Owl the Engineer

How it actually works

The engineering questions you get asked, and the bugs you actually hit. Drawn, one mechanism at a time, in the order the videos ship.

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Backend

Database connection pooling and PgBouncer: preventing serverless Postgres crashes

How PostgreSQL process concurrency causes connection exhaustion, and how PgBouncer transaction pooling enables 10,000+ serverless functions to share 50 database sockets.

13 Oct 2026 views0 Read the post →

System design

Database sharding vs partitioning: scaling past one server

When a table grows past 500 million rows, partitioning keeps query plans fast on one server while sharding scales writes across a cluster at the cost of ACID.

9 Oct 2026 views2 Read the post →