diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index fcd76fc..190522b 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -23,7 +23,7 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest, macos-latest]
-        scala: [2.12.20]
+        scala: [2.12.20, 3.7.3]
         java: [temurin@8, temurin@11, temurin@17, temurin@21]
         exclude:
           - java: temurin@8
@@ -79,7 +79,7 @@ jobs:
       - name: Check that workflows are up to date
         run: sbt '++ ${{ matrix.scala }}' githubWorkflowCheck
 
-      - run: sbt '++ ${{ matrix.scala }}' test scripted
+      - run: sbt '++ ${{ matrix.scala }}' test runScriptedTests
 
       - name: Compress target directories
         run: tar cf targets.tar target project/target
@@ -151,6 +151,16 @@ jobs:
           tar xf targets.tar
           rm targets.tar
 
+      - name: Download target directories (3.7.3)
+        uses: actions/download-artifact@v4
+        with:
+          name: target-${{ matrix.os }}-3.7.3-${{ matrix.java }}
+
+      - name: Inflate target directories (3.7.3)
+        run: |
+          tar xf targets.tar
+          rm targets.tar
+
       - name: Publish project
         env:
           PGP_PASSPHRASE: ${{ secrets.PGP_PASSPHRASE }}
diff --git a/build.sbt b/build.sbt
index 000ce99..17a152c 100644
--- a/build.sbt
+++ b/build.sbt
@@ -4,9 +4,31 @@ sbtPlugin := true
 enablePlugins(SbtPlugin)
 
 lazy val scala212 = "2.12.20"
-ThisBuild / crossScalaVersions := Seq(scala212)
+lazy val scala3 = "3.7.3"
+ThisBuild / crossScalaVersions := Seq(scala212, scala3)
 ThisBuild / scalaVersion := scala212
 
+pluginCrossBuild / sbtVersion := {
+  scalaBinaryVersion.value match {
+    case "2.12" =>
+      sbtVersion.value
+    case _ =>
+      "2.0.0-RC6"
+  }
+}
+
+TaskKey[Unit]("runScriptedTests") := Def.taskDyn {
+  scalaBinaryVersion.value match {
+    case "3" =>
+      // TODO enable sbt 2 test
+      Def.task {
+        streams.value.log.warn("skip sbt 2 scripted test")
+      }
+    case _ =>
+      scripted.toTask("")
+  }
+}.value
+
 organization := "com.github.sbt"
 
 homepage := Some(url("https://github.com/sbt/sbt-pull-request-validator"))
@@ -65,7 +87,7 @@ ThisBuild / dynver := {
   sbtdynver.DynVer.getGitDescribeOutput(d).mkVersion(versionFmt, fallbackVersion(d))
 }
 
-ThisBuild / githubWorkflowBuild := Seq(WorkflowStep.Sbt(List("test", "scripted")))
+ThisBuild / githubWorkflowBuild := Seq(WorkflowStep.Sbt(List("test", "runScriptedTests")))
 
