diff --git a/build.sbt b/build.sbt
index 7c81a4c5..a0a3fd81 100644
--- a/build.sbt
+++ b/build.sbt
@@ -5,7 +5,7 @@ organization := "com.earldouglas"
 sbtPlugin := true
 scalacOptions ++= Seq("-feature", "-deprecation")
 scalaVersion := "2.12.20"
-crossScalaVersions += "3.3.4"
+crossScalaVersions += "3.5.1"
 pluginCrossBuild / sbtVersion := {
   scalaBinaryVersion.value match {
     case "2.12" => (pluginCrossBuild / sbtVersion).value
diff --git a/src/main/scala-2/com/earldouglas/sbt/war/Compat.scala b/src/main/scala-2/com/earldouglas/sbt/war/Compat.scala
index 254b5900..c51ad1d8 100644
--- a/src/main/scala-2/com/earldouglas/sbt/war/Compat.scala
+++ b/src/main/scala-2/com/earldouglas/sbt/war/Compat.scala
@@ -1,13 +1,35 @@
 package com.earldouglas.sbt.war
 
+import sbt.Def.Initialize
 import sbt.Keys._
 import sbt.Keys.{`package` => pkg}
 import sbt._
 
+import java.io.{File => JavaFile}
+
 object Compat {
+
   val Compile_pkg_artifact = Compile / pkg / artifact
   val Compile_sourceDirectory = Compile / sourceDirectory
   val Compile_target = Compile / target
   val Global_onLoad = Global / onLoad
   val pkg_artifact = pkg / artifact
+
+  val webappContents: Initialize[Task[Map[String, JavaFile]]] =
+    WebappComponentsPlugin.webappContents
+
+  def managedJars(config: Configuration): Initialize[Task[Seq[File]]] =
+    Def.task {
+      Classpaths
+        .managedJars(config, classpathTypes.value, update.value)
+        .map(_.data)
+        .toSeq
+    }
+
+  def toFile(file: TaskKey[File]): Initialize[Task[File]] =
+    file
+
+  val classpathFiles: Initialize[Task[Seq[File]]] =
+    (Runtime / fullClasspath)
+      .map(_.files)
 }
diff --git a/src/main/scala-2/com/earldouglas/sbt/war/WarPackagePluginCompat.scala b/src/main/scala-2/com/earldouglas/sbt/war/WarPackagePluginCompat.scala
deleted file mode 100644
index 609235ed..00000000
--- a/src/main/scala-2/com/earldouglas/sbt/war/WarPackagePluginCompat.scala
+++ /dev/null
@@ -1,17 +0,0 @@
-package com.earldouglas.sbt.war
-
-import sbt.Def.Initialize
-import sbt._
-
-object WarPackagePluginCompat {
-
-  // Flip webappContents around from (dst -> src) to (src -> dst)
-  lazy val packageContents
-      : Initialize[Task[Seq[(java.io.File, String)]]] =
-    WebappComponentsPlugin.webappContents
-      .map {
-        _.map {
-          _.swap
-        }.toSeq
-      }
-}
diff --git a/src/main/scala-2/com/earldouglas/sbt/war/WarPackageRunnerPluginCompat.scala b/src/main/scala-2/com/earldouglas/sbt/war/WarPackageRunnerPluginCompat.scala
deleted file mode 100644
index 844f6fc0..00000000
--- a/src/main/scala-2/com/earldouglas/sbt/war/WarPackageRunnerPluginCompat.scala
+++ /dev/null
@@ -1,19 +0,0 @@
-package com.earldouglas.sbt.war
-
-import sbt.Def.Initialize
-import sbt.Keys._
-import sbt._
-
-object WarPackageRunnerPluginCompat {
-
-  def runnerJars(config: Configuration): Initialize[Task[Seq[File]]] =
-    Def.task {
-      Classpaths
-        .managedJars(config, classpathTypes.value, update.value)
-        .map(_.data)
-        .toSeq
-    }
-
-  def toFile(file: TaskKey[File]): Initialize[Task[File]] =
-    file
-}
diff --git a/src/main/scala-2/com/earldouglas/sbt/war/WebappComponentsPluginCompat.scala b/src/main/scala-2/com/earldouglas/sbt/war/WebappComponentsPluginCompat.scala
deleted file mode 100644
index 2f87011a..00000000
--- a/src/main/scala-2/com/earldouglas/sbt/war/WebappComponentsPluginCompat.scala
+++ /dev/null
@@ -1,12 +0,0 @@
-package com.earldouglas.sbt.war
-
-import sbt.Def.Initialize
-import sbt.Keys._
-import sbt._
-
-object WebappComponentsPluginCompat {
-
-  val classpathFiles: Initialize[Task[Seq[File]]] =
-    (Runtime / fullClasspath)
-      .map(_.files)
-}
diff --git a/src/main/scala-2/com/earldouglas/sbt/war/WebappPackageRunnerPluginCompat.scala b/src/main/scala-2/com/earldouglas/sbt/war/WebappPackageRunnerPluginCompat.scala
deleted file mode 100644
index 9d058096..00000000
--- a/src/main/scala-2/com/earldouglas/sbt/war/WebappPackageRunnerPluginCompat.scala
+++ /dev/null
@@ -1,16 +0,0 @@
-package com.earldouglas.sbt.war
-
-import sbt.Def.Initialize
-import sbt.Keys._
-import sbt._
-
-object WebappPackageRunnerPluginCompat {
-
-  def runnerJars(config: Configuration): Initialize[Task[Seq[File]]] =
-    Def.task {
-      Classpaths
-        .managedJars(config, classpathTypes.value, update.value)
-        .map(_.data)
-        .toSeq
-    }
-}
diff --git a/src/main/scala-3/com/earldouglas/sbt/war/Compat.scala b/src/main/scala-3/com/earldouglas/sbt/war/Compat.scala
index a2f326f9..75bcc729 100644
--- a/src/main/scala-3/com/earldouglas/sbt/war/Compat.scala
+++ b/src/main/scala-3/com/earldouglas/sbt/war/Compat.scala
@@ -4,13 +4,48 @@ import sbt.Keys._
 import sbt.Keys.{`package` => pkg}
 import sbt._
 import sbt.given
+import sbt.Def.Initialize
+import sbt.Keys._
+import sbt.Keys.{`package` => pkg}
+import sbt._
+
+import java.io.{File => JavaFile}
 
