Edge Functions

Run TypeScript functions globally at the edge.

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 .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 Supabase Edge Function Examples in GitHub or try these examples: