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Migrating From Fabric

While Quilt supports loading Fabric mods, you might want to experience some additional features that Quilt might provide.

To set up a Quilt mod workspace, check the Setup guide.

Notable Differences

Although many things are very similar, there are a few remarkable divergences between Quilt and Fabric mods.

Mod Metadata

Quilt utilizes a quilt.mod.json which is largely different from the fabric.mod.json. More information can be found at the quilt.mod.json specification RFC; Furthermore, a JSON schema for it is also available.

  • The naming convention that official fields naming use is snake_case, instead of camelCase.
  • The structure contains many differences.
    • Most of the fields have been reorganized into objects, such as quilt_loader and minecraft.
    • Information that is meant to be read and shown to humans is now contained under a metadata block.
  • Custom values are not defined in a custom object, instead they are declared in the top-level object.
  • The dependency notation now is able to be represented as an object.

Built-in Entrypoints

  • The game initializers (i.e. ModInitializer, ClientModInitializer, and DedicatedServerModInitializer) have been moved from loader to the base module of Quilt Standard Libraries.
  • Their keys have been altered.
    • ModInitializer: init
    • ClientModInitializer: client_init
    • DedicatedServerModInitializer: server_init
    • PreLaunchEntrypoint: pre_launch
  • Their main methods now contain a ModContainer parameter that represents the mod that declared them.
  • Entrypoints can be declared with a single key-value in the quilt.mod.json instead of an array, if there is only one.

Base API

While not all of Fabric API has been matched by Quilt Standard Libraries, the parts that have been, were improved, besides all the new APIs that were added.

A comparison chart that shows features that are present or absent, between QSL and Fabric API is available at the Quilt Standard Libraries README.

In case there is the need of usage of an API which is present in Fabric API, but not in QSL, it is possible to pull and use Quilted Fabric API, which acts as a bridge between both.

In case something is deprecated in Quilted Fabric API while not in Fabric API, it is very likely that an alternative in Quilt Standard Libraries exists and should be used instead.