 import scala.language.implicitConversions
 
-object Compat {
+object Compat:
+
   val Compile_pkg_artifact = Compile / pkg / artifact
   val Compile_sourceDirectory = Compile / sourceDirectory
   val Compile_target = Compile / target
   val Global_onLoad = Global / onLoad
   val pkg_artifact = pkg / artifact
-}
+
+  val webappContents: Initialize[Task[Map[String, HashedVirtualFileRef]]] =
+    Def.task:
+      val conv: FileConverter = fileConverter.value
+      WebappComponentsPlugin.webappContents.value
+        .map:
+          case (dst, src) => dst -> conv.toVirtualFile(src.toPath())
+
+  def managedJars(config: Configuration): Initialize[Task[Seq[File]]] =
+    Def.task:
+        Classpaths
+          .managedJars(config, classpathTypes.value, update.value, fileConverter.value)
+          .map(_.data)
+          .map(fileConverter.value.toPath(_))
+          .map(_.toFile())
+          .toList
+
+  def toFile(file: TaskKey[HashedVirtualFileRef]): Initialize[Task[File]] =
+    Def.task:
+      fileConverter.value
+        .toPath(file.value)
+        .toFile()
+
+  val classpathFiles: Initialize[Task[Seq[File]]] =
+      Def.task:
+        (Runtime / fullClasspath).value
+          .map(_.data)
+          .map(fileConverter.value.toPath(_))
+          .map(_.toFile())
diff --git a/src/main/scala-3/com/earldouglas/sbt/war/WarPackagePluginCompat.scala b/src/main/scala-3/com/earldouglas/sbt/war/WarPackagePluginCompat.scala
deleted file mode 100644
index 4954a509..00000000
--- a/src/main/scala-3/com/earldouglas/sbt/war/WarPackagePluginCompat.scala
+++ /dev/null
@@ -1,26 +0,0 @@
-package com.earldouglas.sbt.war
-
-import sbt.Def.Initialize
-import sbt.Keys.artifact
-import sbt.Keys.fileConverter
-import sbt.Keys.moduleName
-import sbt.Keys.{`package` => pkg}
-import sbt.*
-import sbt.given
-import scala.language.implicitConversions
-import java.nio.file.{ Path => NioPath }
-import xsbti.{ FileConverter, HashedVirtualFileRef, VirtualFile }
-import sbt.librarymanagement.Configuration
-import sbt.SlashSyntax.RichConfiguration
-
-object WarPackagePluginCompat:
-
-  // Flip webappContents around from (dst -> src) to (src -> dst)
-  def packageContents: Initialize[Task[Seq[(HashedVirtualFileRef, String)]]] =
-    Def.task:
-      val conv: FileConverter = fileConverter.value
-      WebappComponentsPlugin.webappContents.value
-        .map:
-            case (dst, src) => (conv.toVirtualFile(src.toPath()), dst)
-        .toSeq
-
diff --git a/src/main/scala-3/com/earldouglas/sbt/war/WarPackageRunnerPluginCompat.scala b/src/main/scala-3/com/earldouglas/sbt/war/WarPackageRunnerPluginCompat.scala
deleted file mode 100644
index ec2a7ef4..00000000
--- a/src/main/scala-3/com/earldouglas/sbt/war/WarPackageRunnerPluginCompat.scala
+++ /dev/null
@@ -1,28 +0,0 @@
-package com.earldouglas.sbt.war
-
-import sbt.Def.Initialize
-import sbt.Keys._
-import sbt.*
-import sbt.given
-import scala.language.implicitConversions
-import sbt.internal.util.Attributed
-import sbt.librarymanagement.Configuration
