A native Compose Multiplatform code editor — no WebView, no JS bridges. Built as a ground-up Kotlin port of CodeMirror 6, the industry-standard web editor.

Live Demo · Documentation · API Reference

Compose Multiplatform doesn't ship a code editor. Your options are embedding a WebView (heavy, hard to integrate) or building from scratch. KodeMirror gives you a real Compose component with the full feature set of CodeMirror 6:

• Syntax highlighting for 20+ languages, plus 100+ via legacy modes
• Vim mode with 600+ ported upstream tests
• Search/replace, autocompletion, linting, code folding
• Collaborative editing and side-by-side diff/merge
• Themes — 17 built-in themes (One Dark, Dracula, Solarized Light, Tomorrow, …) plus Material Design integration
• Real keyboard input pipeline — layout-aware key handling, no platform hacks

All from shared Kotlin code across every Compose target.

Try the live demo to see it in action — syntax highlighting, vim mode, autocompletion, and more, all running in the browser.

// build.gradle.kts
kotlin {
    sourceSets {
        commonMain.dependencies {
            implementation(platform("com.monkopedia.kodemirror:kodemirror-bom:0.3.6"))
            implementation("com.monkopedia.kodemirror:view")
            implementation("com.monkopedia.kodemirror:commands")
            implementation("com.monkopedia.kodemirror:basic-setup")
            // Pick your language(s)
            implementation("com.monkopedia.kodemirror:lang-javascript")
        }
    }
}

@Composable
fun Editor() {
    val session = rememberEditorSession(
        doc = "function hello() {\n    return 'world';\n}",
        extensions = basicSetup + javascript().extension
    )
    KodeMirror(session = session, modifier = Modifier.fillMaxSize())
}

Also add com.monkopedia.kodemirror:vim, :theme-one-dark, and :lang-python:

@Composable
fun VimEditor() {
    val session = rememberEditorSession(
        doc = "print(\"Hello, KodeMirror!\")",
        extensions = basicSetup + python().extension + vim() + oneDark
    )
    KodeMirror(session = session, modifier = Modifier.fillMaxSize())
}

JavaScript, TypeScript, HTML, CSS, Python, Java, Go, Rust, Markdown, JSON, YAML, XML, SQL, C++, PHP, and more — 20+ dedicated modules plus 100+ (including Kotlin) via legacy-modes.

One Dark, Dracula, Solarized Light, Tomorrow, Cobalt, Espresso, and 11 more, plus Material Design integration.

This is v0.3.6 — the API may evolve. Known issues to be aware of:

• Mobile/native — Android and iOS targets compile and pass unit tests but are not battle-tested on real devices yet

See all open issues for the full list.

Contributions are welcome! Please open an issue to discuss before submitting large changes.

Changelog entries go in changelog.d/, not in CHANGELOG.md. When your change is one a user reads about — behaviour, public API, the build, or user-facing docs — add a new file named <issue>.<section>.md — for example changelog.d/281.fixed.md — containing the markdown bullet(s) your change should appear as. A change with no user-visible effect needs none. CHANGELOG.md is assembled from those files at release time and has no [Unreleased] section to edit; editing it directly is refused by CI. One file per change means two pull requests never touch the same file, so they never conflict on the changelog. See changelog.d/README.md for the sections, the format and when an entry is expected, and run python3 .github/scripts/changelog.py check to validate.

Copyright 2026 Jason Monk

Licensed under the Apache License, Version 2.0

Originally based on CodeMirror 6 by Marijn Haverbeke, licensed under MIT. See NOTICE for details.