diff --git a/.gitmodules b/.gitmodules
index 918cb79e..08dc5599 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -10,3 +10,6 @@
 [submodule "asm-differ"]
 	path = tools/asm-differ
 	url = https://github.com/simonlindholm/asm-differ
+[submodule "lib/EventFlow"]
+	path = lib/EventFlow
+	url = https://github.com/open-ead/EventFlow
diff --git a/CMakeLists.txt b/CMakeLists.txt
index dd2d9332..91a53ea0 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -29,4 +29,7 @@ target_link_libraries(uking PUBLIC sead)
 add_subdirectory(lib/agl)
 target_link_libraries(uking PUBLIC agl)
 
+add_subdirectory(lib/EventFlow)
+target_link_libraries(uking PRIVATE evfl)
+
 add_subdirectory(src)
diff --git a/lib/EventFlow b/lib/EventFlow
new file mode 160000
index 00000000..8d138e1b
--- /dev/null
+++ b/lib/EventFlow
@@ -0,0 +1 @@
+Subproject commit 8d138e1b808250b14a87ca6339d79e6292000abe
diff --git a/src/KingSystem/ActorSystem/actAiQuery.h b/src/KingSystem/ActorSystem/actAiQuery.h
index 786a036f..e435777d 100644
--- a/src/KingSystem/ActorSystem/actAiQuery.h
+++ b/src/KingSystem/ActorSystem/actAiQuery.h
@@ -8,7 +8,7 @@
 
 namespace evfl {
 class ParamAccessor;
-class QueryArg;
+struct QueryArg;
 }  // namespace evfl
 
 namespace ksys::act {