-import sbt.SlashSyntax.RichConfiguration
-import xsbti.HashedVirtualFileRef
-
-object WarPackageRunnerPluginCompat:
-
-    def runnerJars(config: Configuration): Initialize[Task[Seq[File]]] =
-      Def.task:
-          Classpaths
-            .managedJars(config, classpathTypes.value, update.value, fileConverter.value)
-            .map(_.data)
-            .map(fileConverter.value.toPath(_))
-            .map(_.toFile())
-            .toList
-
-    def toFile(file: TaskKey[HashedVirtualFileRef]): Initialize[Task[File]] =
-      Def.task:
-        fileConverter.value
-          .toPath(file.value)
-          .toFile()
diff --git a/src/main/scala-3/com/earldouglas/sbt/war/WebappComponentsPluginCompat.scala b/src/main/scala-3/com/earldouglas/sbt/war/WebappComponentsPluginCompat.scala
deleted file mode 100644
index 1b01801c..00000000
--- a/src/main/scala-3/com/earldouglas/sbt/war/WebappComponentsPluginCompat.scala
+++ /dev/null
@@ -1,18 +0,0 @@
-package com.earldouglas.sbt.war
-
-import sbt.Def.Initialize
-import sbt.Keys._
-import sbt.*
-import sbt.given
-import scala.language.implicitConversions
-import sbt.librarymanagement.Configuration
-import sbt.SlashSyntax.RichConfiguration
-
-object WebappComponentsPluginCompat:
-
-  lazy val classpathFiles: Initialize[Task[Seq[File]]] =
-      Def.task:
-        (Runtime / fullClasspath).value
-          .map(_.data)
-          .map(fileConverter.value.toPath(_))
-          .map(_.toFile())
diff --git a/src/main/scala-3/com/earldouglas/sbt/war/WebappPackageRunnerPluginCompat.scala b/src/main/scala-3/com/earldouglas/sbt/war/WebappPackageRunnerPluginCompat.scala
deleted file mode 100644
index f67cac7d..00000000
--- a/src/main/scala-3/com/earldouglas/sbt/war/WebappPackageRunnerPluginCompat.scala
+++ /dev/null
@@ -1,23 +0,0 @@
-package com.earldouglas.sbt.war
-
-import sbt.Def.Initialize
-import sbt.Keys.*
-import sbt.*
-import sbt.given
-import scala.language.implicitConversions
-import xsbti.HashedVirtualFileRef
-
-object WebappPackageRunnerPluginCompat:
-
-    def runnerJars(config: Configuration): Initialize[Task[Seq[File]]] =
-      Def.task:
-          Classpaths
-            .managedJars(config, classpathTypes.value, update.value, fileConverter.value)
-            .map(_.data)
-            .map(fileConverter.value.toPath(_))
-            .map(_.toFile())
-            .toList
-
-    def toFilePath(file: HashedVirtualFileRef): Initialize[Task[String]] =
-      Def.task:
-        fileConverter.value.toPath(file).toString()
diff --git a/src/main/scala/com/earldouglas/sbt/war/WarPackagePlugin.scala b/src/main/scala/com/earldouglas/sbt/war/WarPackagePlugin.scala
index 48f3ce7b..cb16a3cf 100644
--- a/src/main/scala/com/earldouglas/sbt/war/WarPackagePlugin.scala
+++ b/src/main/scala/com/earldouglas/sbt/war/WarPackagePlugin.scala
@@ -1,5 +1,4 @@
 package com.earldouglas.sbt.war
-
 import sbt.Keys._
 import sbt.Keys.{`package` => pkg}
 import sbt._
@@ -18,11 +17,12 @@ object WarPackagePlugin extends AutoPlugin {
 
