Introducing sphinx-js, a better way to document large JavaScript projects

Until now, there has been no good tool for documenting large JavaScript projects. JSDoc, long the sole contender, has some nice properties:

  • A well-defined set of tags for describing common structures
  • Tooling like the Closure Compiler which hooks into those tags

But the output is always a mere alphabetical list of everything in your project. JSDoc scrambles up and flattens out your functions, leaving new users to infer their relationships and mentally sort them into comprehensible groups. While you can get away with this for tiny libraries, it fails badly for large ones like Fathom, which has complex new concepts to explain. What I wanted for Fathom’s manual was the ability to organize it logically, intersperse explanatory prose with extracted docs, and add entire sections which are nothing but conceptual overview and yet link into the rest of the work.

The Python world has long favored Sphinx, a mature documentation tool with support for many languages and output formats, along with top-notch indexing, glossary generation, search, and cross-referencing. People have written entire books in it. Via plugins, it supports everything from Graphviz diagrams to YouTube videos. However, its JavaScript support has always lacked the ability to extract docs from code.

Now sphinx-js adds that ability, giving JavaScript developers the best of both worlds.