Sounds
AntumDeluge

A set of free sounds & API.

Ranged Weapon Framework (rawf)
LandarVargan

A ranged weapon framework for Minetest

Placeable Buckets for Catching Rainwater
Noodlemire

Allows empty buckets to be placed as nodes in order to collect rainwater.

Named Waypoints
FaceDeer

A library for managing waypoints shown in player HUDs that can be discovered by exploration.

Air Currents (sum)
Sumianvoice

Adds air currents which can push objects and players.

Filled Bottles
EmptyStar

Filled bottles for Minetest Game

Controls
BuckarooBanzai

Utility library for control press/hold/release events

Epic
BuckarooBanzai

Enhanced Programmer for Ingame Control

mod utilities
theFox

Providing some utilities that can be used by other mods.

City Block II
sorcerykid

Disables use of water and lava buckets within a designated area

Discord-Minetest Relay
archfan7411

Mod + external program providing Discord relaying and commands.

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.

Botic Font
Pyrollo

Botic font minetest mod for font API

Polygraph
sorcerykid

Polygraph is a formspec-based charting API, providing a rich set of output parameters and custom rendering hooks within an object-oriented framework.

Name Generator
FaceDeer

A lua library for generating random names based off of rulesets and syllable lists.

Playtime Recorder
Lejo

Use /playtime to get the time you played

SkillsFramework
domtron vox

SkillsFramework provides an API for creating and managing skills.

BeTween Api
_gianpy_

Interpolation functions and a Tween object to make smooth interpolations in huds or anything else you need.

Scarlet
sorcerykid

Scarlet is a thin-wrapper library that simplifies the layout of formspec elements.

futil
fluxionary

flux's utility mod

Player Effects
Wuzzy

Framework for temporary effects for players.

Display Modpack
Pyrollo

Display modpack provides mods with dynamic display (signs, clocks, steles) and api to manage font and display

Appliances API
SFENCE

API for create appliances in other mods powered by technic, mesecons or hand.

Mapblock Lib
BuckarooBanzai

mapblock serialization functions

LootChests Modpack
mt-mods

Modpack adding a lot of various loot containers across the world to be found and providing an API, resources and integrations for other mods

Adaptation lib and mods
SFENCE

Key based adaptation database of items.

Fluid Container API
IcyDiamond

Library for nodes containing fluids

ts_workshop
Thomas-S

API for workshops

Cartographer
Hugues Ross

A mapmaking API. Needs additional mods to function.

ActiveFormspecs
sorcerykid

ActiveFormspecs is a framework that abstracts the builtin formspec API of Minetest

Player Physics API
Wuzzy

This makes it possible for multiple mods to modify player physics (speed, jumping strength, gravity) without conflict.

mtzip
BuckarooBanzai

zip-library

HUD Timers
LMD

A lightweight library for adding hud timers.

moreblocks and stairsplus
fluxionary

adds various blocks to the game

3D Armor Light
AntumDeluge

Wielded Light for 3d_armor

Configuration Panel
sorcerykid

API extension that allows seamless loading of mod configuration at runtime

Panel_lib
Zughy

Library allowing modders to create complex HUDs in an easy way

Natural slopes library
karamel

Library to simply add slopes to regular nodes and include them on map generation and when changing the landscape.

Achievements Lib
Zughy

API to store all your achievements in one place

Documentation System
Wuzzy

A simple in-game documentation system which enables mods to add help entries based on templates.