CLAUDE.md
CLAUDE.md for Kotlin
CLAUDE.md is the project memory file Claude Code reads from the repository root. It is the right place for stack rules you do not want to repeat in every chat. This copy is written for a Kotlin project. This repository is an Android app in Kotlin. Match Compose or Views, whichever the module uses. Keep disk and network work off the main thread.
The example uses a balanced, readable style, pragmatic tests, and comments only where the intent is not obvious. Open the generator to make the agent stricter, switch to test-first, quiet the comments, or pick a different file.
The example assumes Kotlin on Android. It does not assume Compose, Hilt, or a particular navigation library unless the Gradle module already depends on them.
Example file
Balanced strictness, readable style, pragmatic tests. Download name: CLAUDE.md
# CLAUDE.md
Project memory for Claude Code in this Kotlin repository. Read it before editing. Other agents can follow the same rules.
## Stack
This repository is an Android app in Kotlin. Match Compose or Views, whichever the module uses. Keep disk and network work off the main thread.
## Layout
- UI lives in the feature module that already owns the screen.
- ViewModels expose state. They do not hold a Context that can leak an Activity.
- Data sources sit behind the repository or data layer the app already has.
## Commands
- Unit tests: `./gradlew test`
- Lint: `./gradlew lint`
- Assemble: `./gradlew assembleDebug`
Use the script the repo already defines when it differs from the command above.
## Conventions
- Use coroutines with a scope that is cancelled. Do not use GlobalScope.
- Collect flows in lifecycle-aware scopes.
- Keep Compose functions pure. Side effects go in LaunchedEffect or a ViewModel.
- If the screen is XML, do not rewrite it into Compose unless the task is that migration.
- Prefer the project's dependency-injection style. Do not add a second one.
- String resources go in `strings.xml` when the screen is localized.
## Testing
Add or update tests when behavior changes.
Add a JVM unit test for the ViewModel or use case. Use instrumented tests only when you need the framework.
## Style
- Optimize for the next reader over the shortest diff.
- Comment only when the why is non-obvious.
- Name things the way neighboring files already do.
- Do not reformat code you did not change.
## Errors
- Fail at the boundary. Do not swallow errors.
- Expose an error state the UI can render. Do not swallow a cancellation or a failed network call.
## Scope
- Do the requested task. Do not refactor unrelated code.
- Match the rigor already in the repo. Fix what you touch.
- Ask one clarifying question only when the task cannot be finished without it. Otherwise state the assumption and continue.
## Avoid
- Do not touch views from a background dispatcher.
- Do not store a Context in a singleton.
- Do not ignore a failing Gradle warning you introduced.
- Do not hard-code an API host that the build flavors already provide.
## Done when
- The requested behavior works.
- `./gradlew test` passes for the module you changed.
- The diff stays inside the task.
- You list anything you could not run.
Add it to the project
01
Copy a starting file
Copy the example CLAUDE.md on this page, or open the generator if you want different testing, strictness, or comment rules.
02
Save it at CLAUDE.md
Save it as `CLAUDE.md` at the root of the Kotlin repo. Claude Code loads it when a session starts. A nested CLAUDE.md applies to that directory.
03
Start a fresh agent session
Rules files are read when a session starts. A chat that is already open may still be using the old instructions.
04
Give it one small task
Ask for one change a Kotlin agent often gets wrong, such as a ViewModel that exposes state and does not hold an Activity reference. If it ignores the file, confirm the path and start a new session.
Questions about this file
Where do I put CLAUDE.md in a Kotlin repo?
Save it as `CLAUDE.md` at the root of the Kotlin repo. Claude Code loads it when a session starts. A nested CLAUDE.md applies to that directory.
Which tools read this CLAUDE.md?
Claude Code reads CLAUDE.md as project memory. Other agents can follow the same markdown if you point them at it, but Claude Code is the tool that loads it automatically.
What does the Kotlin example assume?
The example assumes Kotlin on Android. It does not assume Compose, Hilt, or a particular navigation library unless the Gradle module already depends on them.
Does VibeSpell upload my repository?
No. Recipe pages are static, and the generator builds the file in your browser from the options you pick. Your source code never leaves the machine.
Other files for Kotlin
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AGENTS.md
system prompt
system-prompt.md
Copilot instructions
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Windsurf rules
.windsurf/rules/project.md
Cline rules
.clinerules
GEMINI.md
GEMINI.md
Cursor testing rule
.cursor/rules/testing.mdc
Cursor security rule
.cursor/rules/security.mdc
CLAUDE.md for other stacks
- CLAUDE.md for Next.js
- CLAUDE.md for React
- CLAUDE.md for Vue
- CLAUDE.md for SvelteKit
- CLAUDE.md for Node.js
- CLAUDE.md for FastAPI
- CLAUDE.md for Django
- CLAUDE.md for Go
- CLAUDE.md for Rust
- CLAUDE.md for Unity
- CLAUDE.md for Godot
- CLAUDE.md for Laravel
- CLAUDE.md for Rails
- CLAUDE.md for Flutter
- CLAUDE.md for Swift
- CLAUDE.md for Unreal
- CLAUDE.md for Next.js + Supabase
- CLAUDE.md for T3
- CLAUDE.md for Astro
- CLAUDE.md for Remix
- CLAUDE.md for Nuxt
- CLAUDE.md for Electron
- CLAUDE.md for Tauri
- CLAUDE.md for Expo
- CLAUDE.md for Spring Boot
- CLAUDE.md for .NET
- CLAUDE.md for Phaser
- CLAUDE.md for Bevy
- CLAUDE.md for Roblox
- CLAUDE.md for Python ML
- CLAUDE.md for LangChain