diff --git a/relay/application.py b/relay/application.py
index c834598..ea65992 100644
--- a/relay/application.py
+++ b/relay/application.py
@@ -262,7 +262,7 @@ async def handle_response_headers(request: web.Request, handler: Coroutine) -> R
 	resp = await handler(request)
 	resp.headers['Server'] = 'ActivityRelay'
 
-	if request.app['dev'] and request.path.endswith(('.css', '.js')):
+	if not request.app['dev'] and request.path.endswith(('.css', '.js')):
 		resp.headers['Cache-Control'] = 'public,max-age=2628000,immutable'
 
 	else:
diff --git a/relay/manage.py b/relay/manage.py
index 63fc6db..796ec0b 100644
--- a/relay/manage.py
+++ b/relay/manage.py
@@ -217,7 +217,7 @@ def cli_run(ctx: click.Context, dev: bool = False) -> None:
 		click.echo(pip_command)
 		return
 
-	ctx.obj['dev'] = True
+	ctx.obj['dev'] = dev
 	ctx.obj.run()
 
 	# todo: figure out why the relay doesn't quit properly without this