CodeCrafters

Build your own Git, BitTorrent, SQLite from scratch - in Rust, Go, JS, etc.

Develop robust CS fundamentals. Refine your programming judgement & taste.

[CodeCrafters @codecraftersio]

Could you build Claude Code yourself?

We’re betting you can.

Introducing our newest challenge: Build Your Own Claude Code

https://t.co/TMvnHyLn9U

You’ve been treating AI agents like a black box. It’s time to crack the box open. Build a working coding agent step-by-step and discover what’s generally under the hood.

[Sarup Banskota @sarupbanskota]

An extraordinary day.

Our repo is #1 on GitHub by stars.

And the first-ever to hit 500k.

[CodeCrafters @codecraftersio]

Introducing our new website.

Build something you didn't think you could.

https://t.co/Fkfkf3Puvs

[CodeCrafters @codecraftersio]

Is your coding agent really smart or did it just memorize the test answers?

Today we're launching CCBench, a benchmark for evaluating coding agents on small-scale codebases (<10k LoC) that aren't part of LLM training data.

It's designed to answer a simple question: How well do agents perform on tasks that aren't part of public training data?

https://t.co/chvLyBCVVb

Does your favourite agent top the rankings?

[CodeCrafters @codecraftersio]

This challenge is still in beta. So it's free to try!

It's live in 5 languages currently. Support for more languages coming soon.

[CodeCrafters @codecraftersio]

Could you build Claude Code yourself?

We’re betting you can.

Introducing our newest challenge: Build Your Own Claude Code

https://t.co/TMvnHyLn9U

You’ve been treating AI agents like a black box. It’s time to crack the box open. Build a working coding agent step-by-step and discover what’s generally under the hood.

[CodeCrafters @codecraftersio]

Today we're announcing to give $4,000/yr/engineer to the open source projects we depend on.

https://t.co/aul4WA1cAQ

[Sarup Banskota @sarupbanskota]

@rauchg Here’s a master list of ideas

https://t.co/IpH3RpwO2u

[Sarup Banskota @sarupbanskota]

IIT BHU, welcome to the party.

We're making CodeCrafters free for all @IITBHU_Varanasi students, staff and alumni.

[CodeCrafters @codecraftersio]

You're invited to the underground coding club, UC Berkeley.

CodeCrafters is now free for all @UCBerkeley students, alum, and staff.

https://t.co/CMEodEYg3r

[Sarup Banskota @sarupbanskota]

We finally got into IIT.

Today we're announcing our partnership with @iitroorkee to make CodeCrafters free for its students, staff and alumni.

https://t.co/OaYvTb7ykM

Silicon Valley's favourite challenges.

Now at IIT Roorkee.

[CodeCrafters @codecraftersio]

Today we're making CodeCrafters free for students, staff, and alumni of @NUSingapore.

Silicon Valley's favorite coding challenges. Now making its way through Singapore.

https://t.co/xFIdjC7A0S

[GitHub Projects Community @GithubProjects]

This repository is a compilation of well-written, step-by-step guides for re-creating our favorite technologies from scratch.

[TechCrunch @TechCrunch]

Codecrafters wants to challenge seasoned developers with hard-to-build projects https://t.co/Q2VDIC40u4

[CodeCrafters @codecraftersio]

Tune in tomorrow for a Q&A with Joe & Stepan, the founders of @instant_db

Instant is a modern Firebase that makes you productive by giving your front end an easy, real-time database. It is backed by Paul Graham, Greg Brockman, Amjad Masad and many more.

Set a reminder here to speak with Joe & Stepan: https://t.co/QKXK2JdVht

[CodeCrafters @codecraftersio]

Join us in our first ever X Spaces session. We're hosting @JoeAverbukh &amp; @stopachka , the founders of @instant_db.

Set a reminder here:  https://t.co/rS7cvijY4T

[CodeCrafters @codecraftersio]

Starting this week. Stay tuned.

[CodeCrafters @codecraftersio]

Today we're sharing news about our $1.8M seed fundraise.

https://t.co/s5dama3V1M

[CodeCrafters @codecraftersio]

Today, we're joining @getsentry, @convex and others, in going Fair Source.

https://t.co/kwLqG3iMAA

[CodeCrafters @codecraftersio]

For 10 lucky winners, we're giving away a free copy of the physical book. https://t.co/OjipGh5KFc

RT the main tweet and start the challenge to become eligible.

[CodeCrafters @codecraftersio]

Today, we’re announcing our latest challenge: Build your own Interpreter.

https://t.co/6P9qgTTPwF

[CodeCrafters @codecraftersio]

Ultimately, you’ll discover how programming languages work and how code is executed, at a fundamental level.

Get started here:
https://t.co/6P9qgTTPwF

The challenge is completely free while in beta.