Product notes
Product updates, new challenges, and improvements, newest first.
Build an HTTP server in Elixir
The HTTP server challenge added Elixir support.
Zig for Shell and Interpreter
Zig support expanded to the Shell and Interpreter challenges.
OCaml for Interpreter and Redis, in beta
The OCaml track opened in beta with Interpreter and Redis support.
Dark mode for members
A members-only dark theme initially became available on the main learning pages.
Interpreter: Evaluating Expressions
Evaluate parsed expressions in your interpreter.
Kotlin across the challenge catalog
Kotlin support expanded across all challenges available at the time.
Interpreter: Parsing Expressions
Represent expressions and build the parser for your interpreter.
Build your own Interpreter
Initially released in beta, this challenge covers tokenization, parsing, and expression evaluation in a Lox interpreter.
Refresh your GitHub identity
A profile-settings button let learners sync a changed GitHub username.
Redis transactions
Implement MULTI and EXEC and learn how Redis handles transactions and failures.
More responsive challenge updates
Reduced background delays made challenge-page updates arrive more reliably.
C++ packages across challenges
C++ implementations gained vcpkg dependency support across the catalog.
Reading is good.
Doing is better.
Build your own Claude Code, Shell, or SQLite. Understand what’s underneath.