public void ConfigureServices(IServiceCollection services)
{
    // make sure to add your queries and commands before the .AddPoweredSoftQueries and .AddPoweredSoftCommands
    AddQueries(services);
    AddCommands(services);

    // adds the non related to aspnet core features.
    services.AddPoweredSoftCQRS();
    
    services
        .AddControllers()
        .AddPoweredSoftQueries() // adds queries to aspnetcore mvc.(you can make it configurable to load balance only commands on a instance)
        .AddPoweredSoftCommands() // adds commands to aspnetcore mvc. (you can make it configurable to load balance only commands on a instance)
        .AddFluentValidation();

    // enabling gql.
    services
        .AddGraphQLServer()
        .AddProjections()
        .AddQueryType(d => d.Name("Query"))
        .AddPoweredSoftQueries()
        .AddPoweredSoftDynamicQueries()
        .AddMutationType(d => d.Name("Mutation"))
        .AddPoweredSoftMutations();

    services.AddSwaggerGen();
}

private void AddCommands(IServiceCollection services)
{
    services.AddCommand<CreatePersonCommand, CreatePersonCommandHandler>();
    services.AddTransient<IValidator<CreatePersonCommand>, CreatePersonCommandValidator>();

    services.AddCommand<EchoCommand, string, EchoCommandHandler>();
    services.AddTransient<IValidator<EchoCommand>, EchoCommandValidator>();
}

private void AddQueries(IServiceCollection services)
{
    services.AddQuery<PersonQuery, IQueryable<Person>, PersonQueryHandler>();
}

public void ConfigureServices(IServiceCollection services) 
{
    // without Package.
    services.AddCommand<EchoCommand, string, EchoCommandHandler>();
    services.AddTransient<IValidator<EchoCommand>, EchoCommandValidator>();
}

public void ConfigureServices(IServiceCollection services) 
{
    // with PoweredSoft.CQRS.FluentValidation package.
    services.AddCommandWithValidator<EchoCommand, string, EchoCommandHandler, EchoCommandValidator>();
}