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Table of Contents
Frequently Asked Questions (from users)
Interoperability
What Minecraft versions does Fabric support?
For most end users, the answer is “snapshot 18w43b and above, releases 1.14 and above”.
For more detailed answers, read below.
Can Fabric run together with Bukkit/Spigot/Paper?
As of now, no. There is some experimental functionality available in Loader's 0.5.0 development branch to run Fabric Loader on top of Paper specifically, but there are many caveats pertaining to Bukkit API's deficiencies. This will probably never be officially supported and should be treated more as a curiosity/special-case scenario.
Can Fabric run together with Forge?
- Fabric does not currently work on top of Forge on modern Minecraft versions.
- It is theoretically possible to create a way to do so - that is to say, there are no known major technical obstacles in accomplishing such.
- There were some experiments and discussions done in this regard (as of 30th June), but nothing usable by end users or mod developers.
The development team does not consider Forge interop a high-priority goal, as our focus is on supporting the Fabric community and its developers and users.
Can Fabric run together with OptiFine?
Not officially. However, unofficial mods exist to faciliate the launching of OptiFine for 1.14+ on Fabric. Your mileage may vary, however.
Can Fabric run on older Minecraft versions?
In theory, there is nothing stopping you from running Fabric's mod loader on older versions of Minecraft, all the way down to c0.0.11a. However, mappings don't yet exist for those versions - as such, making mods is made… a tad more complicated.
Can Fabric run on older Minecraft versions with mods?
Yes! Generally, all JAR mods (such as old versions of OptiFine, or Better Than Wolves) should work fine, and allow the same degree of moddability you'd get with an unmodded version of Minecraft. However, there are some special notes:
For most pre-1.13 mod loaders, you must enable compatibility mode in Fabric Loader, by adding the JVM flag -Dfabric.loader.useCompatibilityClassLoader=true.
With regards to running Minecraft Forge:
- 1.6 ~ 1.12.2: While Fabric used to run on top of LaunchWrapper, this functionality is currently unmaintained and in need of rework.
- 1.3.1 ~ 1.5.2: Not currently planned.
- 1.2.5 and below: Functional, just like ModLoader.
With regards to running ModLoader: No known problems.