Gitea is a self-hosted Git service providing a full DevOps platform including repository hosting, issue tracking, pull requests, wiki, CI/CD (Actions), package registry, and more. The architecture is a monolithic Go web application with a Vue.js frontend, using a SQL database (MySQL, PostgreSQL, SQLite, MSSQL) and supporting various storage backends (local, S3, Azure). Key entry points are the web server (port 3000), SSH server (port 22), and CLI commands for administration. Data flows involve Git operations, webhook notifications, and background job queues. External dependencies include Git, a database, and optional services like Redis, Elasticsearch, and object storage. The codebase is well-structured with extensive testing, but carries some technical debt from a long migration history and dual Git backends.