Legacy Fabric API

The legacy fabric version of the fabric api.

81.1K Downloads

legacy-fabricornithelibrary

About this Mod

Legacy Fabric API is the core library for the most common hooks and inter compatibility measures utilized by mods using the Legacy Fabric toolchain.

More information and full installation instructions can be found on the Legacy Fabric website and support can be found on the Legacy Fabric discord server.

This is SEPARATE from the Fabric loader! You need both for most mods!

Join our discord server for help: https://discord.gg/yBTpRXe

Join us on #legacyfabric on irc.esper.net

Available Versions

Legacy Fabric API 1.18.3release

MC 1.3, 1.3.1, 1.3.2, 1.4, 1.4.1, 1.4.2, 1.4.3, 1.4.4, 1.4.5, 1.4.6, 1.4.7, 1.5, 1.5.1, 13w16a, 13w16b, 1.5.2, 1.6, 1.6.1, 1.6.2, 13w36a, 13w36b, 13w37a, 1.6.3, 13w37b, 1.6.4, 1.7, 1.7.1, 1.7.2, 13w47a, 13w47b, 13w47c, 13w47d, 13w47e, 13w48a, 13w48b, 13w49a, 1.7.3, 1.7.4, 14w02a, 14w02b, 14w02c, 14w03a, 14w03b, 14w04a, 14w04b, 14w05a, 14w05b, 14w06a, 14w06b, 14w07a, 1.7.5, 14w08a, 14w10a, 14w10b, 14w10c, 1.7.6-pre1, 1.7.6-pre2, 14w11a, 1.7.6, 1.7.7, 1.7.8, 1.7.9, 14w11b, 14w17a, 14w18a, 14w18b, 14w19a, 1.7.10-pre1, 1.7.10-pre2, 1.7.10-pre3, 1.7.10-pre4, 1.7.10, 1.8, 1.8.1-pre1, 1.8.1-pre2, 1.8.1-pre3, 1.8.1-pre4, 1.8.1-pre5, 1.8.1, 1.8.2-pre1, 1.8.2-pre2, 1.8.2-pre3, 1.8.2-pre4, 1.8.2-pre5, 1.8.2-pre6, 1.8.2-pre7, 1.8.2, 1.8.3, 15w14a, 1.8.4, 1.8.5, 1.8.6, 1.8.7, 1.8.8, 15w31a, 15w31b, 15w31c, 15w32a, 15w32b, 15w32c, 15w33a, 15w33b, 15w33c, 15w34a, 15w34b, 15w34c, 15w34d, 15w35a, 15w35b, 15w35c, 15w35d, 15w35e, 15w36a, 15w36b, 15w36c, 15w36d, 15w37a, 15w38a, 15w38b, 15w39a, 15w39b, 15w39c, 15w40a, 15w40b, 15w41a, 15w41b, 15w42a, 15w43a, 15w43b, 15w43c, 15w44a, 15w44b, 15w45a, 15w46a, 15w47a, 15w47b, 15w47c, 15w49a, 1.8.9, 1.9, 1.9.1-pre1, 1.9.1-pre2, 1.9.1-pre3, 1.9.1, 1.9.2, 1.RV-Pre1, 16w14a, 16w15a, 16w15b, 1.9.3-pre1, 1.9.3-pre2, 1.9.3-pre3, 1.9.3, 1.9.4, 1.10, 1.10.1, 1.10.2, 1.11, 16w50a, 1.11.1, 1.11.2, 1.12, 17w31a, 1.12.1-pre1, 1.12.1, 1.12.2-pre1, 1.12.2-pre2, 1.12.2ornithe

June 14, 2026

Legacy Fabric API 1.18.0release

MC 1.3.2, 1.4.7, 1.5.2, 1.6.4, 1.7.2, 1.7.10, 1.8, 1.8.9, 1.9.4, 1.10.2, 1.11.2, 1.12.2ornithe

June 13, 2026

Legacy Fabric API 1.17.1release

MC 1.3.2, 1.4.7, 1.5.2, 1.6.4, 1.7.10, 1.8, 1.8.9, 1.9.4, 1.10.2, 1.11.2, 1.12.2ornithe

May 31, 2026

Legacy Fabric API 1.13.5release

MC 1.3.2, 1.4.7, 1.5.2, 1.6.4, 1.7.10, 1.8, 1.8.9, 1.9.4, 1.10.2, 1.11.2, 1.12.2legacy-fabric

May 31, 2026

Legacy Fabric API 1.17.0release

MC 1.3.2, 1.4.7, 1.5.2, 1.6.4, 1.7.10, 1.8, 1.8.9, 1.9.4, 1.10.2, 1.11.2, 1.12.2ornithe

May 30, 2026

How to Install Legacy Fabric API on Your Server

Order Server

Order a Minecraft Java server with at least 3 GB RAM (4 GB recommended).

Set legacy-fabric Loader

In the panel under "Egg", select the legacy-fabric loader and matching Minecraft version (1.12.2).

Install Mod

Open the mod browser in the dashboard and search for "Legacy Fabric API". Click "Install" – done! Alternatively, upload the .jar via SFTP to the /mods folder.

Compatibility

Mod Loaders

legacy-fabricornithe

Minecraft Versions

1.12.2, 1.12.2-pre2, 1.12.2-pre1 (+165 more)

Server-side

~ Optional

Recommended RAM

4 GB(min. 3 GB)

Frequently Asked Questions

Legacy Fabric API server crashes on startup – what to do?

Most common cause: wrong legacy-fabric version or insufficient RAM. Check the server log (latest.log) for "OutOfMemoryError" or "Mixin" errors. With Mado Hosting: ensure at least 3 GB RAM is allocated and the loader matches the mod version (1.12.2). You can switch loaders with one click in the panel.

Is Legacy Fabric API compatible with legacy-fabric and ornithe?

Legacy Fabric API officially supports legacy-fabric, ornithe for Minecraft 1.12.2, 1.12.2-pre2, 1.12.2-pre1. The Mado dashboard automatically detects incompatible loader combinations.

Server lagging with Legacy Fabric API – how to optimize performance?

Recommended RAM: 4 GB (per 8 players). Use /spark profiler to check if Legacy Fabric API consumes the most tick time. Common fixes: reduce server view-distance to 8-10, install "performant" or "starlight" as supplementary mods on Forge. With Mado Hosting, your server runs on NVMe SSDs with dedicated CPU cores for minimal latency.