Projects

build real systems from scratch, or sharpen your tools.

18 tasks

Build Your Own
HTTP Server

Build an HTTP server from raw TCP sockets. No frameworks, no libraries - just you and the protocol specification. Understand exactly what happens when browsers talk to servers.

get /api
host: lighthouse
accept: */*
200 ok
content-length: 14
{"ok": true}
raw socket → parsed · routed · served
8 tasks

1 Billion Row
Challenge

Process 1 billion temperature measurements as fast as possible. Start with a working solution, then systematically optimize - I/O, parallelism, parsing, data structures - until you're competing with the best.

naive 187s→ your goal < 5s
19 tasks

SeaChart: Your Own
DNS Resolver

Understand DNS from the ground up by building a recursive resolver. Parse binary protocols, query root servers, follow delegation chains, and implement caching.

1query · root server
12ms
2follow .com ns
28ms
3follow lighthouse ns
9ms
aanswer · 192.0.2.7
+ cache
recursive resolution · binary protocol