android-gradle-logic

Name: android-gradle-logic
Author: rcosteira79

47installs13forks

How to install android-gradle-logic?

rcosteira79/android-skills/android-gradle-logic

$npx -y skills add rcosteira79/android-skills --skill android-gradle-logic

Installs into the current project.

Summary

Use when setting up or refactoring Android Gradle build logic — convention plugins, composite builds, version catalogs, and shared build configuration across modules.

Files · 1

View on GitHub

SKILL.md

1	# Android Gradle Build Logic
2
3	Centralise build configuration in reusable Convention Plugins inside a `build-logic/` composite build, so each module's `build.gradle.kts` collapses to `plugins { alias(libs.plugins.myapp.android.library) }` plus a `namespace`.
4
5	The canonical worked example is [nowinandroid's `build-logic/`](https://github.com/android/nowinandroid/tree/main/build-logic) — start from it rather than hand-rolling. This skill covers the three wiring details that are easy to get wrong, plus the AGP 9 deltas.
6
7	## The wiring gotchas
8
9	1. `build-logic` does NOT inherit the root version catalog — recreate it. A composite build has its own `settings.gradle.kts`; the root `libs` catalog is invisible inside `build-logic` until you declare it. Without this the convention plugins can't reference `libs.*` and won't compile:
10
11	```kotlin
12	// build-logic/settings.gradle.kts
13	dependencyResolutionManagement {
14	versionCatalogs {
15	create("libs") { from(files("../gradle/libs.versions.toml")) }
16	}
17	}
18	```
19
20	2. Declare the convention-plugin ids in `[plugins]` with `version = "unspecified"` — otherwise `alias(libs.plugins.myapp.android.library)` in a module file doesn't resolve (Gradle treats it as a versioned external plugin and fails to find it). The `id` here must match the one you `register(...)`:
21
22	```toml
23	# gradle/libs.versions.toml
24	[plugins]
25	myapp-android-application = { id = "myapp.android.application", version = "unspecified" }
26	myapp-android-library = { id = "myapp.android.library", version = "unspecified" }
27	myapp-android-compose = { id = "myapp.android.compose", version = "unspecified" }
28	```
29
30	3. Set the JVM toolchain via Kotlin's extension, not `JavaPluginExtension`. AGP's `com.android.application` / `com.android.library` plugins do not apply Gradle's `java` plugin, so `configure<JavaPluginExtension> { ... }` throws "Extension of type JavaPluginExtension does not exist" and fails configuration in every module. Use the Kotlin extension inside the convention plugin:
31
32	```kotlin
33	extensions.configure<org.jetbrains.kotlin.gradle.dsl.KotlinAndroidProjectExtension> {
34	jvmToolchain(21)
35	}
36	// equivalently: kotlin { jvmToolchain(21) }
37	```
38
39	## AGP 9 Implications
40
41	The convention plugin pattern above targets AGP 8. AGP 9 changes several things that hit build logic directly: it drops the standalone `org.jetbrains.kotlin.android` plugin (Kotlin is built into `com.android.application` / `com.android.library`), removes `BaseExtension` and the old variant APIs (`applicationVariants` → `androidComponents { onVariants { … } }`), moves `kotlinOptions {}` to a top-level `kotlin { compilerOptions { … } }`, and makes `kapt` incompatible (migrate to KSP). Any convention plugin that touches these needs updating.
42
43	Defer to the dedicated migration skills for the mechanics rather than duplicating the steps here: Google's [`agp-9-upgrade`](https://github.com/android/skills/tree/main/agp-9-upgrade) for pure-Android projects, JetBrains' [`kotlin-tooling-agp9-migration`](https://github.com/Kotlin/kotlin-agent-skills/tree/main/skills/kotlin-tooling-agp9-migration) for KMP, and this repo's `gradle-build-performance` skill for the kapt → KSP step.
44
45	## Checklist
46
47	- [ ] `build-logic` included as a composite build (`includeBuild("build-logic")`) in the root `settings.gradle.kts`
48	- [ ] `build-logic/settings.gradle.kts` recreates the `libs` catalog via `from(files("../gradle/libs.versions.toml"))`
49	- [ ] Convention plugins `register`-ed with stable ids and declared in `[plugins]` with `version = "unspecified"`
50	- [ ] JVM toolchain set via `KotlinAndroidProjectExtension` / `kotlin { jvmToolchain() }`, never `JavaPluginExtension`
51	- [ ] `compileSdk` / `minSdk` / Compose set once in the plugins, not per module

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Type

android-gradle-logic

47installs13forks

View on GitHub

How to install android-gradle-logic?

rcosteira79/android-skills/android-gradle-logic

$npx -y skills add rcosteira79/android-skills --skill android-gradle-logic

Installs into the current project.

