diff --git a/jgvariant-core/pom.xml b/jgvariant-core/pom.xml
index 3409da7..a10fe3b 100644
--- a/jgvariant-core/pom.xml
+++ b/jgvariant-core/pom.xml
@@ -37,14 +37,17 @@
     <dependency>
       <groupId>com.google.errorprone</groupId>
       <artifactId>error_prone_annotations</artifactId>
+      <optional>true</optional>
     </dependency>
     <dependency>
       <groupId>org.jetbrains</groupId>
       <artifactId>annotations</artifactId>
+      <optional>true</optional>
     </dependency>
     <dependency>
       <groupId>org.apiguardian</groupId>
       <artifactId>apiguardian-api</artifactId>
+      <optional>true</optional>
     </dependency>
 
     <!-- Static analysis -->
diff --git a/jgvariant-core/src/main/java/module-info.java b/jgvariant-core/src/main/java/module-info.java
index 6b45af0..6a743ed 100644
--- a/jgvariant-core/src/main/java/module-info.java
+++ b/jgvariant-core/src/main/java/module-info.java
@@ -80,9 +80,9 @@
  * }
  */
 module eu.mulk.jgvariant.core {
-  requires com.google.errorprone.annotations;
-  requires org.jetbrains.annotations;
-  requires org.apiguardian.api;
+  requires static com.google.errorprone.annotations;
+  requires static org.apiguardian.api;
+  requires static org.jetbrains.annotations;
 
   exports eu.mulk.jgvariant.core;
 }