Daily Coding is a free, open-source platform for daily coding challenges. Every day there is exactly one challenge, the same for everyone, all year round. The idea is borrowed from Advent of Code: one problem a day builds a habit, a catalogue of thousands does not.

How it works

You solve the challenge in a built-in editor in the browser and run it against automated test cases in an isolated sandbox. Reading today's challenge and running the tests needs no account. Submitting does.

Eleven languages: JavaScript, TypeScript, Python, PHP, Ruby, Java, Go, C++, C#, Rust and Swift.

What a free account adds

- Streaks and points for every challenge you solve

- Levels and achievements as you keep going

- Weekly, monthly and all-time leaderboards

- Everyone else's solutions, once you have submitted your own

Open source

Daily Coding has no ads and is released under the MIT license. Built and run by one person as a side project.

Technologies: Next.js 16, React 19, TypeScript, Tailwind CSS, PostgreSQL, Prisma, Auth.js, Vitest

Infrastructure: Vercel, Neon, Hetzner, Piston

Website: https://daily-coding.dev

Source code: https://github.com/ledo9315/daily-coding