efcoreinmemoryfour.cs

public void ConfigureServices(IServiceCollection services)
{
    services.AddControllers();
    services.AddDbContext<StockNotificationContext>(options => options.UseInMemoryDatabase(databaseName: "StockNotification"));
    services.AddScoped<IUserSettingsService, UserSettingsService>();
}

public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
    // this should be here when you create the solution
    app.UseHttpsRedirection();
    app.UseRouting();
    app.UseAuthorization();
    app.UseEndpoints(endpoints =>
    {
        endpoints.MapControllers();
    });

    using (var serviceScope = app.ApplicationServices.CreateScope())
    {
        var dbContext = serviceScope.ServiceProvider.GetService<StockNotificationContext>();
        tblSellersBuilder.Initialize(dbContext);
    }
}