diff --git a/build.gradle b/build.gradle
index 5ea3ece..5bce484 100644
--- a/build.gradle
+++ b/build.gradle
@@ -10,7 +10,7 @@ dependencies {
     testImplementation("org.junit.jupiter:junit-jupiter-api:5.6.2")
     testImplementation("org.junit.jupiter:junit-jupiter-params:5.6.2")
     testImplementation("org.junit.jupiter:junit-jupiter-engine:5.6.2")
-    testImplementation("com.approvaltests:approvaltests:9.3.0")
+    testImplementation("com.approvaltests:approvaltests:18.5.0")
 }
 
 tasks.withType(JavaCompile) {