CodeCrafters CodeCrafters

Challenges

New here? Start here to learn how challenges work.
Build your own BitTorrent
Build your own BitTorrent
Learn about .torrent files, the BitTorrent Peer Protocol and more
11 stages
Start
Build your own Redis
Build your own Redis
Learn about TCP servers, the Redis protocol and more
44 stages
Start
Build your own HTTP server
Build your own HTTP server
Learn about TCP servers, the HTTP protocol and more
8 stages
Start
Build your own DNS server
Build your own DNS server
Learn about the DNS protocol, DNS record types and more.
8 stages
Start
Build your own Git
Build your own Git
Learn about git objects, plumbing commands and more
7 stages
Start
Build your own grep
Build your own grep
Learn about regex syntax: character classes, quantifiers and more
15 stages
Start
Build your own Docker
Build your own Docker
Learn about kernel namespaces, chroot, the registry API and more
6 stages
Start
Build your own SQLite
Build your own SQLite
Learn about SQL syntax, SQLite's file format, B-trees and more
9 stages
Start

Language Tracks

Go
Go
108 stages
Start
Rust
Rust
108 stages
Start
Python
Python
108 stages
Start
C++
C++
BETA
102 stages
Start
JavaScript
JavaScript
BETA
102 stages
Start
Java
Java
BETA
87 stages
Start
Haskell
Haskell
BETA
85 stages
Start
C#
C#
BETA
80 stages
Start
Ruby
Ruby
BETA
77 stages
Start
C
C
BETA
77 stages
Start
Elixir
Elixir
BETA
55 stages
Start
PHP
PHP
BETA
50 stages
Start
Clojure
Clojure
BETA
44 stages
Start
Crystal
Crystal
BETA
44 stages
Start
Zig
Zig
BETA
20 stages
Start
Kotlin
Kotlin
BETA
11 stages
Start
Nim
Nim
BETA
6 stages
Start