I've been watching this space closely and have been on the lookout for new releases. Besides "Building Git", there is also "Building a Debugger"[0], "Writing a C compiler"[1], "Crafting Interpreters"[2], "The Raytracer Challenge"[3], and a few others that I can't vouch for as they appear to be low-quality compared to the ones I listed out.
The potential for technical authors in this space is enormous.
But can you run it on their platform? NO, you need to run it on your own machine which takes a bit of work. And we have over 80 courses waaay over whatever codecrafters has
I kept noticing that most "learn to code" content is tutorials you copy-paste, so I never had to actually understand why anything worked. I built this to flip that: each lesson gives you a real spec (e.g. implement the Redis SET/GET protocol) and you write the code yourself, then it actually runs against tests. Right now there are 80+ of these "build X from scratch" courses — Redis, a database, Git, a compiler, a container runtime, a raft KV store, etc. — across Python, Go, Rust, C, C++, and others. Would love feedback, especially on where the early lessons feel too hand-holdy or too sparse.
I've helped people get into programming face to face and also in a site I liked called exercism which also had a multi language track unit test passing style which I really value and it was purely command line, and I can't stress enough how important the command line is for me for people who want to dabble. Nowadays it's easier to get people into the command line because of Claude/codex.
I only have browsed your site from a phone and looks interesting but I wanted to ask if you had particular insights around getting people to approach learning, design through tests, breaking down problems, without having someone to guide them. Have you had a chance to observe people using your tool and adjust or it's been mostly dog fooding something you would've loved to have.
I've also trained over 100 students in Python back in 2021, when Python was often looked down upon in academia for not being a low-level language. My belief has always been that if someone learns one programming language properly, they can pick up another in no time.I've seen beginners spend months going through 300-video YouTube playlists just to learn JavaScript. People don't need 300 videos to learn a programming language they just need to understand the fundamentals and build projects.
This project, however, is aimed at people who already know a programming language but want to understand what goes on behind the scenes of popular software: how it's designed, why certain architectural decisions are made, and what things to avoid.
Why waste time memorizing arcane flags when you can spend that time actually building things? Frankly I still check man pages for things like tar all the time and I’ve been using linux for over a decade. It becomes less of a fun learning activity and more of a chore when every tool has a hundred different invocations to memorize.
* I didn't see any AI mention, was it entirely built by humans without AI ?
* Were will the tests run ? Your servers or the user machines ? If on your servers, how do you plan to cover the costs if you don't charge for the service ?
* Will you accept contrbutions to the teaching material? How can other people contribute to the teaching material ? What is the AI policy for contributors ?
1. We have temporarily removed it due to abuse (people are sending their own project code through it).
2. Tests are run on our dedicated server. I had some spare servers that we bought for our other platform echoed. gg
3. Will you accept contributions to the teaching material? ofc we would. I am also thinking of open-sourcing the project
4. What is the AI policy for contributors? You can use AI(we also used it), but the quality of the course, should match the rest of the courses
So what's the long term plan? If tests require a bunch of ram, scaling costs seem at odds with "Free Forever". Will you eventually have a pay walled tier? Or will you seek donations to pay for infrastructure or...
I like the idea of a community FOSS or source available offering, I have a lovely pile of ram from the before times (when it didn't cost an arm and a leg).
There's a book about doing this with Git. I wonder how much of the content is cribbed from sources like that, laundered through LLMs.
https://shop.jcoglan.com/building-git/
I've been watching this space closely and have been on the lookout for new releases. Besides "Building Git", there is also "Building a Debugger"[0], "Writing a C compiler"[1], "Crafting Interpreters"[2], "The Raytracer Challenge"[3], and a few others that I can't vouch for as they appear to be low-quality compared to the ones I listed out.
The potential for technical authors in this space is enormous.
[0]: https://nostarch.com/building-a-debugger
[1]: https://nostarch.com/writing-c-compiler
[2]: https://craftinginterpreters.com/
[3]: http://raytracerchallenge.com/
I had a similar suspicion, though I thought the source material was from DAS.
https://www.destroyallsoftware.com/screencasts/catalog
How does this differ from codecrafters.io?
its free
Are we the product?
