By the end of this checkpoint
- Listen for TCP connections on port 4000
- Print whatever raw bytes the server receives
- Stay alive across multiple connections
- Handle more than one connection at the same time
Write a TCP server from scratch using the net package. No HTTP, no parsing, no frameworks. Just a socket that talks.
Verify
Run nc localhost 4000 in two terminals. Both connect, raw bytes print, and the server stays alive.