SignalDB is a reactive local JavaScript database providing a MongoDB-like interface, first-class TypeScript support, and signal-based reactivity across various frameworks. It's designed with a universal interface, allowing integration with many JavaScript libraries and frameworks like Angular, Solid.js, Preact, and Vue via reactivity adapters. This facilitates real-time data updates, simplifies data management, and ensures rapid query performance. Its schema-less design, in-memory storage, and seamless integration make it a versatile choice for developers.