High level design notes

System design problems worked end to end — the design, and the places it got picked apart. Everything else I write lives on my personal blog.

Designs

• WhatsApp architecture — how messages reach offline users.
• Fan-out reminder messaging system — scheduling a reminder and delivering it to ten thousand recipients within a second.
• Live location tracking system — current position, history and "who is near me".
• Top-N movie recommendation system — outline only so far.

Case Studies

Engineering blog posts from big companies, dissected. Nothing here yet.

Research Papers

Research paper summaries. Nothing here yet.

Databases

• Locking and isolation levels in Postgres — isolation levels, row locks, and not selling seat 42 twice.