Smart Vector Table
Noodlemire

API that adds a way to create tables indexed by 3D Vectors.

Archaeology
SkyBuilder1717

Adds an looting and API in archaeologing

persistent_monoids
fluxionary

player_monoids that persist between player sessions and server restarts/crashes.

Power Rangers Modpack
LC Creations

Adds power rangers and an API to create your own.

Pova
TenPlus1

Gives mod makers a set of functions to safely apply player physics overrides.

Archipelago Library
Warr1024

Archipelago multi-world randomizer integration library

Intllib
kaeza

Internationalization library.

HTML to Luanti Hypertext
1F616EMO

Convert HTML to Luanti Hypertext for formspecs

Function Delayer
Hybrid Dog

Allows executing functions after a delay to reduce possible lag (EDD scheduler?)

Mobs Effects
SFENCE

Provides predefined attribute effects without apply logic for mobs based on Mobs Redo API, modifying movement, combat, and behavior attributes

Prop Hunt Modpack
Jo5629_

Transform into nodes and with a minigame.

Elepower
IcyDiamond

A wide variety of useful machines

Metatable Metamethods Fixes + Customization
TPH

Attempts to fix issues with metamethods for Lua 5.1 as well as adding new ones + custom functions

Geodes
AwesomeDragon97

Adds amethyst geodes and an API for making custom geodes.

Guidebook Library
mt-mods

A library for registering functional in-game documentation 'guidebooks'.

Entity Control Function Library
Noodlemire

Adds functions to override and unregister entities.

Mana
Wuzzy

Adds a mana attribute to players, can be used as energy source for magical items, etc.

Weapons API
Stix

Adds an API to easily register custom weapons

music modpack
mt-mods

Music modpack with API for easy in-game music playback and custom track registration.

Moblib
LMD

Low-level high-performance entity library

Random Messages
1F616EMO

Register random announcements

MQTT Client Library
Tuxilio

A mod for MQTT communication

LEEF math (CPML)
fatalerror420

Integrates CPML library from the Love framework community into Luanti

Matrix Math Library
entuland

A wrapper around the Lua Matrix library to make it available to other mods

SkillsFramework
domtron vox

SkillsFramework provides an API for creating and managing skills.

mtzip
BuckarooBanzai

zip-library

toolcap_monoids
fluxionary

an API to allow multiple sources to apply changes to a tools's capabilities.

Cellestial Game
LMD

Game of Life in three dimensions.

Commodity market
FaceDeer

Provides API support for various in-world commodity markets

DeltaTime
SkyBuilder1717

Adds deltatime API

In the Fog
Jo5629_

Herobrine has entered your world.

Guns4d (library)
fatalerror420

Adds a library for 3d guns

Lockout
ApolloX

Late-stage Security for Servers

FakeLib
OgelGames

Fake userdata library

City Block II
sorcerykid

Disables use of water and lava buckets within a designated area

balanced diet
fluxionary

api for specifying multiple dimensions to eating

Flow Extras
lazerbeak12345

An experimental collection of extra widget APIs for flow

Vote
rubenwardy

Adds an API to allow players to vote

anarchy
solsword

Anarchy PCG library (see https://cs.wellesley.edu/~pmwh/anarchy/lua/ w/ docs at https://cs.wellesley.edu/~pmwh/anarchy/lua/docs32/index.html)

aSignals
Sumi

Signal event bus API including SIGNAL, LISTEN and CONDITIONAL functions