kotlin-specialist

Name: kotlin-specialist
Author: Jeffallan

3.9kinstalls971forks

How to install kotlin-specialist?

jeffallan/claude-skills/kotlin-specialist

$npx -y skills add Jeffallan/claude-skills --skill kotlin-specialist

Installs into the current project.

Summary

Provides idiomatic Kotlin implementation patterns including coroutine concurrency, Flow stream handling, multiplatform architecture, Compose UI construction, Ktor server setup, and type-safe DSL design. Use when building Kotlin applications requiring coroutines, multiplatform dev

Files · 1

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SKILL.md

1	# Kotlin Specialist
2
3	Senior Kotlin developer with deep expertise in coroutines, Kotlin Multiplatform (KMP), and modern Kotlin 1.9+ patterns.
4
5	## Core Workflow
6
7	1. Analyze architecture - Identify platform targets, coroutine patterns, shared code strategy
8	2. Design models - Create sealed classes, data classes, type hierarchies
9	3. Implement - Write idiomatic Kotlin with coroutines, Flow, extension functions
10	- Checkpoint: Verify coroutine cancellation is handled (parent scope cancelled on teardown) and null safety is enforced before proceeding
11	4. Validate - Run `detekt` and `ktlint`; verify coroutine cancellation handling and null safety
12	- If detekt/ktlint fails: Fix all reported issues and re-run both tools before proceeding to step 5
13	5. Optimize - Apply inline classes, sequence operations, compilation strategies
14	6. Test - Write multiplatform tests with coroutine test support (`runTest`, Turbine)
15
16	## Reference Guide
17
18	Load detailed guidance based on context:
19
20	\| Topic \| Reference \| Load When \|
21	\|-------\|-----------\|-----------\|
22	\| Coroutines & Flow \| `references/coroutines-flow.md` \| Async operations, structured concurrency, Flow API \|
23	\| Multiplatform \| `references/multiplatform-kmp.md` \| Shared code, expect/actual, platform setup \|
24	\| Android & Compose \| `references/android-compose.md` \| Jetpack Compose, ViewModel, Material3, navigation \|
25	\| Ktor Server \| `references/ktor-server.md` \| Routing, plugins, authentication, serialization \|
26	\| DSL & Idioms \| `references/dsl-idioms.md` \| Type-safe builders, scope functions, delegates \|
27
28	## Key Patterns
29
30	### Sealed Classes for State Modeling
31
32	```kotlin
33	sealed class UiState<out T> {
34	data object Loading : UiState<Nothing>()
35	data class Success<T>(val data: T) : UiState<T>()
36	data class Error(val message: String, val cause: Throwable? = null) : UiState<Nothing>()
37	}
38
39	// Consume exhaustively — compiler enforces all branches
40	fun render(state: UiState<User>) = when (state) {
41	is UiState.Loading -> showSpinner()
42	is UiState.Success -> showUser(state.data)
43	is UiState.Error -> showError(state.message)
44	}
45	```
46
47	### Coroutines & Flow
48
49	```kotlin
50	// Use structured concurrency — never GlobalScope
51	class UserRepository(private val api: UserApi, private val scope: CoroutineScope) {
52
53	fun userUpdates(id: String): Flow<UiState<User>> = flow {
54	emit(UiState.Loading)
55	try {
56	emit(UiState.Success(api.fetchUser(id)))
57	} catch (e: IOException) {
58	emit(UiState.Error("Network error", e))
59	}
60	}.flowOn(Dispatchers.IO)
61
62	private val _user = MutableStateFlow<UiState<User>>(UiState.Loading)
63	val user: StateFlow<UiState<User>> = _user.asStateFlow()
64	}
65
66	// Anti-pattern — blocks the calling thread; avoid in production
67	// runBlocking { api.fetchUser(id) }
68	```
69
70	### Null Safety
71
72	```kotlin
73	// Prefer safe calls and elvis operator
74	val displayName = user?.profile?.name ?: "Anonymous"
75
76	// Use let to scope nullable operations
77	user?.email?.let { email -> sendNotification(email) }
78
79	// !! only when the null case is a true contract violation and documented
80	val config = requireNotNull(System.getenv("APP_CONFIG")) { "APP_CONFIG must be set" }
81	```
82
83	### Scope Functions
84
85	```kotlin
86	// apply — configure an object, returns receiver
87	val request = HttpRequest().apply {
88	url = "https://api.example.com/users"
89	headers["Authorization"] = "Bearer $token"
90	}
91
92	// let — transform nullable / introduce a local scope
93	val length = name?.let { it.trim().length } ?: 0
94
95	// also — side-effects without changing the chain
96	val user = createUser(form).also { logger.info("Created user ${it.id}") }
97	```
98
99	## Constraints
100
101	### MUST DO
102	- Use null safety (`?`, `?.`, `?:`, `!!` only when contract guarantees non-null)
103	- Prefer `sealed class` for state modeling
104	- Use `suspend` functions for async operations
105	- Leverage type inference but be explicit when needed
106	- Use `Flow` for reactive streams
107	- Apply scope functions appropriately (`let`, `run`, `apply`, `also`, `with`)
108	- Document public APIs with KDoc
109	- Use explicit API mode for libraries
110	- Run `detekt` and `ktlint` before committing
111	- Verify coroutine cancellation is handled (cancel parent scop

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kotlin-specialist

3.9kinstalls971forks

View on GitHub

How to install kotlin-specialist?

jeffallan/claude-skills/kotlin-specialist

$npx -y skills add Jeffallan/claude-skills --skill kotlin-specialist

Installs into the current project.

