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

JWT vs. PASETO: why security teams are retiring JSON Web Tokens

How algorithm negotiation and ciphersuite confusion create critical security vulnerabilities in JWTs, and how PASETO v4 enforces modern cryptographic safety by default.

15 Oct 2026 views0 Read the post →

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

Direct S3 presigned uploads: avoiding the API backend bottleneck

How to eliminate heavy file upload traffic from application servers by using AWS S3 Presigned URLs and asynchronous serverless event processing.

12 Oct 2026 views0 Read the post →

Backend

WebSockets vs. SSE vs. Webhooks: choosing the right real-time architecture

A deep dive comparing full-duplex WebSockets, unidirectional Server-Sent Events (SSE), and asynchronous Webhook callbacks for modern web systems.

11 Oct 2026 views0 Read the post →