diff --git a/CMakeLists.txt b/CMakeLists.txt
index e3f3f87a47c..45b4a0282f5 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -334,7 +334,7 @@ if(NOT (BUILD_STATIC_LIB AND BYN_INSTALL_TOOLS_ONLY))
     ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR})
 endif()
 if(NOT BYN_INSTALL_TOOLS_ONLY)
-  install(FILES src/binaryen-c.h src/wasm-delegations.h DESTINATION ${CMAKE_INSTALL_INCLUDEDIR})
+  install(FILES src/binaryen-c.h src/wasm-delegations.def DESTINATION ${CMAKE_INSTALL_INCLUDEDIR})
 endif()
 
 function(binaryen_add_executable name sources)
diff --git a/src/binaryen-c.cpp b/src/binaryen-c.cpp
index 56bb94b50ac..e6ef2a36672 100644
--- a/src/binaryen-c.cpp
+++ b/src/binaryen-c.cpp
@@ -185,7 +185,7 @@ BinaryenExpressionId BinaryenInvalidId(void) {
     return Expression::Id::CLASS_TO_VISIT##Id;                                 \
   }
 
-#include "wasm-delegations.h"
+#include "wasm-delegations.def"
 
 // External kinds
 
diff --git a/src/binaryen-c.h b/src/binaryen-c.h
index a4210a8db26..79613bd6592 100644
--- a/src/binaryen-c.h
+++ b/src/binaryen-c.h
@@ -130,7 +130,7 @@ BINARYEN_API BinaryenExpressionId BinaryenInvalidId(void);
 #define DELEGATE(CLASS_TO_VISIT)                                               \
   BINARYEN_API BinaryenExpressionId Binaryen##CLASS_TO_VISIT##Id(void);
 
-#include "wasm-delegations.h"
+#include "wasm-delegations.def"
 
 // External kinds (call to get the value of each; you can cache them)
 
diff --git a/src/ir/ExpressionAnalyzer.cpp b/src/ir/ExpressionAnalyzer.cpp
index 59f243e4d18..0c6081b03f1 100644
--- a/src/ir/ExpressionAnalyzer.cpp
+++ b/src/ir/ExpressionAnalyzer.cpp
@@ -230,7 +230,7 @@ bool ExpressionAnalyzer::flexibleEqual(Expression* left,
     }                                                                          \
   }
 
-#include "wasm-delegations-fields.h"
+#include "wasm-delegations-fields.def"
 
       return true;
     }
@@ -322,7 +322,7 @@ size_t ExpressionAnalyzer::hash(Expression* curr) {
 
 #define DELEGATE_FIELD_SCOPE_NAME_USE(id, name) visitScopeName(cast->name);
 
-#include "wasm-delegations-fields.h"
+#include "wasm-delegations-fields.def"
     }
 
     void noteScopeName(Name curr) {
diff --git a/src/ir/ExpressionManipulator.cpp b/src/ir/ExpressionManipulator.cpp
index 7ad8d0f505d..535aa51c3ac 100644
--- a/src/ir/ExpressionManipulator.cpp
+++ b/src/ir/ExpressionManipulator.cpp
@@ -101,7 +101,7 @@ flexibleCopy(Expression* original, Module& wasm, CustomCopier custom) {
 
 #define DELEGATE_FIELD_INT_ARRAY(id, name) COPY_ARRAY(name)
 
-#include "wasm-delegations-fields.h"
+#include "wasm-delegations-fields.def"
 
     // The type can be simply copied.
     copy->type = original->type;
diff --git a/src/ir/branch-utils.h b/src/ir/branch-utils.h
index 87f7813e7ee..54a3f1c168e 100644
--- a/src/ir/branch-utils.h
+++ b/src/ir/branch-utils.h
@@ -66,7 +66,7 @@ template<typename T> void operateOnScopeNameUses(Expression* expr, T func) {
 #define DELEGATE_FIELD_CHILD_VECTOR(id, name)
 #define DELEGATE_FIELD_INT_ARRAY(id, name)
 
-#include "wasm-delegations-fields.h"
+#include "wasm-delegations-fields.def"
 }
 
 // Similar to operateOnScopeNameUses, but also passes in the type that is sent
@@ -131,7 +131,7 @@ template<typename T> void operateOnScopeNameDefs(Expression* expr, T func) {
 #define DELEGATE_FIELD_SCOPE_NAME_USE(id, name)
 #define DELEGATE_FIELD_SCOPE_NAME_USE_VECTOR(id, name)
 
-#include "wasm-delegations-fields.h"
+#include "wasm-delegations-fields.def"
 }
 
 using NameSet = std::set<Name>;
diff --git a/src/ir/iteration.h b/src/ir/iteration.h
index a785fbc93f8..bfebf5a1601 100644
--- a/src/ir/iteration.h
+++ b/src/ir/iteration.h
@@ -101,7 +101,7 @@ template<class Specific> class AbstractChildIterator {
 #define DELEGATE_FIELD_TYPE(id, name)
 #define DELEGATE_FIELD_ADDRESS(id, name)
 
-#include "wasm-delegations-fields.h"
+#include "wasm-delegations-fields.def"
   }
 
