slowcs

Learn how systems work by building them. Rate limiters, vector databases, B-trees, Raft: we build the systems you use every day, starting from the simplest version and watching a test break it.

Every video follows one design until it fails, explains why it failed, and builds the version that survives. It's how the field got from fixed windows to token buckets, from Paxos to Raft, and it's the part AI can't hand you.

For engineers who already ship and want to understand what's underneath: distributed systems, databases, AI infrastructure, systems programming, security and observability.

New videos every Thursday. Build along on slowcs.com, where Cohort 01 boards in January 2027.