
Modrinth · Minecraft mod
NilKit API
NilKit API provides reusable utilities for mods built around NilLoader, with a particular focus on legacy Minecraft development.
Quick answer
Which NilKit API release matches 1.13.1?
NilKit API 4.1.0 targets 1.2.1, 1.2.2, 1.2.3 with nilloader. Installation on the client is optional. Installation on the dedicated server is optional. No extra mods listed for this file.
Where it goes
Is NilKit API required on the client, server, or both?
Installation on the client is optional. Installation on the dedicated server is optional.
The source marks this as usable on both the client and server.
What else does NilKit API 4.1.0 need?
4.1.0 on 1.13.1. Every mod below is checked against that same setup.
This file does not list any required mods. Do not add a library just because a different file uses it.
This file does not list any required or optional mods.
Before you install it
Add NilKit API without breaking your instance.
Built for NilKit API 4.1.0 on 1.13.1. Pick another file and the loader, install side or required mods may change.
- 01
Stick to this file
Use 4.1.0. It targets 1.2.1, 1.2.2, 1.2.3 with nilloader; another release may have different loader, side or dependency requirements.
- 02
Bring the mods it needs
This file does not list any required mods. Do not add a library just because a different file uses it.
- 03
Put it on the correct side
Installation on the client is optional. Installation on the dedicated server is optional.
- 04
Pick the file you checked
Use the “Get this file” button beside 4.1.0. It opens that exact file at the source.
About this project
What does NilKit API add?
NilKit API
An independent utility API and developer toolkit for mods built with NilLoader.
Important
NilKit is not part of the official NilLoader project and is not required to use NilLoader.
NilLoader is maintained separately at:
https://git.sleeping.town/Nil/NilLoader
NilKit provides reusable APIs and tooling for legacy Minecraft mod development, with a focus on reducing boilerplate around events, reflection, mappings, metadata, networking, and development utilities.
NilKit 4.1.0 targets Java 8 bytecode and does not require a hard runtime link to a specific Minecraft JAR for its core APIs. Minecraft-specific functionality remains dependent on the mappings and structure of the target game version.
Features
Events and lifecycle
- Lightweight event bus
- Cancellable events
- Listener priorities
premain/hijacklifecycle helpers- Typed and annotation-based listeners
Reflection and legacy Minecraft tooling
- Reflection helpers for version-dependent Minecraft code
- SRG/CSRG mapping utilities
- Mapping inspection, reversal, chaining, and lookup
- Integration with the external
MinecraftRemappingmapping repository during development
KDL
NilKit includes a general-purpose KDL parser and writer and can use KDL for richer project/mod metadata.
KDL support is optional. NilKit does not require NilLoader mods to use KDL, and standard NilLoader metadata remains fully supported.
Example:
nilmod {
name "My Mod"
description "Example mod"
authors "Author"
version "1.0.0"
}
entrypoints {
premain "com.example.MyPremain"
hijack "com.example.MyHijack"
}
nilkit {
requires "nilloader" "nilkit"
load_after "nilkit"
icon "assets/mymod/icon.png"
modurl "https://modrinth.com/mod/my-mod"
sourceurl "https://github.com/example/my-mod"
license "MIT"
credits "Author"
}
Networking
- Java NIO client/server utilities
- Packet registry and codecs
- Optional Minecraft-facing network helpers
Developer toolbox
The optional -all.jar also bundles several developer libraries without relocating their public packages:
- Byte Buddy
- GEB
- ClassGraph
- SnakeYAML
The normal NilKit artifact does not require these libraries at runtime.
Gradle
repositories {
maven {
url = uri("https://repo.tamkungz.me")
}
}
dependencies {
implementation "me.tamkungz.nilkit:nilkit:4.1.0"
}
Documentation
Full documentation and development information are available in the GitHub repository:
https://github.com/NilKitAPI/NilKit-API/tree/main/docs
NilLoader
NilKit is designed to complement NilLoader, not replace it.
NilLoader itself, its loading lifecycle, and its upstream development remain separate from NilKit.
License
NilKit is licensed under LGPL-3.0-or-later.
Project description from Modrinth.
Pick your setup
NilKit API by Minecraft version and loader
Choose the version and loader you play, then open the matching release.
26.1.1
1 loader build26.1
1 loader build1.21.11
1 loader build1.21.10
1 loader build1.21.9
1 loader build1.21.8
1 loader build1.21.7
1 loader build1.21.6
1 loader build1.21.5
1 loader build1.21.4
1 loader build1.21.3
1 loader buildShowing the newest 12 of 99 game versions. Older files are in the list below.
Check the dependencies, then try the file in a copied instance before changing a world you care about.
Recent files
NilKit API versions and loaders
4.1.0
NilKit API-4.1.0-all.jar
6 Aug 2026
4.0.0
NilKit API-4.0.0-all.jar
6 Aug 2026
3.0.2
NilLoaderSDK-3.0.2-all.jar
6 Aug 2026
Looking for an older file? The official Modrinth project page is in Resources.