Jint is a high-performance JavaScript interpreter for .NET, implementing the full ECMAScript specification (ES2025+) with extensive Web API support (Fetch, Streams, Crypto, Encoding, Workers, etc.) and a headless browser automation layer. The core engine provides a rich embedding API with CLR interop, module loading, execution constraints, and debugging via the Chrome DevTools Protocol. The architecture is modular: the engine itself is a library (Jint), with separate packages for DevTools debugging (Jint.DevTools), browser automation (Jint.Browser), and source generators for efficient interop (Jint.SourceGenerators). The codebase is exceptionally well-tested with thousands of unit tests, Web Platform Tests (WPT), and Test262 conformance tests, plus a comprehensive benchmark suite. It is used in production by projects like RavenDB, EventStore, and OrchardCore as an embedded scripting engine.