diff --git a/testutils/build.gradle b/testutils/build.gradle
index 11a8d1b76e7..7f46a7cc1a3 100644
--- a/testutils/build.gradle
+++ b/testutils/build.gradle
@@ -20,6 +20,7 @@ dependencies {
     api 'androidx.test.ext:truth:' + androidxTestTruthVersion
     api 'junit:junit:' + junitVersion
     api 'com.google.truth:truth:' + truthVersion
+    api 'com.google.truth.extensions:truth-java8-extension:' + truthVersion
     compileOnly 'org.checkerframework:checker-qual:' + checkerframeworkVersion
     compileOnly 'org.checkerframework:checker-compat-qual:' + checkerframeworkCompatVersion
     compileOnly 'org.jetbrains.kotlin:kotlin-annotations-jvm:' + kotlinAnnotationsVersion