I am getting a strange error on my code / repo when trying to run a EmberServer in http4s library. I have taken bits from their starter kit and just trying to run the same on my multi-module sbt project repo, rather than running on the sample project http4s provides as the Learner Starter Kit.

The same code is working on their repo / kit, but failing on my multi-module project. I am using Intellij Idea. The error is coming on the function <+> which is for some reason not being recognized.

I have double checked the versions and dependencyTree for the whole project, all libraries are same and referring to the same version jar in both the project repos. I am confused as to what could be the issue here.

/path/to/package/Http4sLearnerKitServer.scala:26:67
value <+> is not a member of org.http4s.HttpRoutes[F]
        Http4sLearnerKitRoutes.helloWorldRoutes[F](helloWorldAlg) <+>

Code:

object Http4sLearnerKitServer {

  def run[F[_]: Async: Network]: F[Nothing] = {
    for {
      client <- EmberClientBuilder.default[F].build
      helloWorldAlg = HelloWorld.impl[F]
      jokeAlg = Jokes.impl[F](client)

      // Combine Service Routes into an HttpApp.
      // Can also be done via a Router if you
      // want to extract segments not checked
      // in the underlying routes.
      httpApp = (
        Http4sLearnerKitRoutes.helloWorldRoutes[F](helloWorldAlg) <+>
        Http4sLearnerKitRoutes.jokeRoutes[F](jokeAlg)
      ).orNotFound

      // With Middlewares in place
      finalHttpApp = Logger.httpApp(logHeaders = true, logBody = true)(httpApp)

      _ <- 
        EmberServerBuilder.default[F]
          .withHost(ipv4"0.0.0.0")
          .withPort(port"8080")
          .withHttpApp(finalHttpApp)
          .build
    } yield ()
  }.useForever
}

• I have tried deleting the whole project and getting is again from Github.
• Tried the invalidate caches and restart.
• I tried adding certain libraries like typesafe config and scala logging to the starter / learner project. Added most of the libraries from the multi-module project that were having common jar tree, but still it works in one but doesn’t in the multi-module project repo.

Nothing seems to be working. Is there anything else I can check?