ForerunnerDB is a NoSQL JavaScript JSON database with a query language based on MongoDB (with some differences) and runs on browsers and Node.js. It is in use in many large production web applications and is transparently used by over 6 million clients. ForerunnerDB is the most advanced, battle-tested and production ready browser-based JSON database system available today. What is ForerunnerDB's Primary Use Case? ForerunnerDB was created primarily to allow web (and mobile web / hybrid) application developers to easily store, query and manipulate JSON data in the browser / mobile app via a simple query language, making handling JSON data significantly easier. ForerunnerDB supports data persistence on both the client (via LocalForage) and in Node.js (by saving and loading JSON data files). If you build advanced web applications with AngularJS or perhaps your own framework or if you are looking to build a server application / API that needs a fast queryable in-memory store with file-based data persistence and a very easy setup (simple installation via NPM and no requirements except Node.js) you will also find ForerunnerDB very useful.