June 14, 20261 min read
Scaling Next.js with Supabase Connection Pools & PgBouncer
Learn how to optimize your serverless backend connections, resolve connection exhaustion, and leverage transaction pooling.
Connection Exhaustion in Serverless Environments
Serverless architectures like Next.js API routes or Vercel functions scale horizontally by spawning new server instances dynamically. However, since each instance opens its own connection to the PostgreSQL database, connection limits are quickly reached during high traffic spikes.
To solve this, we leverage PgBouncer with Supabase:
- Session Pooling: Keeps DB connections open for the duration of the client session.
- Transaction Pooling: The most aggressive option, reusing connections between SQL transactions.
In this guide, we walk through how to configure Prisma schema with custom connection URLs to direct traffic to pgBouncer port 6543, saving database resources and boosting API performance.