Kiln Theme for IntelliJ

A warm dark and light theme for JetBrains IDEs. It uses charcoal and cream surfaces, a clay orange accent, and calm, earthy syntax colors. Each variant recolors the whole IDE, the editor, and the terminal.

Why "Kiln"

A kiln is where clay gets fired. The theme's accent is a warm clay orange, set against charcoal and cream. The palette was inspired by one of my favorite tools. I loved its warm, calm look and wanted that same feel in my IDE every day.

Install

You need IntelliJ IDEA 2026.2 or newer.

1. Download kiln-theme-<version>.zip from the latest release. Do not unzip it.
2. In IntelliJ, open Settings | Plugins, click the gear icon, and choose Install Plugin from Disk. Pick the zip.
3. Open Settings | Appearance & Behavior | Appearance and set Theme to Kiln Dark or Kiln Light.

The editor color scheme switches with the theme. If your code keeps its old colors, set Settings | Editor | Color Scheme to the matching Kiln scheme.

Kiln is tested with IntelliJ IDEA 2026.2.3. Other JetBrains IDEs on 2026.2 or newer share the same theme system, but they are not tested yet.

Feedback

Kiln is new, and feedback helps a lot. If something looks off, is hard to read, or still shows the default colors, open an issue with a screenshot.

Build from source

You need a JDK 17 or newer.

./gradlew buildPlugin

This writes build/distributions/kiln-theme-0.1.1.zip. The first build downloads IntelliJ IDEA 2026.2.3 to build against, which takes a few minutes. To use an IDE you already have, pass its install folder:

./gradlew buildPlugin -PlocalIdePath="/Applications/IntelliJ IDEA.app"

On Windows and Linux, pass the folder that contains the IDE's bin and lib folders.

Try it in a sandbox IDE

./gradlew runIde

This starts a separate IDE with the plugin installed and opens samples/src/dev/danvega/todos/TodoService.java. The sample has keywords, strings, annotations, fields, constants, Javadoc, a TODO, a warning, and an error, so most syntax colors are on screen at once. Pick a Kiln theme in the sandbox's settings the first time.

Change the colors

The palettes live in scripts/generate_themes.py. Edit the DARK or LIGHT dictionary, then regenerate the theme files. You need Python 3.

./gradlew generateThemes

This rewrites the four files in src/main/resources/themes and prints the contrast ratio of each syntax color against the editor background. Commit the regenerated files with your palette change. The build checks that they match the palettes.

Release a new version

1. Set pluginVersion in gradle.properties.
2. Commit, then tag the commit with the same version and push the tag:

git tag v0.1.0
git push origin v0.1.0

The Build workflow builds the plugin, then creates a GitHub release with the zip attached. It stops if the tag and pluginVersion do not match.

Good to know

• Kiln inherits from JetBrains' Islands themes (Islands Dark and Islands Light). Islands switched to its current color tokens in 2026.2, so older versions are not supported.
• Islands resolves its own named colors before a child theme's colors apply. Overriding one token does not reach the keys that point at it through another name. So the generator reads every Islands token from the IDE, resolves it through the Kiln palette, and writes all of them out as hex values. Do not hand-edit the generated files.
• The editor schemes use Darcula and Default as their parents. Those parents set some Java and Kotlin keys directly, so the schemes set those keys too, not only the DEFAULT_* ones.