Product notes
Product updates, new challenges, and improvements, newest first.
LSP support for your Claude Code
Connect your coding agent to language servers to find definitions and references, synchronize edits, and use diagnostics to repair code.
Skills for your Claude Code
A soft release added a Skills extension: load reusable instructions and teach your coding agent new workflows.
Bitmaps for your Redis
Add the Bitmaps extension and work with individual bits inside Redis string values.
Build Redis in Dart
The Redis challenge now supports Dart.
Build Git in Gleam
The Git challenge now supports Gleam.
Build SQLite in PHP
The SQLite challenge now supports PHP.
Build Git in Elixir
The Git challenge now supports Elixir.
Expand parameters in your shell
Implement shell parameter expansion and learn how variable values become command arguments.
Build a DNS Server in PHP
The DNS Server challenge now supports PHP.
Custom commit messages in the CLI
Choose your own commit message when using the CodeCrafters CLI.
Programmable Completion for Shell
Add programmable completion to your shell.
Ruby 4 support
The Ruby track moves to Ruby 4 across its supported challenges.
Reading is good.
Doing is better.
Build your own Claude Code, Shell, or SQLite. Understand what’s underneath.