CodeTrain / About
About CodeTrain
CodeTrain is a Socratic AI coding tutor for engineering teams. It teaches a developer on the codebase they actually work in, and it never writes their code for them.
What the product does
You point CodeTrain at a task, a topic or a repository. It breaks the work into small steps, explains the part you need before you attempt it, and then asks you to write the code. Each step runs. If it does not pass, the step does not advance, and the tutor asks a question instead of handing over the answer. At the end you have a record of which steps you wrote unaided, which is a different thing from a completion percentage.
The reason it works this way is narrow and it is the whole product. An assistant that writes the code produces working code and no new skill. A team that ships code nobody on it can explain has a problem that shows up months later, in review, in an incident, or when the person who prompted the change leaves. CodeTrain is built for the opposite outcome: slower on the first task, and the engineer can do the second one.
Who builds it
CodeTrain is built by Ethan Ludwig, the founder of InferHaven, a research studio for privacy and local-first AI in Michigan, United States. He builds it solo and in the open. InferHaven's other product is Bulkhead, a self-hostable private AI coding server whose source is public on GitHub. The studio publishes each study with its data, code and every raw reply, under open licenses, with a DOI; the first one tested CodeTrain's published tutor rules. CodeTrain is in beta, and every page says so rather than burying it, because a team deciding whether to put their engineers on it deserves to know how young it is.
Three things we will not do
- We will not write the learner's code. The tutor may quote your own code, your run output and the wording of the step, and there is a code guard sitting on top of that rule, so a snippet you could paste and pass with is removed before it reaches you.
- We will not report progress we did not measure. A skill is solid, under review, or being learned, and there is no "not started" state at all: reporting one needs a fixed list of concepts to subtract from, and ours grows out of what you actually do. A receipt with nothing assessable on it says exactly that instead of showing a zero.
- We will not send your prompts or your code to our error tracker. Stack frame locals are switched off at the client rather than filtered somewhere downstream.
The full data handling story is on the security page, and what we collect is in the privacy policy.
Talk to us
Support, sales, security reports and press all have addresses on the contact page. If you want to see the product before you talk to anybody, there is a lesson running on the homepage that needs no account.