curryAndCompilerCurry.scala

// this is with POC (plain old curry)
// () => Filter
  val loginPostService = new ExceptionFilter andThen
    new ServiceFilter(serviceMatcher) andThen
    new SessionIdFilter(sessionStore) andThen
    new KeymasterLoginFilter(sessionStore) andThen
    new KeymasterIdentityProvider(keymasterClient, Path(keymasterIdentityProviderPath))

// (ServerConfig) => Filter

val loginPostService: ServerConfig => Filter = config => {
  new ExceptionFilter andThen
    new ServiceFilter(config.serviceMatcher) andThen
    new SessionIdFilter(config.sessionStore) andThen
    new KeymasterLoginFilter(config.sessionStore) andThen
    new KeymasterIdentityProvider(config.keymasterClient, Path(keymasterIdentityProviderPath))
}

 val routingService1: ServerConfig => RoutingService = config => {
   RoutingService.byMethodAndPathObject {
      case Method.Post -> Root / "login" => loginPostService(config)
      case Method.Get -> Root / "login" => loginGetService(config)
      case _ => allOtherRequests(config)
    }
  }
  
Httpx.serve(...., routingService1(config))

// when we have a smart compiler (no java, your compiler sucks)
// we can have the compiler do the work for us
// () => Filter
  val loginPostService = new ExceptionFilter andThen
    new ServiceFilter(serviceMatcher) andThen
    new SessionIdFilter(sessionStore) andThen
    new KeymasterLoginFilter(sessionStore) andThen
    new KeymasterIdentityProvider(keymasterClient, Path(keymasterIdentityProviderPath))

// (implicit ServerConfig) => Filter

def loginPostService(implicit config: ServerConfig): Filter = 
  new ExceptionFilter andThen
    new ServiceFilter(config.serviceMatcher) andThen
    new SessionIdFilter(config.sessionStore) andThen
    new KeymasterLoginFilter(config.sessionStore) andThen
    new KeymasterIdentityProvider(config.keymasterClient, Path(keymasterIdentityProviderPath))


 val routingService1(implicit config: ServerConfig): RoutingService =
   RoutingService.byMethodAndPathObject {
      case Method.Post -> Root / "login" => loginPostService(config)
      case Method.Get -> Root / "login" => loginGetService(config)
      case _ => allOtherRequests(config)
    }
implicit val config = ServerConfig(???, ???, ???, ???)
Httpx.serve(...., routingService1)

object ServerInstances {
  implicits ...
}

object BpApp extends TwitterServer {
  import ServerInstances._
}