diff --git a/src/jasper/modules/world/src/keel/typeconv.cpp b/src/jasper/modules/world/src/keel/typeconv.cpp
index 1322bf6..d2bedfc 100644
--- a/src/jasper/modules/world/src/keel/typeconv.cpp
+++ b/src/jasper/modules/world/src/keel/typeconv.cpp
@@ -8,7 +8,7 @@ namespace jasper::world {
 
 ox::Error convertWorldDocToWorldStatic(
 		keel::Context &kctx,
-		WorldDoc &src,
+		WorldDoc const &src,
 		WorldStatic &dst) noexcept {
 	return WorldStaticLoader{kctx, dst, src}.loadWorldStatic();
 }
diff --git a/src/jasper/modules/world/src/keel/typeconv.hpp b/src/jasper/modules/world/src/keel/typeconv.hpp
index f6c359a..78264ec 100644
--- a/src/jasper/modules/world/src/keel/typeconv.hpp
+++ b/src/jasper/modules/world/src/keel/typeconv.hpp
@@ -10,6 +10,6 @@
 
 namespace jasper::world {
 
-ox::Error convertWorldDocToWorldStatic(keel::Context &kctx, WorldDoc &src, WorldStatic &dst) noexcept;
+ox::Error convertWorldDocToWorldStatic(keel::Context &kctx, WorldDoc const &src, WorldStatic &dst) noexcept;
 
 }