How can you be the PRODUCT when we have only 500 users? WE are NO GOOGLE my friend. BTW you can use guest mode if feel like you dont want to singup
And entirely AI generated
coauthored by compiler
All the codecrafters content is available on Github too, for free.
This I didn't know, thank you for that! "Build a selfhosted codecrafters" might be a fun meta "build an X"
But can you run it on their platform? NO, you need to run it on your own machine which takes a bit of work. And we have over 80 courses waaay over whatever codecrafters has
I'd rather have something I can tinker with on my own machine, thank you very much
I respect your opinion too.
Signing up is throwing `rate limit exceeded, please try again later`
bots are hitting tons of endpoints bro. You can keep using the platform as guest
This bro thing is so disrespectful.
Looks a lot like CodeCrafters, except it's free. Was it built by humans or AI?
a dafor of things are throwing errors, but good initiative
I kept noticing that most "learn to code" content is tutorials you copy-paste, so I never had to actually understand why anything worked. I built this to flip that: each lesson gives you a real spec (e.g. implement the Redis SET/GET protocol) and you write the code yourself, then it actually runs against tests. Right now there are 80+ of these "build X from scratch" courses — Redis, a database, Git, a compiler, a container runtime, a raft KV store, etc. — across Python, Go, Rust, C, C++, and others. Would love feedback, especially on where the early lessons feel too hand-holdy or too sparse.
I've helped people get into programming face to face and also in a site I liked called exercism which also had a multi language track unit test passing style which I really value and it was purely command line, and I can't stress enough how important the command line is for me for people who want to dabble. Nowadays it's easier to get people into the command line because of Claude/codex.
I only have browsed your site from a phone and looks interesting but I wanted to ask if you had particular insights around getting people to approach learning, design through tests, breaking down problems, without having someone to guide them. Have you had a chance to observe people using your tool and adjust or it's been mostly dog fooding something you would've loved to have.
I've also trained over 100 students in Python back in 2021, when Python was often looked down upon in academia for not being a low-level language. My belief has always been that if someone learns one programming language properly, they can pick up another in no time.I've seen beginners spend months going through 300-video YouTube playlists just to learn JavaScript. People don't need 300 videos to learn a programming language they just need to understand the fundamentals and build projects.
This project, however, is aimed at people who already know a programming language but want to understand what goes on behind the scenes of popular software: how it's designed, why certain architectural decisions are made, and what things to avoid.
Oh that’s really interesting, I never considered that people using Claude has probably made the command line easier to learn.
Or made it easier to not learn. Why memories arcane flags to tar when you can just ask AI to "deal with it"?
Why waste time memorizing arcane flags when you can spend that time actually building things? Frankly I still check man pages for things like tar all the time and I’ve been using linux for over a decade. It becomes less of a fun learning activity and more of a chore when every tool has a hundred different invocations to memorize.
First impression - looks great. Congrats.
I have couple of questions:
* I didn't see any AI mention, was it entirely built by humans without AI ?
* Were will the tests run ? Your servers or the user machines ? If on your servers, how do you plan to cover the costs if you don't charge for the service ?
* Will you accept contrbutions to the teaching material? How can other people contribute to the teaching material ? What is the AI policy for contributors ?
1. We have temporarily removed it due to abuse (people are sending their own project code through it). 2. Tests are run on our dedicated server. I had some spare servers that we bought for our other platform echoed. gg 3. Will you accept contributions to the teaching material? ofc we would. I am also thinking of open-sourcing the project 4. What is the AI policy for contributors? You can use AI(we also used it), but the quality of the course, should match the rest of the courses
Is this going to remain free? I´d love an open source project like this where I could run the tests in my own machine.
Unfortunately, I dont think you can run the tests on your own machine.Tests run on jude0, which takes about 20 GB of RAM to run
So what's the long term plan? If tests require a bunch of ram, scaling costs seem at odds with "Free Forever". Will you eventually have a pay walled tier? Or will you seek donations to pay for infrastructure or...
I like the idea of a community FOSS or source available offering, I have a lovely pile of ram from the before times (when it didn't cost an arm and a leg).