CodeFights

CodeFights was a web-based platform for practicing programming and preparing for technical interviews. It hosted a large catalog of algorithm challenges covering topics such as data structures, graph theory, and dynamic programming. Solutions could be written in multiple programming languages, executed against test cases, and automatically checked for correctness. The site also offered features designed to simulate interview conditions, including real-time coding battles and a game-like arcade progression that rewarded completing sets of problems with levels and badges.

As the platform and its community grew, CodeFights expanded beyond solitary practice to serve broader assessment needs. In later years, the CodeFights brand was renamed CodeSignal, and its content and features were integrated into CodeSignal’s consolidated platform for coding practice, interview preparation, and technical assessments used by individuals as well as employers.

CodeSignal’s offerings include a wide range of practice problems, an online editor with immediate feedback, and company-provided interview kits. The platform also provides standardized coding assessments that employers use as part of hiring processes, outreach for candidate screening, and remote evaluation of programming skills. Through its evolution from CodeFights to CodeSignal, the service positioned itself as both a personal learning resource for developers and a scalable solution for technical recruitment.