Battlesnake is described as 'multi-player programming game played by developers all over the world. All you need to play is a live web server that implements the Battlesnake API' and is an website in the Development category. There are more than 10 alternatives to Battlesnake, not only websites but also apps for a variety of platforms, including Windows, Linux, Mac and iPhone. The best alternative is exercism, which is both free and Open Source. Other great sites and apps similar to Battlesnake are HackerRank (Free Personal), Codewars (Freemium), CodinGame (Free) and CheckIO (Free, Open Source).
LeetCode is a platform for learning and improving coding skills with the goal of being fully prepared for programming interviews. Choose problems to solve from categories such as System Design, Algorithms and Database, join code contests and engage in mock interviews.
CodeCombat is an online game that teaches programming to learners as young as 6. Students write code in real programming languages. No experience required! - How much does it cost? There are 110+ FREE levels which cover every concept.
Screeps is a massive multiplayer online real-time strategy game. Each player can create his or her own colony in a single persistent world shared by all the players. Such a colony can mine resources, build units, conquer territory.
CodeSignal is the leading provider of assessments for technical hires. As the creator of the Predictive Coding Score, a measure of a candidates coding skills, CodeSignal provides HR teams with Certified Assessments, Custom Tests, and Live Interviews.
CSSBattle is an online CSS Code Golfing battleground. Here, players from all around the world try to visually replicate "Targets" in smallest possible CSS code and battle it out to get to the top of the leaderboard. Are You Game?