sql.js is a port of SQLite to Webassembly, by compiling the SQLite C code with Emscripten. It uses a virtual database file stored in memory, and thus doesn't persist the changes made to the database. However, it allows you to import any existing sqlite file, and to export the created database as a JavaScript typed array.

There are no C bindings or node-gyp compilation here, sql.js is a simple JavaScript file, that can be used like any traditional JavaScript library. If you are building a native application in JavaScript (using Electron for instance), or are working in node.js, you will likely prefer to use a native binding of SQLite to JavaScript.

SQLite is public domain, sql.js is MIT licensed.

Sql.js predates WebAssembly, and thus started as an asm.js project. It still supports asm.js for backwards compatibility.