GitHub, etc.).
- On-demand image or Open Graph generation.
- Small AI inference tasks or orchestrating calls to external LLM APIs (like OpenAI)
- Sending transactional emails.
- Building messaging bots for Slack, Discord, etc.
Examples
Check out the Edge Function Examples in our GitHub repository.