Gradle Build Performance
Communityrcosteira79
Use when Android/Gradle builds are slow — diagnosing bottlenecks with build scans, enabling configuration cache, migrating kapt to KSP, fixing cache misses, and optimizing CI/CD build times.
Overview
- Repository
- rcosteira79/android-skills
- Publisher
- rcosteira79
- Stars
- 174
- Forks
- 21
- Bundled files
- 0
- License
- MIT
- Updated
- Nov 10, 2026
Installation
tmp=$(mktemp -d)
git clone --depth 1 https://github.com/rcosteira79/android-skills.git "$tmp"
mkdir -p ~/.claude/skills
cp -R "$tmp/plugins/android-skills/skills/gradle-build-performance" ~/.claude/skills/gradle-build-performance
rm -rf "$tmp"tmp=$(mktemp -d)
git clone --depth 1 https://github.com/rcosteira79/android-skills.git "$tmp"
mkdir -p ~/.codex/skills
cp -R "$tmp/plugins/android-skills/skills/gradle-build-performance" ~/.codex/skills/gradle-build-performance
rm -rf "$tmp"Install the Gradle Build Performance agent skill from https://github.com/rcosteira79/android-skills/tree/main/plugins/android-skills/skills/gradle-build-performance into this project's skills folder.Instructions
Gradle Build Performance
This reference covers the workflow discipline plus the patterns that move the needle and are easy to get wrong, not the standard knobs (org.gradle.caching, org.gradle.parallel, org.gradle.jvmargs, android.nonTransitiveRClass, kapt → ksp).
Workflow: measure a baseline (clean + incremental) → ./gradlew assembleDebug --scan (or --profile for a no-upload report) → find the slow phase (configuration / execution / dependency resolution) in the Build Scan timeline → apply one optimization at a time → measure again. Batching changes means you never learn what helped.
Configuration phase — the cheapest wins
- Configuration cache (
org.gradle.configuration-cache=true, AGP 8+) skips the entire configuration phase when inputs are unchanged. Start withorg.gradle.configuration-cache.problems=warn, move tofailonce clean. - No I/O during configuration. A
file("version.txt").readText(), a network call, orexec {}at configuration time breaks the configuration cache and slows every build — defer it to execution:providers.fileContents(layout.projectDirectory.file("version.txt")).asText. - Lazy task registration —
tasks.register("x") { … }(configured only if it's in the execution graph), nevertasks.create("x") { … }(eager). - Convention plugins, not
subprojects {}/allprojects {}— those root-build blocks eagerly evaluate every subproject. Move shared config into convention plugins (seeandroid-skills:android-gradle-logic).
kapt → KSP (mandatory on AGP 9)
KSP is ~2× faster than kapt, and AGP 9 makes the migration mandatory — it has built-in Kotlin support and org.jetbrains.kotlin.kapt is incompatible with it. Migrate to KSP (AGP 9 needs KSP 2.3.6+ and Hilt 2.59.2+; Room and Moshi support KSP too), or fall back to com.android.legacy-kapt (same version as AGP) for annotation processors with no KSP equivalent. The step-by-step migration is in Google's agp-9-upgrade skill; see JetBrains' kotlin-tooling-agp9-migration skill for the broader AGP 9 mechanics.
Dependency resolution
- Pin versions — a dynamic
1.0.+or-SNAPSHOTforces a network resolution check on every build. Pin1.2.3. - Repository order — Gradle checks repositories in declaration order; put the most-used first (
google()thenmavenCentral(), third-party last).
A reasonable gradle.properties baseline
org.gradle.configuration-cache=true
org.gradle.caching=true
org.gradle.parallel=true
org.gradle.jvmargs=-Xmx4g -XX:+UseParallelGC
android.nonTransitiveRClass=trueFAQ
What does Gradle Build Performance do?
Use when Android/Gradle builds are slow — diagnosing bottlenecks with build scans, enabling configuration cache, migrating kapt to KSP, fixing cache misses, and optimizing CI/CD build times.
Who made Gradle Build Performance?
rcosteira79 (a community member) publishes it in the rcosteira79/android-skills repository on GitHub.
Is Gradle Build Performance free?
Yes. Gradle Build Performance is open source, published by rcosteira79 under the MIT license.
What comes with Gradle Build Performance?
Just its instructions. Everything the agent needs is in one SKILL.md file.
Which agents can use Gradle Build Performance?
Any coding agent that reads SKILL.md files, including Claude Code, Codex, Cursor, GitHub Copilot and Gemini CLI. The agent loads the skill when a task matches its description.
What are agent skills?
An agent skill is a folder with a SKILL.md file: instructions that teach a coding agent how to do one kind of task, and optionally files it can read while it works. The agent keeps only the skill's name and description in mind and reads the rest when a task calls for it.
How are agent skills different from MCP servers?
An MCP server gives an agent new tools to call, code that runs somewhere and returns results. A skill gives it knowledge: how to approach a task with the tools it already has. Many agents use both.
How can my agent test my Android app?
Robomori lets coding agents create, start and control Android emulators and devices from one command, so they can install your app, take screenshots and check dark mode, font sizes and languages.
Records and analyzes Android performance data and diagnoses performance bottlenecks across user apps, system apps, and system services, even if the user does not explicitly mention profiling or traces. Use when: recording system traces, CPU call stacks, Vulkan GPU/DRM memory, or Java/native heap profiles; analyzing Perfetto traces for UI jank, frame drops, ANRs, or app startup latency issues; investigating CPU bottlenecks, IPC/Binder storms, or thread scheduling stalls; diagnosing battery drain, modem power rails, and kernel wake locks; debugging memory pressure, Low Memory Kills (LMK), OOMs, leaks, and allocation churn; performing A/B baseline trace comparisons to find regressions; executing ad hoc PerfettoSQL queries on Android traces.
Audits Android codebases for ANR risks and diagnoses ANR stack dumps. Use this skill when scanning Android code for ANR risks or triaging ANR stack dumps. Don't use for non-ANR crashes, dropped frames, general CPU profiling, or Perfetto system traces.
Diagnose and optimize Android Jetpack Compose UI code. Use this skill when analyzing performance bottlenecks of existing code to minimize recomposition overhead and prevent dropped frames and UI lag.
Analyzes Android build files and R8 keep rules to identify redundancies, broad package-wide rules, and rules that subsume library consumer keep rules. Use this skill when developers want to optimize their Android app's size, remove redundant or overly broad keep rules, or troubleshoot ProGuard configurations. Don't use for general Gradle build errors, Compose UI performance, or runtime CPU profiling.
