diff --git a/src/header/ctype/cbindgen.toml b/src/header/ctype/cbindgen.toml
index 0f42238c8a..996da0abae 100644
--- a/src/header/ctype/cbindgen.toml
+++ b/src/header/ctype/cbindgen.toml
@@ -1,5 +1,6 @@
 sys_includes = ["bits/ctype.h", "features.h"]
 include_guard = "_RELIBC_CTYPE_H"
+after_includes = "#include <bits/locale-t.h> // for locale_t"
 language = "C"
 style = "Tag"
 no_includes = true