   override lazy val projectSettings: Seq[Setting[_]] = {
 
+    // Flip webappContents around from (dst -> src) to (src -> dst)
+    val packageContents =
+      Compat.webappContents.map(_.map(_.swap).toSeq)
+
     val packageTaskSettings: Seq[Setting[_]] =
-      Defaults.packageTaskSettings(
-        pkg,
-        WarPackagePluginCompat.packageContents
-      )
+      Defaults.packageTaskSettings(pkg, packageContents)
 
     val packageArtifactSetting: Setting[_] =
       Compat.pkg_artifact := Artifact(moduleName.value, "war", "war")
diff --git a/src/main/scala/com/earldouglas/sbt/war/WarPackageRunnerPlugin.scala b/src/main/scala/com/earldouglas/sbt/war/WarPackageRunnerPlugin.scala
index 61d4e8cc..159d7c8c 100644
--- a/src/main/scala/com/earldouglas/sbt/war/WarPackageRunnerPlugin.scala
+++ b/src/main/scala/com/earldouglas/sbt/war/WarPackageRunnerPlugin.scala
@@ -47,7 +47,7 @@ object WarPackageRunnerPlugin extends AutoPlugin {
         stopContainerInstance()
 
         val runnerJars: Seq[File] =
-          WarPackageRunnerPluginCompat.runnerJars(War).value
+          Compat.managedJars(War).value
 
         runnerJars match {
           case runner :: Nil =>
@@ -60,7 +60,7 @@ object WarPackageRunnerPlugin extends AutoPlugin {
                   runner.getPath(),
                   "--port",
                   warPort.value.toString(),
-                  WarPackageRunnerPluginCompat
+                  Compat
                     .toFile(pkg)
                     .value
                     .getPath()
diff --git a/src/main/scala/com/earldouglas/sbt/war/WebappComponentsPlugin.scala b/src/main/scala/com/earldouglas/sbt/war/WebappComponentsPlugin.scala
index 456c3b8d..217b9c2f 100644
--- a/src/main/scala/com/earldouglas/sbt/war/WebappComponentsPlugin.scala
+++ b/src/main/scala/com/earldouglas/sbt/war/WebappComponentsPlugin.scala
@@ -51,16 +51,16 @@ object WebappComponentsPlugin extends AutoPlugin {
   override val projectSettings: Seq[Setting[_]] = {
 
     val webappResourcesTask: Initialize[Task[Map[String, File]]] =
-      (Compat.Compile_sourceDirectory)
+      Compat.Compile_sourceDirectory
         .map(_ / "webapp")
         .map(WebappComponents.getResources(_))
 
     val webappClassesTask: Initialize[Task[Map[String, File]]] =
-      WebappComponentsPluginCompat.classpathFiles
+      Compat.classpathFiles
         .map(WebappComponents.getClasses(_))
 
     val webappLibTask: Initialize[Task[Map[String, File]]] =
-      WebappComponentsPluginCompat.classpathFiles
+      Compat.classpathFiles
         .map(WebappComponents.getLib(_))
 
     Seq(
diff --git a/src/main/scala/com/earldouglas/sbt/war/WebappComponentsRunnerPlugin.scala b/src/main/scala/com/earldouglas/sbt/war/WebappComponentsRunnerPlugin.scala
index 4cbba8a9..51d95eb0 100644
--- a/src/main/scala/com/earldouglas/sbt/war/WebappComponentsRunnerPlugin.scala
+++ b/src/main/scala/com/earldouglas/sbt/war/WebappComponentsRunnerPlugin.scala
@@ -81,7 +81,7 @@ object WebappComponentsRunnerPlugin extends AutoPlugin {
         stopContainerInstance()
 
         val runnerJars: Seq[File] =
-          WebappPackageRunnerPluginCompat.runnerJars(Webapp).value
+          Compat.managedJars(Webapp).value
 
