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CodeCrafters @codecraftersio
Joined February 2020
  • Tweets 99
  • Following 3
  • Followers 7,370
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CodeCrafters
@codecraftersio
Feb 7
Could you build Claude Code yourself? We’re betting you can. Introducing our newest challenge: Build Your Own Claude Code app.codecrafters.io/courses/… 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.
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CodeCrafters retweeted
Sarup Banskota
@sarupbanskota
May 8
An extraordinary day. Our repo is #1 on GitHub by stars. And the first-ever to hit 500k.
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Introducing our new website. Build something you didn't think you could. codecrafters.io

CodeCrafters | Rebuild Redis, Git & SQLite From Scratch

Advanced programming challenges for experienced engineers. Rebuild real production tools like Redis, Git, and SQLite from scratch in your IDE. Used by engineers at Google, OpenAI, and Vercel.

codecrafters.io
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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? ccbench.org/ Does your favourite agent top the rankings?
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Could you build Claude Code yourself? We’re betting you can. Introducing our newest challenge: Build Your Own Claude Code app.codecrafters.io/courses/… 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.
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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.
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Today we're announcing to give $4,000/yr/engineer to the open source projects we depend on. codecrafters.io/blog/oss-ple…

Our OSS Funding Pledge

We're pledging $4,000 per engineer per year to open source. Here's who we're funding, why it matters, and how other small teams can do the same.

codecrafters.io
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CodeCrafters retweeted
Sarup Banskota
@sarupbanskota
21 Sep 2025
Replying to @rauchg
Here’s a master list of ideas github.com/codecrafters-io/b…
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Sarup Banskota
@sarupbanskota
17 Sep 2025
IIT BHU, welcome to the party. We're making CodeCrafters free for all @IITBHU_Varanasi students, staff and alumni.
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You're invited to the underground coding club, UC Berkeley. CodeCrafters is now free for all @UCBerkeley students, alum, and staff. codecrafters.io/berkeley
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Sarup Banskota
@sarupbanskota
22 Aug 2025
We finally got into IIT. Today we're announcing our partnership with @iitroorkee to make CodeCrafters free for its students, staff and alumni. codecrafters.io/iitr Silicon Valley's favourite challenges. Now at IIT Roorkee.
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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. codecrafters.io/nus

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CodeCrafters retweeted
GitHub Projects Community
@GithubProjects
27 Apr 2025
This repository is a compilation of well-written, step-by-step guides for re-creating our favorite technologies from scratch.
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CodeCrafters retweeted
TechCrunch
@TechCrunch
19 Nov 2024
Codecrafters wants to challenge seasoned developers with hard-to-build projects tcrn.ch/49ekcXn

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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: x.com/i/spaces/1OdJrXBVyeyKX
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Join us in our first ever X Spaces session. We're hosting @JoeAverbukh & @stopachka , the founders of @instant_db. Set a reminder here:  x.com/i/spaces/1OdJrXBVyeyKX
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Starting this week. Stay tuned.
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Today we're sharing news about our $1.8M seed fundraise. codecrafters.io/blog/seed

Our $1.8M Seed Fundraise

We raised $1.8M to build the learning platform for experienced developers. Backed by YC and the engineers behind some of the best devtools.

codecrafters.io
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Today, we're joining @getsentry, @convex and others, in going Fair Source. codecrafters.io/blog/fair-so…
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Today, we’re announcing our latest challenge: Build your own Interpreter. app.codecrafters.io/courses/…
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Ultimately, you’ll discover how programming languages work and how code is executed, at a fundamental level. Get started here: app.codecrafters.io/courses/… The challenge is completely free while in beta.

CodeCrafters | Build Your Own Redis, Git & SQLite From Scratch

Advanced programming challenges for experienced engineers. Rebuild real production tools like Redis, Git, and SQLite from scratch in your IDE.

app.codecrafters.io
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For 10 lucky winners, we're giving away a free copy of the physical book. amazon.com/dp/0990582930 RT the main tweet and start the challenge to become eligible.

Crafting Interpreters

Despite using them every day, most software engineers know little about how programming languages are designed and implemented. For many, their only experience with that corner of computer science...

amazon.com
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