diff --git a/themes.py b/themes.py
index 996f9c9f..30edcafc 100644
--- a/themes.py
+++ b/themes.py
@@ -1,9 +1,23 @@
 from os import listdir
 from os.path import isdir, isfile, join
 from json import dump,dumps, loads
-import argparse
+import subprocess
 
-def create_addons_json(sha):
+def get_shas(output):
+    """Returns a dict of CSS files and SHAs"""
+    output_lines = output.splitlines()
+    sha_dict = {}
+    for line in output_lines:
+        line = line.decode('utf-8').replace("\t","").split(" ")
+        sha = line[1]
+        css_file = [file for file in line[2].split("/") if "css" in file][0]
+        sha_dict.update({css_file: sha})
+    return(sha_dict)
+
+def create_addons_json():
+    addon_shas = subprocess.check_output(["git", "ls-files", "-s", "./CSS/addons/*.css"])
+    SHAS = get_shas(addon_shas)
+    print(SHAS)
     ADDONS = {"addons":{}}
     addon_root = './CSS/addons'
     addon_folders = [name for name in listdir(addon_root) if isdir(join(addon_root, name))]
@@ -20,7 +34,7 @@ def create_addons_json(sha):
             ADDONS["addons"].update({
                     app: {
                         addon: {
-                            "css": [f"https://{DOMAIN}/CSS/addons/{app}/{addon}/{file}?sha={sha}" for file in files if file.split(".")[1] == "css"]
+                            "css": [f"https://{DOMAIN}/CSS/addons/{app}/{addon}/{file}?sha={SHAS.get(file)}" for file in files if file.split(".")[1] == "css"]
                         }
                 }
             })
@@ -33,53 +47,51 @@ def create_addons_json(sha):
                     ADDONS["addons"][app].update({
                                 addon: {
                                     dir: {
-                                        "css": [f"https://{DOMAIN}/CSS/addons/{app}/{addon}/{dir}/{extra_file}?sha={sha}" for extra_file in extra_dir_files if extra_file.split(".")[1] == "css"]
+                                        "css": [f"https://{DOMAIN}/CSS/addons/{app}/{addon}/{dir}/{extra_file}?sha={SHAS.get(extra_file)}" for extra_file in extra_dir_files if extra_file.split(".")[1] == "css"]
                                     } for dir in extra_dirs
                                 }
                             })
     return dumps(ADDONS)
 
-def create_json(sha,app_folders:list=None,themes:list=None,no_sub_folders=False):
+def create_json(app_folders:list=None,themes:list=None,no_sub_folders=False):
     if no_sub_folders:
         THEMES = {}
+        theme_shas = subprocess.check_output(["git", "ls-files", "-s", "./CSS/variables/*.css"])
+        SHAS = get_shas(theme_shas)
         for theme in themes:
             THEMES.update({
                 "themes": {
                     theme.split(".")[0].capitalize(): {
-                        "url": f"https://{DOMAIN}/CSS/variables/{theme}?sha={sha}" 
+                        "url": f"https://{DOMAIN}/CSS/variables/{theme}?sha={SHAS.get(theme)}" 
                     }for theme in themes
                 }
             })
         return dumps(THEMES)
     else:
-        ADDONS = loads(create_addons_json(sha))
+        ADDONS = loads(create_addons_json())
         APPS = {"applications":{}}
+        app_shas = subprocess.check_output(["git", "ls-files", "-s", "./CSS/themes/*base.css"])
+        SHAS = get_shas(app_shas)
         for app in app_folders:
             APPS.update({
                 "applications":{
                     app: {
-                        "base_css": f"https://{DOMAIN}/CSS/themes/{app}/{app}-base.css?sha={sha}",
+                        "base_css": f"https://{DOMAIN}/CSS/themes/{app}/{app}-base.css?sha={SHAS.get(f'{app}-base.css')}",
                         "addons": ADDONS["addons"][app] if app in ADDONS["addons"] else {}
                         } for app in app_folders
                     }
                 }
             )
-        THEMES = loads(create_json(sha,themes=themes,no_sub_folders=True))
+        THEMES = loads(create_json(themes=themes,no_sub_folders=True))
         APPS.update(ADDONS)
         APPS.update(THEMES)
         return dumps(APPS)
 
 if __name__== "__main__":
-
-    parser = argparse.ArgumentParser("Creates a JSON file with some information on all applications and themes")
-    parser.add_argument("--sha", required=True, help="This is the commit SHA we use for 'versioning' on CSS files")
-    args = parser.parse_args()
-
-    sha = args.sha
     app_folders = [name for name in listdir('./CSS/themes') if isdir(join('./CSS/themes', name))]
     themes = [name for name in listdir('./CSS/variables') if isfile(join('./CSS/variables', name))]
     DOMAIN = open("CNAME","rt",closefd=True).readline()
-    apps = loads(create_json(sha,app_folders,themes))
+    apps = loads(create_json(app_folders,themes))
 
     with open("themes.json", "w") as outfile:
         dump(apps, outfile,indent=2)