public void Configure(IApplicationBuilder app, IProxyStateLookup lookup)
    {
        app.UseRouting();
        app.UseAuthorization();
        app.UseEndpoints(endpoints =>
        {
            endpoints.MapControllers();
            endpoints.MapReverseProxy(proxyPipeline =>
            {
                proxyPipeline.Use((context, next) =>
                {
                    if (lookup.TryGetCluster("cluster2", out var cluster))
                    {
                        var newDestinationId = "destination3";
                        var newDestinationConfig = new DestinationConfig {
                            Address = "https://127.0.0.1:123/abcd1234/",
                            Health = "http://127.0.0.1:1234/"
                        };

                        var reverseProxyFeature = context.Features.Get<IReverseProxyFeature>();
                        // key-value stored in Metadata to trigger update
                        if(reverseProxyFeature.AvailableDestinations.Any(x => x.Model.Config.Metadata?["key"] != null)) {
                            var destinationNew = new DestinationState(
                                newDestinationId,
                                new DestinationModel(newDestinationConfig)
                            );

                            cluster = new ClusterState("cluster3", new ClusterModel(
                                    new ClusterConfig {
                                        ClusterId = "cluster3",
                                        Destinations =
                                            new Dictionary<string, DestinationConfig>(StringComparer
                                                .OrdinalIgnoreCase) { { destinationNew.DestinationId, destinationNew.Model.Config } }
                                    },
                                    new HttpMessageInvoker(new HttpClientHandler())
                                )
                            );

                            cluster.DestinationsState = new ClusterDestinationsState(
                                reverseProxyFeature.AllDestinations,
                                new List<DestinationState> { destinationNew }
                            );

                            context.ReassignProxyRequest(cluster);
                        }
                    }

                    return next();
                });
                proxyPipeline.UseSessionAffinity();
                proxyPipeline.UseLoadBalancing();
            });
        });
    }