Formspec AST by luk3yx
A library to help other mods interpret formspecs.
Flow Formspec Collection
A collection by lazerbeak12345
A collection of tools for using flow formspecs
Not officially associated with flow
Packages
Debug by LMD
Debugging on steroids
Flow Extras by lazerbeak12345
An experimental collection of extra widgets for flow
Flow Inspector by luk3yx
An "inspect element" helper for flow GUIs
Flow by luk3yx
A formspec library that automatically positions and sizes elements