Program.cs

using Microsoft.AspNetCore.Hosting;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.Hosting;
using Microsoft.Extensions.Logging;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;

namespace DMPackageManager.Website {
    public class Program {
        public static void Main(string[] args) {
            CreateHostBuilder(args).ConfigureAppConfiguration((hostContext, builder) => {
                if (hostContext.HostingEnvironment.IsDevelopment()) {
                        builder.AddUserSecrets<Program>();
                    }
                }).Build().Run();
        }

        public static IHostBuilder CreateHostBuilder(string[] args) =>
            Host.CreateDefaultBuilder(args)
                .ConfigureWebHostDefaults(webBuilder => {
                    webBuilder.UseStartup<Startup>();
                });
    }
}