Build Your Own
Don't just use the machinery — build it. Each track constructs a real piece of infrastructure stage by stage, with your code running against a test harness right in the browser.
Build Your Own Database
4 stages · 100 min · javascriptBuild an LSM-tree storage engine — the design inside RocksDB, Cassandra, and LevelDB — stage by stage, in your browser. Your code runs against a real test harness; each stage adds the next layer a production engine needs.
Build Your Own HTTP Server
4 stages · 95 min · javascriptHTTP is just text over a socket — until you have to parse it yourself. Build the core of a real HTTP/1.1 server: request parsing, routing with path parameters, correct response framing, and pipelined connections with keep-alive. After this track, load balancers and gateways stop being magic boxes.