diff --git a/.github/workflows/errorprone.yml b/.github/workflows/errorprone.yml
index a0111b86..81e287a5 100644
--- a/.github/workflows/errorprone.yml
+++ b/.github/workflows/errorprone.yml
@@ -11,4 +11,4 @@ jobs:
         with:
           fetch-depth: 10
       - name: Check
-        run: ./gradlew compileJava -PenableErrorProne
+        run: ./gradlew compileJava -PenableErrorProne -PWerror
diff --git a/build.gradle.kts b/build.gradle.kts
index 8d623f35..06491022 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -229,7 +229,10 @@ allprojects {
                 }
             }
             tasks.withType<JavaCompile>().configureEach {
-                options.compilerArgs.addAll(listOf("-Xmaxerrs", "10000", "-Xmaxwarns", "10000", "-Werror"))
+                options.compilerArgs.addAll(listOf("-Xmaxerrs", "10000", "-Xmaxwarns", "10000"))
+                if (props.bool("Werror", false)) {
+                    options.compilerArgs.add("-Werror")
+                }
                 options.errorprone {
                     errorproneArgs.add("-XepExcludedPaths:.*/javacc/.*")
                     disableWarningsInGeneratedCode.set(true)