diff --git a/mailman_sync.py b/mailman_sync.py
index 44623ed..c599f90 100755
--- a/mailman_sync.py
+++ b/mailman_sync.py
@@ -16,11 +16,11 @@ Update Mailman 3 lists via a json API of the form:
 }
 """
 
-import argparse
 import json
 import os
 import email.utils
 
+import configargparse
 import mailmanclient
 import requests
 
@@ -207,8 +207,13 @@ def main(
 
 
 def parse_arguments():
-    argp = argparse.ArgumentParser(description=__doc__)
+    argp = configargparse.ArgumentParser(description=__doc__)
+    argp.add("-c", "--config", is_config_file=True, help="Config file path")
+
     argp.add_argument("--api", required=True, help="API endpoint to retrieve JSON from")
+    argp.add_argument(
+        "--api-auth", required=True, help="API Authorization header token"
+    )
 
     argp.add_argument("--mail-host", help="Base domain for all lists", required=True)
     argp.add_argument(
@@ -219,6 +224,9 @@ def parse_arguments():
     argp.add_argument(
         "--mailman-user", help="Username for Mailman3 REST API", default="restadmin"
     )
+    argp.add_argument(
+        "--mailman-pass", help="Password for Mailman3 REST API", required=True
+    )
 
     argp.add_argument(
         "--cf-auth-token", help="Auth token for CloudFlare API", required=True
@@ -249,20 +257,15 @@ def parse_arguments():
 if __name__ == "__main__":
     args = parse_arguments()
 
-    for env_var in ("API_AUTH", "MAILMAN_PASS"):
-        if env_var not in os.environ:
-            print(f"Missing {env_var} environment variable")
-            exit(-1)
-
     mailman_client = mailmanclient.Client(
         args.mailman_url + "/3.1",
         args.mailman_user,
-        os.environ["MAILMAN_PASS"],
+        args.mailman_pass,
     )
 
     main(
         args.api,
-        os.environ["API_AUTH"],
+        args.api_auth,
         mailman_client,
         args.dry_run,
         args.mail_host,
diff --git a/systemd/mailman_sync.service b/systemd/mailman_sync.service
index f578668..b6dc642 100644
--- a/systemd/mailman_sync.service
+++ b/systemd/mailman_sync.service
@@ -6,9 +6,4 @@ User=mailman
 Group=mailman
 Type=oneshot
 TimeoutStartSec=600
-EnvironmentFile=/opt/mailman-sync/env
-ExecStart=/usr/bin/python3 /opt/mailman-sync/mailman_sync.py \
-    --api https://paperwork.claremontmakerspace.org/api/v1/paperwork/department/mailing_lists.json \
-    --mail-host claremontmakerspace.org \
-    --mailman-url http://localhost:8001 \
-    --mailman-user restadmin
+ExecStart=/usr/bin/python3 /opt/mailman-sync/mailman_sync.py --config /opt/mailman-sync/config.yml