6.0.0-beta01

[jordond]

6.0 is a big release. The color engine is now generated from Google's upstream Kotlin source, the
library is split into one module per UI toolkit, and there are new adapters for Compose Unstyled,
Compose Fluent and kmpalette.

Important

6.0 has breaking changes, and some colors change even when your code compiles without changes.
Read the migration guide before upgrading.

New engine

material-color-utilities is no longer a hand-written port. It is generated from upstream's
Kotlin source at a pinned revision, and its output is tested against upstream's Java and Kotlin to
match ARGB for ARGB.

This also brings:

• The 2026 color spec and the new CMF variant, available as PaletteStyle.Cmf(tertiarySeedColor)
• SPEC_2025 as the default spec. Pass SPEC_2021 to keep the 5.x colors.
• Nullable results where upstream has them, for example Contrast.lighter returns null instead
  of -1.0

Modules

material-kolor is now several artifacts. Depend on the one for your toolkit:

Artifact	For
material-kolor-material3	Material 3 apps
material-kolor-core	Your own theme, with no Material 3 dependency
material-kolor-unstyled	New. Compose Unstyled theming
material-kolor-fluent	New. Compose Fluent accent shades generated from a seed
material-kolor-palette	New. Seed colors from images with kmpalette
material-color-utilities	The engine on its own

Other changes

• rememberTonalPalette, TonalPalette.toneColor and TonalPalette.onTone for building your own
  themes from tonal palettes
• PaletteStyle is now a sealed interface. It is @Serializable and has parse, fromName and
  KnownStyles.
• A primary override in the theme state now sets only the primary palette. The seed still drives
  the rest.
• Image helpers sample the image down to 128x128 before quantizing, so large images are much
  faster
• Fixed release AAB builds failing on AGP 9.4+ with "Entry name contains invalid characters"
  (Colon in module name (MaterialKolor:material-kolor) causes release AAB build failure on AGP 9.4.0+ ( Entry name contains invalid characters) #542)
• Removed the *Kt consumer keep rules. Consumers don't need to do anything.

Deprecated

These will be removed in 7.0:

• The overloads that take primary in
• The ImageBitmap helpers in core. Use material-kolor-palette instead.

Builder

materialkolor.com was rewritten from scratch. It previews themes in
Material 3, Compose Unstyled, Compose Frts the code for each.

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This discussion was created from the release 6.0.0-beta01.