diff --git a/src/libstore/linux/fchmodat2-compat.hh b/src/libstore/linux/fchmodat2-compat.hh
index 42b3f3a35..907695c31 100644
--- a/src/libstore/linux/fchmodat2-compat.hh
+++ b/src/libstore/linux/fchmodat2-compat.hh
@@ -1,4 +1,5 @@
 #include "store-config-private.hh"
+#include <cstdint>
 
 /*
  * Determine the syscall number for `fchmodat2`.