if (platform == "jdk8alpn") {
  // Add alpn-boot on Java 8 so we can use HTTP/2 without a stable API.
  val alpnBootVersion = alpnBootVersion
  if (alpnBootVersion != null) {
    val alpnBootJar =
      configurations
        .detachedConfiguration(
          dependencies.create("org.mortbay.jetty.alpn:alpn-boot:$alpnBootVersion"),
        ).singleFile
    tasks.withType<Test> {
      jvmArgs("-Xbootclasspath/p:$alpnBootJar")
    }