How can I do OneAppPerSuite in specs2?

My goal is to get an application running and execute multiple tests on the same instance of the app.

I have tried this solution without much luck. Here is my test:

class ApplicationSpec extends Specification { sequential


  object AppWithTestDb2 extends FakeApplication(additionalConfiguration = 
    Map(
    ("db.default.driver") -> "org.h2.Driver",
    ("db.default.url") -> (
//        "jdbc:h2:mem:play-test-" + scala.util.Random.nextInt +      // in memory database 
        "jdbc:h2:/tmp/play-test-" + scala.util.Random.nextInt +     // file based db that can be accessed using h2-browse in activator
        ";MODE=PostgreSQL;DATABASE_TO_UPPER=false;DB_CLOSE_DELAY=-1")
    ))

    running(AppWithTestDb2) {

      "Application" should {

        "send 404 on a bad request" in {
          route(FakeRequest(GET, "/boum")) must beNone
        }

        "post signup request" in {
          val res = route(FakeRequest(POST, "/user", FakeHeaders(), TestData.newUser)).get
                  status(res) must equalTo(OK)
                  contentType(res) must beSome("application/json")
                  contentAsJson(res) mustEqual TestData.newUser
        }

        "fail signup request for existing user" in {
          val res1 = route(FakeRequest(POST, "/user", FakeHeaders(), TestData.newUser)).get
                  Await.result(res1, Duration.Inf)
                  val res = route(FakeRequest(POST, "/user", FakeHeaders(), TestData.newUser)).get
                  Await.result(res, Duration.Inf)
                  status(res) must equalTo(CONFLICT)
                  contentType(res) must beSome("application/json")
                  contentAsJson(res) mustEqual TestData.newUser
        }

    }
  }

}

The problem here is that application starts and stops immediately and tests are executed without a running application:

[debug] c.j.b.BoneCPDataSource - JDBC URL = jdbc:h2:/tmp/play-test--437407884;MODE=PostgreSQL;DATABASE_TO_UPPER=false;DB_CLOSE_DELAY=-1, Username = zalando, partitions = 1, max (per partition) = 30, min (per partition) = 5, idle max age = 10 min, idle test period = 1 min, strategy = DEFAULT
[info] application - Application has started
[debug] application - Binding to Slick DAO implementations.
[info] application - Application shutdown...
[debug] c.j.b.BoneCPDataSource - Connection pool has been shut down
[info] ApplicationSpec
[info] 
[info] Application should
[info] ! send 404 on a bad request
[error]    RuntimeException: : There is no started application  (Play.scala:71)
[error] play.api.Play$$anonfun$current$1.apply(Play.scala:71)
[error] play.api.Play$$anonfun$current$1.apply(Play.scala:71)
[error] play.api.Play$.current(Play.scala:71)
[error] play.api.test.RouteInvokers$class.route(Helpers.scala:305)
[error] play.api.test.Helpers$.route(Helpers.scala:403)
[error] ApplicationSpec$$anonfun$1$$anonfun$apply$7$$anonfun$apply$8$$anonfun$apply$9.apply(ApplicationSpec.scala:76)
[error] ApplicationSpec$$anonfun$1$$anonfun$apply$7$$anonfun$apply$8$$anonfun$apply$9.apply(ApplicationSpec.scala:76)
[error] ApplicationSpec$$anonfun$1$$anonfun$apply$7$$anonfun$apply$8.apply(ApplicationSpec.scala:76)
[error] ApplicationSpec$$anonfun$1$$anonfun$apply$7$$anonfun$apply$8.apply(ApplicationSpec.scala:76)

I may also consider scalatest.