ModsFinder

Marrow

by naomi

Marrow is a library that bundles the Arrow functional programming libraries for Kotlin and gives mods access to the Arrow project within Minecraft.

FabricForgeNeoForgeClient or server, optionalApache License 2.0Open source1.20.1 – 1.21.8

What it does

Marrow packages the arrow-kt libraries so that mods built on Kotlin can call them without shipping their own copy. Developers who write functional-style code for Minecraft can rely on Marrow as the shared source for those types and helpers, and each release is built for a single set of game versions across Fabric, Forge and NeoForge.

Players do not interact with Marrow directly, since it adds no blocks, items or screens. It only needs to be present when another mod depends on it. It works on either side, and neither needs it, so it can be installed on a client, a server, both or neither, while the mod that uses it decides where it has to run.

Files exist for 15 release versions 1.20.1 – 1.21.8, and the latest Fabric, Forge and NeoForge builds are all 2.1.2 for 1.21.8. The code is released under the Apache License 2.0, and the source code, issue tracker and wiki are public.

Key features

  1. Bundled Arrow libraries

    The arrow-kt libraries ship inside Marrow, so dependent mods do not need to include them separately.

  2. Access to the Arrow project

    Mods can use the Arrow project's functional types and utilities from inside Minecraft through this single library.

  3. Multi-loader builds

    One library version is published for Fabric, Forge and NeoForge with matching file names, such as 2.1.2-forge.

  4. Public source and tracker

    The source code, an issue tracker and a wiki are linked from the project page for anyone reading or contributing.

Compatibility

Latest build for each game version and loader.

1.21.x9 of 9 versions with builds
1.21.82.1.2-fabric2.1.2-forge2.1.2-neoforge
1.21.72.1.2-fabric2.1.2-forge2.1.2-neoforge
1.21.62.1.2-fabric2.1.2-forge2.1.2-neoforge
1.21.52.1.2-fabric2.1.2-forge2.1.2-neoforge
1.21.42.1.2-fabric2.1.2-forge2.1.2-neoforge
1.21.32.1.2-fabric2.1.2-forge2.1.2-neoforge
1.21.22.1.2-fabric2.1.2-forge2.1.2-neoforge
1.21.12.1.2-fabric2.1.2-forge2.1.2-neoforge
1.212.1.2-fabric2.1.2-forge2.1.2-neoforge
1.20.x6 of 6 versions with builds
1.20.62.1.2-fabric2.1.2-forge2.1.2-neoforge
1.20.52.1.2-fabric2.1.2-forge2.1.2-neoforge
1.20.42.1.2-fabric2.1.2-forge2.1.2-neoforge
1.20.32.1.2-fabric2.1.2-forgeNot available
1.20.22.1.2-fabric2.1.2-forgeNot available
1.20.12.1.2-fabric2.1.2-forgeNot available
ReleaseBetaAlphaNot available

Only full game releases are shown. This mod publishes no snapshot builds.

Use cases

Who it’s for: Mod developers who write in Kotlin and want the Arrow libraries available in Minecraft. Players who only install finished mods usually do not need Marrow unless one of those mods requires it.

How it compares

Full comparison

Silk is a Fabric library under the GNU General Public License v3.0 only, open source, for 1.16.5 – 26.3, with a different purpose. Turne off arrow is server-side only under the MIT License, not open source, and covers Fabric, Forge and NeoForge for 1.12.2 – 1.21.10.

ModLoadersGame versionsEnvironmentUpdated
MarrowFabric, Forge and NeoForge1.20.1 – 1.21.8Client or server, optional2025-07-17
SilkFabric1.16.5 – 26.3Client or server, optional2026-09-28
Turne off arrowFabric, Forge and NeoForge1.12.2 – 1.21.10Server-side only2026-02-23

Questions

Which loaders does Marrow support?

Fabric, Forge and NeoForge. The latest file for each is 2.1.2 for 1.21.8, published on 2025-07-16 for Fabric and 2025-07-17 for Forge and NeoForge.

Does Marrow add gameplay content?

No. It provides library code for other mods, and its feature list is limited to the bundled Arrow libraries and their access.

In the catalog

Marrow is one of 3,514 Library mods on ModsFinder, and one of 2,348 Library mods for Fabric. 17,695 mods support Minecraft 1.21.8.

Library mods3,514Fabric modsMods for 1.21.817,695

More from naomi

All projects
Incendium Biomes Only1.19 – 1.21.11RPGTitles1.19 – 1.21.1Cobble1.21.2 – 1.21.4Mystcraft: Ages1.20.1Get Pricked!1.19 – 1.20.4Angle Ring1.20.1 – 1.21.6

Similar mods

Fabric API1.14 – 26.3Cloth Config API1.14 – 26.3YetAnotherConfigLib (YACL)1.19 – 26.3Architectury API1.16.5 – 26.3Just Enough Items (JEI)1.8 – 26.3Geckolib1.12.2 – 26.3

Official listing

Owner
naomi
Published
2025-07-16
Updated on Modrinth
2025-07-17
Facts verified
2026-10-15

Tags

LibraryUtility
Open on ModrinthCompare