You want to improve the performance of your Gradle build. What optimizations can you apply?

Question

Accepted Answer

Gradle build performance tuning focuses on avoiding redundant work and maximizing parallelism so incremental builds and CI runs finish faster. Most gains come from a handful of well-known settings rather than rewriting build logic.

Key Points:
• Enable the Gradle Daemon (org.gradle.daemon=true) so the JVM stays warm between builds instead of restarting each time.
• Turn on the build cache (org.gradle.caching=true) to reuse task outputs from previous builds or other machines.
• Enable parallel execution (org.gradle.parallel=true) so independent modules build concurrently across CPU cores.
• Use configuration cache and configuration-on-demand to skip re-evaluating projects that aren't needed for the current task.
• Tune JVM memory/GC flags (org.gradle.jvmargs) since a small heap causes excessive garbage collection during large builds.
• Regularly audit and prune unused dependencies, since dependency resolution time grows with the dependency graph.

Example:
On a multi-module Android project, simply adding org.gradle.parallel=true, org.gradle.caching=true, and org.gradle.daemon=true to gradle.properties cut a 6-minute CI build down to under 3 minutes without touching any task logic.

Code Example:
```
# gradle.properties
org.gradle.daemon=true
org.gradle.parallel=true
org.gradle.caching=true
org.gradle.configuration-cache=true
org.gradle.jvmargs=-Xmx2g -XX:+UseParallelGC
```

Interview Tip:
A concise interview answer is:

"I'd start with the low-effort wins in gradle.properties: enable the daemon, parallel execution, and the build cache, then tune JVM heap and GC settings. Beyond that, I'd trim unnecessary dependencies and split large modules so Gradle can skip or parallelize more work, and use --scan or --profile to find the actual bottleneck before optimizing further."