Flow
Luke

A formspec library that automatically positions and sizes elements

Formspec AST
Luke

A library to help other mods interpret formspecs.

PRANG!
Luke

An unofficial port of PRANG!, a 2D arcade-style game.

Cloaking
Luke

Allows admins to become invisible and appear as if they are not in-game at all.

money3
Luke

Adds /money.

advmarkers
Luke

Allows you to create and manage markers/waypoints.

Blueprints
Luke

Allows Minetest players to easily copy+paste nodes.

Stasis
Luke

Allows players to be put in stasis.

HUD FS
Luke

A library to make HUDs from formspecs

Snippets
Luke

A way for admins to run and save Lua snippets.

FS51
Luke

Compatibility layer for formspecs

SSCSM implementation
Luke

A server-sent CSM library.

Valentine's day
Luke

Adds valentine cards

Flow Inspector
Luke

An "inspect element" helper for flow GUIs

Verbana GUI
Luke

A GUI for verbana

flinv
Luke

API to add new inventory tabs which work across different inventory mods

Squill
Luke

A subset of SQL. No complex installation required.