diff --git a/comm/tools/esmify/mach_commands.py b/comm/tools/esmify/mach_commands.py
index fb02f4..f1ce34 100644
--- a/comm/tools/esmify/mach_commands.py
+++ b/comm/tools/esmify/mach_commands.py
@@ -14,12 +14,12 @@
 
 def path_sep_to_native(path_str):
     """Make separators in the path OS native."""
-    return pathlib.os.sep.join(path_str.split("/"))
+    return os.sep.join(path_str.split("/"))
 
 
 def path_sep_from_native(path):
     """Make separators in the path OS native."""
-    return "/".join(str(path).split(pathlib.os.sep))
+    return "/".join(str(path).split(os.sep))
 
 
 excluded_from_convert_prefix = list(
diff --git a/tools/esmify/mach_commands.py b/tools/esmify/mach_commands.py
index 787de4..680801 100644
--- a/tools/esmify/mach_commands.py
+++ b/tools/esmify/mach_commands.py
@@ -15,12 +15,12 @@
 
 def path_sep_to_native(path_str):
     """Make separators in the path OS native."""
-    return pathlib.os.sep.join(path_str.split("/"))
+    return os.sep.join(path_str.split("/"))
 
 
 def path_sep_from_native(path):
     """Make separators in the path OS native."""
-    return "/".join(str(path).split(pathlib.os.sep))
+    return "/".join(str(path).split(os.sep))
 
 
 excluded_from_convert_prefix = list(