fix the build for scala 3

build.sbt

@@ -100,6 +100,6 @@ lazy val root = (project in file("."))
           scalaStm,
           slf4jApi,
           slf4jSimple,
-          akkaHttp(scalaV.value).cross(CrossVersion.for3Use2_13),
-          akkaStream(scalaV.value).cross(CrossVersion.for3Use2_13)))
+          akkaHttp(scalaVersion.value).cross(CrossVersion.binary),
+          akkaStream(scalaVersion.value).cross(CrossVersion.binary)))
 

project/Dependencies.scala

@@ -1,4 +1,4 @@
-import sbt._
+import sbt.*
 
 object Dependencies {
   lazy val Examples = config("example") extend Compile
@@ -14,10 +14,10 @@ object Dependencies {
 
   object akkaHttp {
 
-    def apply(scalaVer: ScalaVer) = {
-      val v = scalaVer match {
-        case ScalaVer._211 => "10.1.9"
-        case _             => "10.2.6"
+    def apply(scalaVer: String): ModuleID = {
+      val v = ScalaVer.fromString(scalaVer) match {
+        case Some(ScalaVer._211) => "10.1.9"
+        case _                   => "10.5.3"
 
       }
 
@@ -26,10 +26,10 @@ object Dependencies {
   }
 
   object akkaStream {
-    def apply(scalaVer: ScalaVer) = {
-      val v = scalaVer match {
-        case ScalaVer._211 => "2.5.32"
-        case _             => "2.6.16"
+    def apply(scalaVer: String): ModuleID = {
+      val v = ScalaVer.fromString(scalaVer) match {
+        case Some(ScalaVer._211) => "2.5.32"
+        case _                   => "2.8.5"
       }
 
       "com.typesafe.akka" %% "akka-stream" % v % Test

project/ScalaVer.scala

@@ -1,5 +1,6 @@
 import sbt.Keys.{crossScalaVersions, scalaVersion}
-import sbt.settingKey
+import sbt.librarymanagement.CrossVersion
+import sbt.{Def, settingKey}
 
 sealed abstract class ScalaVer(val full: String)
 
@@ -19,17 +20,17 @@ object ScalaVer {
 
   def fromEnv: Option[ScalaVer] = sys.env.get("SCALA_VER") flatMap fromString
 
-  def fromString(full: String): Option[ScalaVer] = full match {
-    case x if x startsWith "2.11" => Some(_211)
-    case x if x startsWith "2.12" => Some(_212)
-    case x if x startsWith "2.13" => Some(_213)
-    case x if x startsWith "3.0"  => Some(_300)
-    case _                        => None
+  def fromString(full: String): Option[ScalaVer] = CrossVersion.partialVersion(full) match {
+    case Some((2, 11)) => Some(_211)
+    case Some((2, 12)) => Some(_212)
+    case Some((2, 13)) => Some(_213)
+    case Some((3, _))  => Some(_300)
+    case _             => None
   }
 
   lazy val scalaV = settingKey[ScalaVer]("Current Scala Version")
 
-  def settings = Seq(
+  def settings: Seq[Def.Setting[? >: String & Seq[String] & ScalaVer <: Object]] = Seq(
     scalaVersion        := (ScalaVer.fromEnv getOrElse ScalaVer.default).full,
     crossScalaVersions  := ScalaVer.values.map(_.full),
     scalaV              := ScalaVer.fromString(scalaVersion.value) getOrElse ScalaVer.default)