diff --git a/src/header/sys_resource/cbindgen.toml b/src/header/sys_resource/cbindgen.toml
index 43b32e07c4..3d0766cec4 100644
--- a/src/header/sys_resource/cbindgen.toml
+++ b/src/header/sys_resource/cbindgen.toml
@@ -1,5 +1,7 @@
+# stdint.h needed for uint64_t due to rlim_t and constants u64
+# TODO POSIX says rlim_t can be unsigned int but including stdint.h is considered namespace pollution
 # sys/time.h brings in sys/select.h which brings in bits/timeval.h
-sys_includes = ["sys/time.h"]
+sys_includes = ["stdint.h", "sys/time.h"]
 after_includes = """
 #include <bits/id-t.h> // for id_t from sys/types.h
 """
diff --git a/src/header/threads/cbindgen.toml b/src/header/threads/cbindgen.toml
index 4e762f277d..da0c37e405 100644
--- a/src/header/threads/cbindgen.toml
+++ b/src/header/threads/cbindgen.toml
@@ -1,4 +1,6 @@
-sys_includes = []
+# time.h brings in features.h
+# features.h required for Rust never type (no return)
+sys_includes = ["time.h"]
 include_guard = "_RELIBC_THREADS_H"
 language = "C"
 style = "tag"