Summary

Use when setting up or refactoring Android Gradle build logic — convention plugins, composite builds, version catalogs, and shared build configuration across modules.

Files · 1

View on GitHub

SKILL.md

1	# Android Gradle Build Logic
2
3	Centralise build configuration in reusable Convention Plugins inside a `build-logic/` composite build, so each module's `build.gradle.kts` collapses to `plugins { alias(libs.plugins.myapp.android.library) }` plus a `namespace`.
4
5	The canonical worked example is [nowinandroid's `build-logic/`](https://github.com/android/nowinandroid/tree/main/build-logic) — start from it rather than hand-rolling. This skill covers the three wiring details that are easy to get wrong, plus the AGP 9 deltas.
6
7	## The wiring gotchas
8
9	1. `build-logic` does NOT inherit the root version catalog — recreate it. A composite build has its own `settings.gradle.kts`; the root `libs` catalog is invisible inside `build-logic` until you declare it. Without this the convention plugins can't reference `libs.*` and won't compile:
10
11	```kotlin
12	// build-logic/settings.gradle.kts
13	dependencyResolutionManagement {
14	versionCatalogs {
15	create("libs") { from(files("../gradle/libs.versions.toml")) }
16	}
17	}
18	```
19
20	2. Declare the convention-plugin ids in `[plugins]` with `version = "unspecified"` — otherwise `alias(libs.plugins.myapp.android.library)` in a module file doesn't resolve (Gradle treats it as a versioned external plugin and fails to find it). The `id` here must match the one you `register(...)`:
21
22	```toml
23	# gradle/libs.versions.toml
24	[plugins]
25	myapp-android-application = { id = "myapp.android.application", version = "unspecified" }
26	myapp-android-library = { id = "myapp.android.library", version = "unspecified" }
27	myapp-android-compose = { id = "myapp.android.compose", version = "unspecified" }
28	```
29
30	3. Set the JVM toolchain via Kotlin's extension, not `JavaPluginExtension`. AGP's `com.android.application` / `com.android.library` plugins do not apply Gradle's `java` plugin, so `configure<JavaPluginExtension> { ... }` throws "Extension of type JavaPluginExtension does not exist" and fails configuration in every module. Use the Kotlin extension inside the convention plugin:
31
32	```kotlin
33	extensions.configure<org.jetbrains.kotlin.gradle.dsl.KotlinAndroidProjectExtension> {
34	jvmToolchain(21)
35	}
36	// equivalently: kotlin { jvmToolchain(21) }
37	```
38
39	## AGP 9 Implications
40
41	The convention plugin pattern above targets AGP 8. AGP 9 changes several things that hit build logic directly: it drops the standalone `org.jetbrains.kotlin.android` plugin (Kotlin is built into `com.android.application` / `com.android.library`), removes `BaseExtension` and the old variant APIs (`applicationVariants` → `androidComponents { onVariants { … } }`), moves `kotlinOptions {}` to a top-level `kotlin { compilerOptions { … } }`, and makes `kapt` incompatible (migrate to KSP). Any convention plugin that touches these needs updating.
42
43	Defer to the dedicated migration skills for the mechanics rather than duplicating the steps here: Google's [`agp-9-upgrade`](https://github.com/android/skills/tree/main/agp-9-upgrade) for pure-Android projects, JetBrains' [`kotlin-tooling-agp9-migration`](https://github.com/Kotlin/kotlin-agent-skills/tree/main/skills/kotlin-tooling-agp9-migration) for KMP, and this repo's `gradle-build-performance` skill for the kapt → KSP step.
44
45	## Checklist
46
47	- [ ] `build-logic` included as a composite build (`includeBuild("build-logic")`) in the root `settings.gradle.kts`
48	- [ ] `build-logic/settings.gradle.kts` recreates the `libs` catalog via `from(files("../gradle/libs.versions.toml"))`
49	- [ ] Convention plugins `register`-ed with stable ids and declared in `[plugins]` with `version = "unspecified"`
50	- [ ] JVM toolchain set via `KotlinAndroidProjectExtension` / `kotlin { jvmToolchain() }`, never `JavaPluginExtension`
51	- [ ] `compileSdk` / `minSdk` / Compose set once in the plugins, not per module

People who liked this also viewed

6 picks

Type