diff --git a/compiler/src/main/cpp/capnpc-java.c++ b/compiler/src/main/cpp/capnpc-java.c++
index 55c9b41..16ea0b0 100644
--- a/compiler/src/main/cpp/capnpc-java.c++
+++ b/compiler/src/main/cpp/capnpc-java.c++
@@ -104,8 +104,8 @@ void enumerateDeps(schema::Node::Reader node, std::set<uint64_t>& deps) {
     }
     case schema::Node::INTERFACE: {
       auto interfaceNode = node.getInterface();
-      for (auto extend: interfaceNode.getExtends()) {
-        deps.insert(extend);
+      for (auto superclass: interfaceNode.getSuperclasses()) {
+        deps.insert(superclass.getId());
       }
       for (auto method: interfaceNode.getMethods()) {
         deps.insert(method.getParamStructType());