Level

Welcome!

Level is a community and a collection of Node.js modules for creating transparent databases. A solid set of primitives enable powerful databases to be built in userland. They can be embedded or networked, persistent or transient - in short, tailored to your needs.

At the core of Level are simple key-value stores that follow the characteristics of LevelDB. LevelDB is a key-value store built by Google, used in Google Chrome and many other products. It supports arbitrary byte arrays as both keys and values, singular reads and writes, batched writes and bi-directional iterators. LevelDB sorts entries lexicographically by keys which, when combined with ranged iterators, makes for a very powerful query mechanism.

To bring those concepts to Node.js and other JavaScript runtimes, Level utilizes idiomatic Node.js interfaces like streams, events and buffers. It offers a rich set of data types through encodings and allows for extensions like subleveldown to split a database into evented sections. Underlying stores can be easily swapped to target a wide range of runtime environments. The most common store is leveldown which is a pure C++ binding to LevelDB. Many alternatives are available such as level-js in the browser or memdown for an in-memory store.

The level module is the recommended way to get started. Visit awesome to discover more modules. See our project board to find out what we're working on. If you need help - technical, philosophical or other - feel free to open an issue in community or a more specific repository.

Live Demo

As of level@5, the above code works in Node.js, Electron and browsers!