Coding education today is scattered across too many places. A student trying to master Data Structures and Algorithms ends up juggling Leet code for practice, YouTube for concepts, a different tool for mock interviews, and something else again for competitive contests. None of these talk to each other. Motivation drops fast in that kind of fragmented setup, and the dropout rate from structured learning is something most platforms quietly ignore. Codash was built to fix that. It brings DSA practice, game-based algorithm visualisation, real-time coding battles, AI-assisted debugging, mock interviews, and a GitHub- integrated portfolio system together into one platform. The AI layer runs on the Gemini API and provides live code explanation, error detection, optimisation hints, and interview scoring. Matchmaking for 1v1 battles and tournaments uses an ELO-rating model to keep competition meaningful. A coin-based reward economy ties performance to tangible incentives. The system is built on a microservices backend with Node.js, MySQL, Firebase Firestore for real-time features, Redis for caching, and AWS S3 for storage, with React.js and Flutter on the frontend. Testing across all core modules showed that interactive and gamified learning significantly improved user engagement and completion compared to text-only approaches. The platform also aggregates live hackathon listings and supports a peer notes marketplace. This paper describes the architecture, design decisions, and evaluation of Codash as a unified career and learning ecosystem for developers.

KEYWORDS: Gamification, Data Structures and Algorithms, Competitive Programming, AI Coding Assistant, Microservices Architecture, ELO Rating, Mock Interviews, Real-Time Battles, Developer Platform, EdTech