diff --git a/src/olympic/studio/applib/src/subcommands/change-format/change-format.hpp b/src/olympic/studio/applib/src/subcommands/change-format/change-format.hpp
index 7fc1f695..2f1aa93b 100644
--- a/src/olympic/studio/applib/src/subcommands/change-format/change-format.hpp
+++ b/src/olympic/studio/applib/src/subcommands/change-format/change-format.hpp
@@ -4,6 +4,8 @@
 
 #pragma once
 
+#include <studio/project.hpp>
+
 namespace studio {
 
 ox::Error cmdChangeFormat(Project &project, ox::SpanView<ox::CString> args) noexcept;