Squareroot.js code was born out of many years of experience in building WebGL apps. It is written in a pragmatic way - with the goal of getting things done rather than complying to a praticular programming pattern or philosphy. It makes it very flexible, powerful and easy to use, once you get familiar with it.
The first version of this library was created 6 years ago - it was called J3D back then. After that is was re-written from scratch... three times. Each iteration was was built with better understanding of the underlying WebGL API and the mathematics of 2d and 3d rendering.
The structure is loosely based on Unity3d API, including the central concept of 'Transforms' as building blocks. It also features a Unity-to-WebGL exporter that can export meshes and skinned meshes, textures, animations and even entire scenes.