diff --git a/protobuf-nano/build.gradle b/protobuf-nano/build.gradle
index 7b5eea924d..1313e088cb 100644
--- a/protobuf-nano/build.gradle
+++ b/protobuf-nano/build.gradle
@@ -1,3 +1,7 @@
+plugins {
+    id "be.insaneprogramming.gradle.animalsniffer" version "1.4.0"
+}
+
 description = 'gRPC: Protobuf Nano'
 
 dependencies {
@@ -5,3 +9,7 @@ dependencies {
             libraries.protobuf_nano,
             libraries.guava
 }
+
+animalsniffer {
+    signature = "org.codehaus.mojo.signature:java16:+@signature"
+}
diff --git a/protobuf/build.gradle b/protobuf/build.gradle
index 2aa9d19b20..ba561abff0 100644
--- a/protobuf/build.gradle
+++ b/protobuf/build.gradle
@@ -1,3 +1,7 @@
+plugins {
+    id "be.insaneprogramming.gradle.animalsniffer" version "1.4.0"
+}
+
 description = 'gRPC: Protobuf'
 
 dependencies {
@@ -5,3 +9,7 @@ dependencies {
             libraries.protobuf,
             libraries.guava
 }
+
+animalsniffer {
+    signature = "org.codehaus.mojo.signature:java16:+@signature"
+}