diff --git a/installation/relay.service b/installation/relay.service
index 0325316..cf9fa6a 100644
--- a/installation/relay.service
+++ b/installation/relay.service
@@ -4,6 +4,7 @@ Description=ActivityPub Relay
 [Service]
 WorkingDirectory=/home/relay/relay
 ExecStart=/usr/bin/python3 -m relay run
+Environment="IS_SYSTEMD=1"
 
 [Install]
 WantedBy=multi-user.target
diff --git a/relay/logger.py b/relay/logger.py
index b8ff918..9729eb2 100644
--- a/relay/logger.py
+++ b/relay/logger.py
@@ -87,7 +87,7 @@ handlers: list[Any] = [logging.StreamHandler()]
 if env_log_file:
 	handlers.append(logging.FileHandler(env_log_file))
 
-if os.environ.get('INVOCATION_ID'):
+if os.environ.get('IS_SYSTEMD'):
 	logging_format = '%(levelname)s: %(message)s'
 
 else: