diff --git a/python/py_vapid/__init__.py b/python/py_vapid/__init__.py
index 9d61e9d..76edc62 100644
--- a/python/py_vapid/__init__.py
+++ b/python/py_vapid/__init__.py
@@ -261,7 +261,7 @@ def verify_token(self, validation_token, verification_token):
     def _base_sign(self, claims):
         cclaims = copy.deepcopy(claims)
         if not cclaims.get('exp'):
-            cclaims['exp'] = str(int(time.time()) + 86400)
+            cclaims['exp'] = int(time.time()) + 86400
         if not self.conf.get('no-strict', False):
             valid = _check_sub(cclaims.get('sub', ''))
         else:
@@ -277,7 +277,6 @@ def _base_sign(self, claims):
                 "Missing 'aud' from claims. "
                 "'aud' is the scheme, host and optional port for this "
                 "transaction e.g. https://example.com:8080")
-
         return cclaims
 
     def sign(self, claims, crypto_key=None):
diff --git a/python/py_vapid/main.py b/python/py_vapid/main.py
index 54aa3e8..58ca491 100644
--- a/python/py_vapid/main.py
+++ b/python/py_vapid/main.py
@@ -36,15 +36,17 @@ def main():
     parser.add_argument('--applicationServerKey',
                         help="show applicationServerKey value",
                         default=False, action="store_true")
+    parser.add_argument('--private-key', '-k', help='private key pem file',
+                        default="private_key.pem")
     args = parser.parse_args()
 
     # Added to solve 2.7 => 3.* incompatibility
     Vapid = Vapid02
     if args.version1:
         Vapid = Vapid01
-    if args.gen or not os.path.exists('private_key.pem'):
+    if args.gen or not os.path.exists(args.private_key):
         if not args.gen:
-            print("No private_key.pem file found.")
+            print("No private key file found.")
             answer = None
             while answer not in ['y', 'n']:
                 answer = prompt("Do you want me to create one for you? (Y/n)")
@@ -60,7 +62,7 @@ def main():
         vapid.save_key('private_key.pem')
         print("Generating public_key.pem")
         vapid.save_public_key('public_key.pem')
-    vapid = Vapid.from_file('private_key.pem')
+    vapid = Vapid.from_file(args.private_key)
     claim_file = args.sign
     result = dict()
     if args.applicationServerKey:
diff --git a/python/setup.py b/python/setup.py
index f567a3d..1600cbc 100644
--- a/python/setup.py
+++ b/python/setup.py
@@ -3,7 +3,7 @@
 
 from setuptools import setup, find_packages
 
-__version__ = "1.8.2"
+__version__ = "1.9.0"
 
 
 def read_from(file):
diff --git a/rust/vapid/Cargo.toml b/rust/vapid/Cargo.toml
index 4ae33c7..6dabaff 100644
--- a/rust/vapid/Cargo.toml
+++ b/rust/vapid/Cargo.toml
@@ -1,8 +1,8 @@
 [package]
 name = "vapid"
-version = "0.4.0"
+version = "0.5.0"
 authors = ["jrconlin <jconlin+git@mozilla.com>"]
-edition = "2018"
+edition = "2021"
 description = "An implementation of the RFC 8292 Voluntary Application Server Identification (VAPID) Auth header generator"
 repository = "https://github.com/web-push-libs/vapid"
 license = "MPL 2.0"