Interactive Item API
Jose_ManuelS18

Provides an API to make it easier to implement items' inner workings.

Unified Stamina API
TestificateMods

Provides a universal API for handling different mods that provide a stamina bar

More Triggers
SkyBuilder1717

Adds more triggers for Awards

imfs
Signal_

An immediate-mode, functional, reactive abstraction around Minetest's formspec system.

Archaeology
SkyBuilder1717

Adds an looting and API in archaeologing

TPH's Basic Filesystem
TPH

API for loading files into a basic readable format as well as loading and converting conf files

flinv
Luke

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

Lush
rstcxk

fully featured shell interpreter

AFK Indicator
1F616EMO

API to check player AFK status

Advanced Rangefinder
sorcerykid

Extends the API with search capabilities for entities

Natural Entities
LuantistDork

A lightweight API for spawning random entities

Grenades API
LandarVargan

Adds an API for easily creating grenades

Scripted World Editor
Neuromancer

API that allows you pass in scripting tables to fill a series of shapes of different sizes with different nodes

Phonics Library
Neuromancer

Provides a library for creating Phonics (Learn how to read) mods in different languages.

Advanced Breath and Health APIS
liteninglazer

Creates APIS to allow different players to heal health and allow different players to breathe different items.

Select Item
Wuzzy

Allows other mods to add a simple form to choose a single item.

CSMT Bots (Obsolete)
Logikí

Add bots to your game for training

Priority Queue
Wiz

Associate items with priorities to order them.

FS51
Luke

Compatibility layer for formspecs

Prop Hunt Modpack
Jo5629_

Transform into nodes and with a minigame.

Dialogs
1F616EMO

Dialogs with options

Debugging Console
sorcerykid

Provides an in-game HUD to easily monitor debug output

Complete and Total Lua-Only Inventory Rewrite
Noodlemire

Creates a completely custom inventory system, which doesn't rely at all on any of the usual UserData objects.

CentralAuth
1F616EMO

Player account unification across Luanti servers

color_lib
bookgirl

adds HEX colouring

Cid Music Player
ekl

Plays music

Discrete Player API
Hypernoot

A library for games which attaches players to node grid

group:any
1F616EMO

Item group applied to ALL items for crafting recipes.

Chunk Version
Sumi

Stores the numerical version a chunk was generated, so that other mods may query this.

action queues
fluxionary

provides an API for queuing things for batch processing w/ various ways to specify the batch "size".

DataMiner
sorcerykid

DataMiner is an analytical tool for server operators with a feature-rich API for customized report generation

Pedestals Api
mzel1982

Register your own mesh pedestals.

Nametags2
Logikí

Allow objects had nametags with observers, colors and range

afk_api
fluxionary

an API for registering events which trigger when a player goes AFK or comes back from AFK.

node entity queue
fluxionary

a queue for spreading out the generation of node entities over multiple server steps (smartshops, signs, itemframes, etc).

YAML Config File Library
snowyu

Load or Save YAML config file

Tips
1F616EMO

Send tips to newcomers

GroupLib
rudzik8

General grouping API

Timekeeper
sorcerykid

Timekeeper acts as a centralized dispatcher for all time-sensitive routines

Wield Events
mt-mods

Events for wield item switching