# Microsoft.AspNetCore.Routing

``` diff
 namespace Microsoft.AspNetCore.Routing {
     public sealed class RouteEndpointBuilder : EndpointBuilder {
-        public RouteEndpointBuilder(RequestDelegate requestDelegate, RoutePattern routePattern, int order);
+        public RouteEndpointBuilder(RequestDelegate? requestDelegate, RoutePattern routePattern, int order);
     }
 }
```