 ThisBuild / githubWorkflowTargetTags ++= Seq("v*")
 ThisBuild / githubWorkflowPublishTargetBranches :=
diff --git a/src/main/scala-2/com/github/sbt/pullrequestvalidator/ValidatePullRequestCompat.scala b/src/main/scala-2/com/github/sbt/pullrequestvalidator/ValidatePullRequestCompat.scala
new file mode 100644
index 0000000..64ecdb8
--- /dev/null
+++ b/src/main/scala-2/com/github/sbt/pullrequestvalidator/ValidatePullRequestCompat.scala
@@ -0,0 +1,22 @@
+/*
+ * Sbt Pull Request Validator
+ * Copyright Lightbend and Hewlett Packard Enterprise
+ *
+ * Licensed under Apache License 2.0
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * See the NOTICE file distributed with this work for
+ * additional information regarding copyright ownership.
+ */
+
+package com.github.sbt.pullrequestvalidator
+
+import sbt.Credentials
+import sbt.librarymanagement.ivy.DirectCredentials
+
+private[pullrequestvalidator] object ValidatePullRequestCompat {
+  def credentialsForHost(sc: Seq[Credentials], host: String): Option[DirectCredentials] =
+    sbt.Credentials.forHost(sc, host)
+
+  def testFull = sbt.Keys.test
+}
diff --git a/src/main/scala-3/com/github/sbt/pullrequestvalidator/ValidatePullRequestCompat.scala b/src/main/scala-3/com/github/sbt/pullrequestvalidator/ValidatePullRequestCompat.scala
new file mode 100644
index 0000000..7fbc7d8
--- /dev/null
+++ b/src/main/scala-3/com/github/sbt/pullrequestvalidator/ValidatePullRequestCompat.scala
@@ -0,0 +1,23 @@
+/*
+ * Sbt Pull Request Validator
+ * Copyright Lightbend and Hewlett Packard Enterprise
+ *
+ * Licensed under Apache License 2.0
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * See the NOTICE file distributed with this work for
+ * additional information regarding copyright ownership.
+ */
+
+package com.github.sbt.pullrequestvalidator
+
+import sbt.Credentials
+import sbt.internal.librarymanagement.ivy.IvyCredentials
+import sbt.librarymanagement.Credentials.DirectCredentials
+
+private[pullrequestvalidator] object ValidatePullRequestCompat {
+  def credentialsForHost(sc: Seq[Credentials], host: String): Option[DirectCredentials] =
+    IvyCredentials.forHost(sc, host)
+
+  def testFull = sbt.Keys.testFull
+}
diff --git a/src/main/scala/com/github/sbt/pullrequestvalidator/ValidatePullRequest.scala b/src/main/scala/com/github/sbt/pullrequestvalidator/ValidatePullRequest.scala
index a641516..07754aa 100644
--- a/src/main/scala/com/github/sbt/pullrequestvalidator/ValidatePullRequest.scala
+++ b/src/main/scala/com/github/sbt/pullrequestvalidator/ValidatePullRequest.scala
@@ -76,19 +76,26 @@ object ValidatePullRequest extends AutoPlugin {
     lazy val prValidatorGithubRepository = settingKey[Option[String]](
       "Optional name of the repository where Pull Requests are created. Necessary for explicit 'enforced build all'"
     )
+    @transient
     lazy val prValidatorGithubEnforcedBuildAll =
       taskKey[Boolean]("Checks via GitHub API if comments included the PLS BUILD ALL keyword.")
+    @transient
     lazy val prValidatorTravisNonPrEnforcedBuildAll =
       taskKey[Boolean]("Checks whether this is a non PR build on Travis.")
+    @transient
     lazy val prValidatorEnforcedBuildAll = taskKey[Boolean]("Whether an enforced build all is done.")
 
     // determining touched dirs and projects
+    @transient
     lazy val prValidatorChangedProjects = taskKey[Changes]("List of touched projects in this PR branch")
+    @transient
     lazy val prValidatorProjectBuildTasks =
       taskKey[Seq[TaskKey[?]]]("The tasks that should be run, according to what has changed")
 
     // running validation
+    @transient
     lazy val validatePullRequest = taskKey[Unit]("Validate pull request")
+    @transient
     lazy val validatePullRequestBuildAll = taskKey[Unit]("Validate pull request, building all projects")
   }
 
@@ -161,7 +168,7 @@ object ValidatePullRequest extends AutoPlugin {
       val buildAllMagicPhrase = prValidatorBuildAllKeyword.value
       val githubRepository = prValidatorGithubRepository.value
       val githubEndpoint = prValidatorGithubEndpoint.value
-      val githubCredentials = Credentials.forHost(credentials.value, githubEndpoint.getHost)
+      val githubCredentials = ValidatePullRequestCompat.credentialsForHost(credentials.value, githubEndpoint.getHost)
 
       pullRequestId.exists { prId =>
         log.info("Checking GitHub comments for PR validation options...")
@@ -291,7 +298,7 @@ object ValidatePullRequest extends AutoPlugin {
         Seq()
       }
     },
-    prValidatorTasks := Seq(Test / test),
+    prValidatorTasks := Seq(Test / ValidatePullRequestCompat.testFull),
     prValidatorBuildAllTasks := prValidatorTasks.value,
     prValidatorEnforcedBuildAllTasks := prValidatorBuildAllTasks.value,
     validatePullRequest := Def.taskDyn {