Free Rainbow Brackets (Delimiters) Simplest delimiter coloring free! Rainbow coloring for (), [], {} based on nesting level. Works in RustRover, Rider, and other IntelliJ-based IDEs.

A lightweight alternative to paid “rainbow brackets” plugins: it colors matching brackets by nesting depth so you can read deeply nested code faster.

Screenshot

Features

• Rainbow coloring for (), [], {} by nesting level
• Skips strings and comments when possible (lexer-based; falls back to a manual parser where needed)
• Lightweight: highlights only the visible area (plus a small margin)
• No settings required — works out of the box

Supported IDEs

This is a plain IntelliJ Platform plugin (editor-level highlighting), so it can work in many JetBrains IDEs:

• RustRover
• Rider
• IntelliJ IDEA / CLion / WebStorm / etc.

Compatibility is controlled by the build number range injected into plugin.xml during build (sinceBuild / untilBuild in patchPluginXml).

Supported file types

The plugin is enabled for common code extensions (you can change the list in code):

• Rust: .rs
• C#: .cs
• JVM: .java, .kt, .kts
• C/C++: .c, .h, .cc, .cpp, .cxx, .hpp, .hxx
• JS/TS: .js, .ts, .jsx, .tsx
• Other: .py, .go, .swift, lua, json, hlsl, shader, php

To customize: edit ENABLED_EXT in src/main/kotlin/dev/yaro/rainbowbraces/RainbowBracesEditorListener.kt.

Installation

From JetBrains Marketplace

If/when the plugin is published, install it from Settings → Plugins → Marketplace and search for Free Rainbow Braces.

From ZIP (local install)

1. Build the plugin ZIP (see “Build” below).
2. In your IDE: Settings → Plugins → ⚙ → Install Plugin from Disk…
3. Select the generated ZIP and restart the IDE.

Development

Run in a sandbox IDE

runIde starts a separate IDE instance (sandbox) with your plugin already loaded.

• From IntelliJ: run the Gradle task runIde
• Or from terminal:

./gradlew runIde

Then open any supported file (e.g., test.rs, test.cs) and type nested code to see the coloring.

Build a distributable ZIP

./gradlew buildPlugin -x buildSearchableOptions

Output ZIP:

build/distributions/*.zip

Note

• Rider C# editor is special (ReSharper backend). Some Rider builds expose fewer lexer/PSI features in the frontend editor. The plugin has a manual fallback, but behavior can still vary across Rider versions.
• If you see “not compatible with IDE build …” during install, adjust the build range in patchPluginXml (sinceBuild / untilBuild) and rebuild the ZIP.

Open Source

MIT