Nancy and IdentityServer4 in Net Core?

Great docs and samples for IdentityServer4 . And also for Nancy . But there are some issues with Nancy + IdentityServer4. Has anyone done this? When I add this to the API launch:

        app.UseIdentityServerAuthentication(new IdentityServerAuthenticationOptions
        {
            Authority = "http://localhost:55555",
            RequireHttpsMetadata = false,

            ApiName = "MyAPI"
        });

      

        
        
        
      

    

Unable to resolve UrlEncoder when starting service. Plus I'm not sure how to set up authorization requirements in Nancy modules. Any direction is appreciated.