Version support and stability

Every Kore artifact carries two versions in one string: the Kore version, then the Minecraft version it targets.

dependencies {
	implementation("io.github.ayfri.kore:kore:2.15.0-26.2") // Kore 2.15.0, for Minecraft 26.2
}

The Version Matrix lists the latest Kore release for each Minecraft version, built from the GitHub releases on every website build.

Reading a version

Kore versions never contain a dash, so everything before the first - is the Kore version and everything after it is the Minecraft version:

That is why the string isn't plain semver: tools comparing versions have to split it first. The Kore part follows its own numbering:

All modules (kore, oop, helpers, bindings) and the Gradle plugin share the same version, so one string goes in both the plugins { } and the dependencies { } block.

One Minecraft version per release

A Kore release targets exactly one Minecraft version. That version decides:

• the generated registries (Items, Blocks, Biomes...), downloaded from the game data of that version, so an item removed from the game disappears from Items too;
• the shape of every command and JSON resource Kore writes;
• the default min_format/max_format of pack.mcmeta, both set to that version's pack format.

MINECRAFT_VERSION (io.github.ayfri.kore.generated) holds the targeted version at runtime.

Loading the pack in another Minecraft version only works when nothing it uses changed between the two versions. You can widen the declared range with minFormat/maxFormat and split version-specific files with overlays, both shown in Creating a Datapack, but Kore only checks its output against the targeted version.

Fixes land on the latest release only, they aren't backported to older Minecraft targets. To stay on an older game version, pin the last Kore release made for it in the Version Matrix.

Snapshot and pre-release builds

Kore publishes builds for Minecraft snapshots, pre-releases and release candidates, tagged with the game version (2.12.0-26.2-snapshot-8). They let you start on the next version early, with two caveats:

• Mojang changes snapshot features between snapshots, and Kore follows: an API added for one snapshot can change in the next one.
• They are GitHub pre-releases, so the stable rows of the Version Matrix skip them; the latest one shows up as the Snapshot row.

The -SNAPSHOT build is something else: a Maven snapshot published from every commit on master, see Getting Started. Use it to try a fix before its release, never in a pack you ship.

What counts as a breaking change

These bump the second number:

• removing or renaming a public declaration;
• changing a signature so existing calls stop compiling;
• changing what an existing call writes to the pack, when the game didn't ask for it.

A Minecraft update is the exception. When Mojang renames a command argument, removes a field or changes a JSON shape, Kore writes what the new version reads, even if that breaks a Kore API: a pack that compiles but fails to load is worse than a compile error. Those changes come with the Minecraft part of the version and are listed in the release notes.

Deprecations

A replaced API stays available under @Deprecated, with a message naming its replacement and, when the new call maps one to one, a ReplaceWith that the IDE applies through its Replace with quick fix:

advancement("get_diamond") {
	// Deprecated, the IDE offers the replacement
	criteria("get_diamond", InventoryChanged())

	// Current form
	criteria {
		inventoryChanged("get_diamond")
	}
}

Fields the game ignores are deprecated with the reason and the field it reads instead, like TrimMaterial.overrideArmorMaterials, which points to overrideArmorAssets.

Release notes

Every release lists its additions, fixes and breaking changes on the Updates page and on GitHub releases. Read the notes before bumping the second number or the Minecraft part.

What to read next

• Getting Started - adding Kore to a project, stable or snapshot
• Creating a Datapack - pack format ranges and overlays
• Debugging - finding what broke after an update