         streams.value.log.info("[sbt-war] Starting server")
         val process: ScalaProcess =
diff --git a/src/test/scala-2/com/earldouglas/sbt/war/TestCompat.scala b/src/test/scala-2/com/earldouglas/sbt/war/TestCompat.scala
new file mode 100644
index 00000000..5dc478f7
--- /dev/null
+++ b/src/test/scala-2/com/earldouglas/sbt/war/TestCompat.scala
@@ -0,0 +1,13 @@
+package com.earldouglas.sbt.war
+import java.util.{List => JavaList}
+import java.util.{Map => JavaMap}
+import scala.collection.JavaConverters._
+
+object TestCompat {
+
+  def asScala[A, B](javaMap: JavaMap[A, B]): Map[A, B] =
+    javaMap.asScala.toMap
+
+  def asScala[A](javaList: JavaList[A]): List[A] =
+    javaList.asScala.toList
+}
diff --git a/src/test/scala-3/com/earldouglas/sbt/war/TestCompat.scala b/src/test/scala-3/com/earldouglas/sbt/war/TestCompat.scala
new file mode 100644
index 00000000..16e7dd02
--- /dev/null
+++ b/src/test/scala-3/com/earldouglas/sbt/war/TestCompat.scala
@@ -0,0 +1,20 @@
+package com.earldouglas.sbt.war
+
+import java.net.HttpURLConnection
+import java.net.URI
+import scala.jdk.CollectionConverters._
+import scala.io.Source
+import java.util.{List => JavaList}
+import java.util.{Map => JavaMap}
+
+object TestCompat:
+
+  def asScala[A, B](javaMap: JavaMap[A, B]): Map[A, B] =
+    javaMap
+      .asScala
+      .toMap
+
+  def asScala[A](javaList: JavaList[A]): List[A] =
+    javaList
+      .asScala
+      .toList
diff --git a/src/test/scala/com/earldouglas/sbt/war/HttpClient.scala b/src/test/scala/com/earldouglas/sbt/war/HttpClient.scala
index df16941a..adb607d7 100644
--- a/src/test/scala/com/earldouglas/sbt/war/HttpClient.scala
+++ b/src/test/scala/com/earldouglas/sbt/war/HttpClient.scala
@@ -2,7 +2,6 @@ package com.earldouglas.sbt.war
 
 import java.net.HttpURLConnection
 import java.net.URI
-import scala.collection.JavaConverters._
 import scala.io.Source
 
 object HttpClient {
@@ -42,11 +41,15 @@ object HttpClient {
     val response =
       Response(
         status = c.getResponseCode(),
-        headers = c
-          .getHeaderFields()
-          .asScala
+        headers = TestCompat
+          .asScala(
+            c
+              .getHeaderFields()
+          )
           .filter({ case (k, _) => k != null })
-          .map({ case (k, v) => (k, v.asScala.mkString(",")) })
+          .map({ case (k, v) =>
+            (k, TestCompat.asScala(v).mkString(","))
+          })
           .toMap - "Date" - "Content-Length" - "Server",
         body = Source.fromInputStream {
           if (c.getResponseCode() < 400) {
diff --git a/src/test/scala/com/earldouglas/sbt/war/WebappComponentsTest.scala b/src/test/scala/com/earldouglas/sbt/war/WebappComponentsTest.scala
index b7fcdd32..27c51ba2 100644
--- a/src/test/scala/com/earldouglas/sbt/war/WebappComponentsTest.scala
+++ b/src/test/scala/com/earldouglas/sbt/war/WebappComponentsTest.scala
@@ -7,6 +7,8 @@ import java.io.File
 
 class WebappComponentsTest extends AnyFunSuite with Matchers {
 
+  println("asdf")
+
   val fakeproject: File =
     new File("src/test/fakeproject/src/main/webapp")
 
@@ -19,6 +21,8 @@ class WebappComponentsTest extends AnyFunSuite with Matchers {
 
   test("getResources") {
 
+    println("getResources start")
+
     val expected: Map[String, File] =
       Map(
         "bar.html" -> "src/test/fakeproject/src/main/webapp/bar.html",
@@ -30,6 +34,8 @@ class WebappComponentsTest extends AnyFunSuite with Matchers {
       WebappComponents.getResources(fakeproject)
 
     obtained shouldBe expected
+
+    println("getResources end")
   }
 
   test("getClasses") {