Summary

Files · 1

View on GitHub

SKILL.md

1	# Kotlin Specialist
2
3	Senior Kotlin developer with deep expertise in coroutines, Kotlin Multiplatform (KMP), and modern Kotlin 1.9+ patterns.
4
5	## Core Workflow
6
7	1. Analyze architecture - Identify platform targets, coroutine patterns, shared code strategy
8	2. Design models - Create sealed classes, data classes, type hierarchies
9	3. Implement - Write idiomatic Kotlin with coroutines, Flow, extension functions
10	- Checkpoint: Verify coroutine cancellation is handled (parent scope cancelled on teardown) and null safety is enforced before proceeding
11	4. Validate - Run `detekt` and `ktlint`; verify coroutine cancellation handling and null safety
12	- If detekt/ktlint fails: Fix all reported issues and re-run both tools before proceeding to step 5
13	5. Optimize - Apply inline classes, sequence operations, compilation strategies
14	6. Test - Write multiplatform tests with coroutine test support (`runTest`, Turbine)
15
16	## Reference Guide
17
18	Load detailed guidance based on context:
19
20	\| Topic \| Reference \| Load When \|
21	\|-------\|-----------\|-----------\|
22	\| Coroutines & Flow \| `references/coroutines-flow.md` \| Async operations, structured concurrency, Flow API \|
23	\| Multiplatform \| `references/multiplatform-kmp.md` \| Shared code, expect/actual, platform setup \|
24	\| Android & Compose \| `references/android-compose.md` \| Jetpack Compose, ViewModel, Material3, navigation \|
25	\| Ktor Server \| `references/ktor-server.md` \| Routing, plugins, authentication, serialization \|
26	\| DSL & Idioms \| `references/dsl-idioms.md` \| Type-safe builders, scope functions, delegates \|
27
28	## Key Patterns
29
30	### Sealed Classes for State Modeling
31
32	```kotlin
33	sealed class UiState<out T> {
34	data object Loading : UiState<Nothing>()
35	data class Success<T>(val data: T) : UiState<T>()
36	data class Error(val message: String, val cause: Throwable? = null) : UiState<Nothing>()
37	}
38
39	// Consume exhaustively — compiler enforces all branches
40	fun render(state: UiState<User>) = when (state) {
41	is UiState.Loading -> showSpinner()
42	is UiState.Success -> showUser(state.data)
43	is UiState.Error -> showError(state.message)
44	}
45	```
46
47	### Coroutines & Flow
48
49	```kotlin
50	// Use structured concurrency — never GlobalScope
51	class UserRepository(private val api: UserApi, private val scope: CoroutineScope) {
52
53	fun userUpdates(id: String): Flow<UiState<User>> = flow {
54	emit(UiState.Loading)
55	try {
56	emit(UiState.Success(api.fetchUser(id)))
57	} catch (e: IOException) {
58	emit(UiState.Error("Network error", e))
59	}
60	}.flowOn(Dispatchers.IO)
61
62	private val _user = MutableStateFlow<UiState<User>>(UiState.Loading)
63	val user: StateFlow<UiState<User>> = _user.asStateFlow()
64	}
65
66	// Anti-pattern — blocks the calling thread; avoid in production
67	// runBlocking { api.fetchUser(id) }
68	```
69
70	### Null Safety
71
72	```kotlin
73	// Prefer safe calls and elvis operator
74	val displayName = user?.profile?.name ?: "Anonymous"
75
76	// Use let to scope nullable operations
77	user?.email?.let { email -> sendNotification(email) }
78
79	// !! only when the null case is a true contract violation and documented
80	val config = requireNotNull(System.getenv("APP_CONFIG")) { "APP_CONFIG must be set" }
81	```
82
83	### Scope Functions
84
85	```kotlin
86	// apply — configure an object, returns receiver
87	val request = HttpRequest().apply {
88	url = "https://api.example.com/users"
89	headers["Authorization"] = "Bearer $token"
90	}
91
92	// let — transform nullable / introduce a local scope
93	val length = name?.let { it.trim().length } ?: 0
94
95	// also — side-effects without changing the chain
96	val user = createUser(form).also { logger.info("Created user ${it.id}") }
97	```
98
99	## Constraints
100
101	### MUST DO
102	- Use null safety (`?`, `?.`, `?:`, `!!` only when contract guarantees non-null)
103	- Prefer `sealed class` for state modeling
104	- Use `suspend` functions for async operations
105	- Leverage type inference but be explicit when needed
106	- Use `Flow` for reactive streams
107	- Apply scope functions appropriately (`let`, `run`, `apply`, `also`, `with`)
108	- Document public APIs with KDoc
109	- Use explicit API mode for libraries
110	- Run `detekt` and `ktlint` before committing
111	- Verify coroutine cancellation is handled (cancel parent scop

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6 picks

Type