   Iterator begin() const { return Iterator(*this, 0); }
diff --git a/src/ir/utils.h b/src/ir/utils.h
index 805844a7123..40f5aeb9a42 100644
--- a/src/ir/utils.h
+++ b/src/ir/utils.h
@@ -113,7 +113,7 @@ struct ReFinalize
 #define DELEGATE(CLASS_TO_VISIT)                                               \
   void visit##CLASS_TO_VISIT(CLASS_TO_VISIT* curr);
 
-#include "wasm-delegations.h"
+#include "wasm-delegations.def"
 
   void visitFunction(Function* curr);
 
@@ -139,7 +139,7 @@ struct ReFinalizeNode : public OverriddenVisitor<ReFinalizeNode> {
 #define DELEGATE(CLASS_TO_VISIT)                                               \
   void visit##CLASS_TO_VISIT(CLASS_TO_VISIT* curr) { curr->finalize(); }
 
-#include "wasm-delegations.h"
+#include "wasm-delegations.def"
 
   void visitExport(Export* curr) { WASM_UNREACHABLE("unimp"); }
   void visitGlobal(Global* curr) { WASM_UNREACHABLE("unimp"); }
diff --git a/src/wasm-delegations-fields.h b/src/wasm-delegations-fields.def
similarity index 100%
rename from src/wasm-delegations-fields.h
rename to src/wasm-delegations-fields.def
diff --git a/src/wasm-delegations.h b/src/wasm-delegations.def
similarity index 100%
rename from src/wasm-delegations.h
rename to src/wasm-delegations.def
diff --git a/src/wasm-stack.h b/src/wasm-stack.h
index f114bf43edd..13edc0138db 100644
--- a/src/wasm-stack.h
+++ b/src/wasm-stack.h
@@ -105,7 +105,7 @@ class BinaryInstWriter : public OverriddenVisitor<BinaryInstWriter> {
 #define DELEGATE(CLASS_TO_VISIT)                                               \
   void visit##CLASS_TO_VISIT(CLASS_TO_VISIT* curr);
 
-#include "wasm-delegations.h"
+#include "wasm-delegations.def"
 
   void emitResultType(Type type);
   void emitIfElse(If* curr);
diff --git a/src/wasm-traversal.h b/src/wasm-traversal.h
index eb91184e551..67177e848fc 100644
--- a/src/wasm-traversal.h
+++ b/src/wasm-traversal.h
@@ -41,7 +41,7 @@ template<typename SubType, typename ReturnType = void> struct Visitor {
   ReturnType visit##CLASS_TO_VISIT(CLASS_TO_VISIT* curr) {                     \
     return ReturnType();                                                       \
   }
-#include "wasm-delegations.h"
+#include "wasm-delegations.def"
 
   // Module-level visitors
   ReturnType visitExport(Export* curr) { return ReturnType(); }
@@ -62,7 +62,7 @@ template<typename SubType, typename ReturnType = void> struct Visitor {
     return static_cast<SubType*>(this)->visit##CLASS_TO_VISIT(                 \
       static_cast<CLASS_TO_VISIT*>(curr))
 
-#include "wasm-delegations.h"
+#include "wasm-delegations.def"
 
       default:
         WASM_UNREACHABLE("unexpected expression type");
@@ -84,7 +84,7 @@ struct OverriddenVisitor {
     WASM_UNREACHABLE("Derived class must implement visit" #CLASS_TO_VISIT);    \
   }
 
-#include "wasm-delegations.h"
+#include "wasm-delegations.def"
 
   ReturnType visit(Expression* curr) {
     assert(curr);
@@ -95,7 +95,7 @@ struct OverriddenVisitor {
     return static_cast<SubType*>(this)->visit##CLASS_TO_VISIT(                 \
       static_cast<CLASS_TO_VISIT*>(curr))
 
-#include "wasm-delegations.h"
+#include "wasm-delegations.def"
 
       default:
         WASM_UNREACHABLE("unexpected expression type");
@@ -117,7 +117,7 @@ struct UnifiedExpressionVisitor : public Visitor<SubType, ReturnType> {
     return static_cast<SubType*>(this)->visitExpression(curr);                 \
   }
 
-#include "wasm-delegations.h"
+#include "wasm-delegations.def"
 };
 
 //
@@ -327,7 +327,7 @@ struct Walker : public VisitorType {
     self->visit##CLASS_TO_VISIT((*currp)->cast<CLASS_TO_VISIT>());             \
   }
 
-#include "wasm-delegations.h"
+#include "wasm-delegations.def"
 
   void setModule(Module* module) { currModule = module; }
 
@@ -377,7 +377,7 @@ struct PostWalker : public Walker<SubType, VisitorType> {
 #define DELEGATE_FIELD_TYPE(id, name)
 #define DELEGATE_FIELD_ADDRESS(id, name)
 
-#include "wasm-delegations-fields.h"
+#include "wasm-delegations-fields.def"
   }
 };
 
diff --git a/src/wasm/wasm.cpp b/src/wasm/wasm.cpp
index b41f34ddfff..f769cb1f57d 100644
--- a/src/wasm/wasm.cpp
+++ b/src/wasm/wasm.cpp
@@ -110,7 +110,7 @@ const char* getExpressionName(Expression* curr) {
   case Expression::Id::CLASS_TO_VISIT##Id:                                     \
     return #CLASS_TO_VISIT;
 
-#include "wasm-delegations.h"
+#include "wasm-delegations.def"
 
     default:
       WASM_UNREACHABLE("invalid id");