diff --git a/Userland/Libraries/LibC/Headers.cmake b/Userland/Libraries/LibC/Headers.cmake
index 7aff7b9f6d5..e7efd36f9a8 100644
--- a/Userland/Libraries/LibC/Headers.cmake
+++ b/Userland/Libraries/LibC/Headers.cmake
@@ -161,6 +161,7 @@ set(HEADERS
     ../../../Kernel/API/POSIX/ucontext.h
     ../../../Kernel/API/POSIX/termios.h
     ../../../Kernel/API/POSIX/signal.h
+    ../../../Kernel/API/POSIX/winsize.h
 
     ../../../Kernel/API/serenity_limits.h