# Kotlin

> Kotlin development: coroutines, Flow, Channels, testing with JUnit 5 and Kotest.

- Skill: `notque/kotlin` (Agent Skill, multi-file: 7 files)
- Install (CLI): `npx skillmds@latest add notque/kotlin`
- Raw SKILL.md: https://api.skillmd.com/api/skills/notque/kotlin/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: notque (https://skillmd.com/u/notque)
- Updated: 2026-09-10
- Page: https://skillmd.com/skills/notque/kotlin

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# Kotlin Skill

Kotlin coroutine patterns and testing: structured concurrency, Flow, StateFlow/SharedFlow, Channels, dispatchers, JUnit 5, Kotest, MockK, and coroutine test dispatchers.

## Reference Loading Table

| Signal | Reference | Size |
|--------|-----------|------|
| concurrency, scopes, cancellation, dispatchers, exception handling | `references/concurrency-patterns.md` | ~130 lines |
| Flow, StateFlow, SharedFlow, operators, flow builders | `references/flow-patterns.md` | ~120 lines |
| Channels, producer-consumer, fan-in, fan-out | `references/channel-patterns.md` | ~100 lines |
| GlobalScope, unstructured launch, CancellationException, failure modes | `references/preferred-patterns.md` | ~80 lines |
| coroutine skill overview, structured concurrency principles | `references/kotlin-coroutines.md` | ~55 lines |
| JUnit 5, Kotest, MockK, runTest, parameterized tests, assertions | `references/kotlin-testing.md` | ~290 lines |

**Loading rule.** Read the references whose signals match the task before responding.