Exercism
Practice exercises in over seventy languages where a volunteer mentor reviews your solution and discusses how to improve it. Free code review from a human is genuinely rare.
Platform
Mentorship
Exercism
Ongoing
Beginner
Free
What it is
A free, open source practice platform with tracks in a very large number of languages. You solve an exercise, submit it, and a volunteer mentor reads your code and responds with feedback and a conversation.
Why the mentored track is the valuable part
Practice sites tell you whether your tests pass. They do not tell you that your solution is unidiomatic, or that the language has a construct that would have replaced ten lines. That feedback normally requires colleagues, and people learning alone do not have any. This supplies it at no cost.
How to use it
Pick a language you want to be genuinely good at rather than one you already know, and request mentoring rather than auto completing exercises. The conversations are the product; the exercises are the excuse for them.
Best for: self taught developers with nobody reviewing their code, and anyone learning a new language properly.
Ready to start?
Opens on Exercism in a new tab.
Stuck on something specific?
Writing only gets you so far. If you want an answer to your situation rather than the general case, book a session and we will work through it together. Every session is free; a few slots open each week.
Follow along
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