diff --git a/sbt-app/src/sbt-test/actions/call/build.sbt b/sbt-app/src/sbt-test/actions/call/build.sbt
index 8ff9b8f9d..720ea3346 100644
--- a/sbt-app/src/sbt-test/actions/call/build.sbt
+++ b/sbt-app/src/sbt-test/actions/call/build.sbt
@@ -3,7 +3,7 @@ sbtPlugin := true
 val copyOutputDir = taskKey[Unit]("Copies the compiled classes to a root-level directory")
 
 copyOutputDir := {
-	val cd = (classDirectory in Compile).value
+	val cd = (Compile / classDirectory).value
 	val to = baseDirectory.value / "out spaced"
 	IO.copyDirectory(cd, to)
 }
diff --git a/sbt-app/src/sbt-test/actions/clean-managed/build.sbt b/sbt-app/src/sbt-test/actions/clean-managed/build.sbt
index cedf36e1c..1505d55f0 100644
--- a/sbt-app/src/sbt-test/actions/clean-managed/build.sbt
+++ b/sbt-app/src/sbt-test/actions/clean-managed/build.sbt
@@ -1,9 +1,11 @@
 import sbt.nio.file.Glob
 
-Compile / sourceGenerators += Def.task {
-  val files = Seq(sourceManaged.value / "foo.txt", sourceManaged.value / "bar.txt")
-  files.foreach(IO.touch(_))
-  files
+Compile / sourceGenerators += {
+  Def.task {
+    val files = Seq(sourceManaged.value / "foo.txt", sourceManaged.value / "bar.txt")
+    files.foreach(IO.touch(_))
+    files
+  }
 }
 
 cleanKeepGlobs += Glob(sourceManaged.value, "bar.txt")
diff --git a/sbt-app/src/sbt-test/actions/compile-clean/build.sbt b/sbt-app/src/sbt-test/actions/compile-clean/build.sbt
index 0b40a6eb6..d76c2ffb2 100644
--- a/sbt-app/src/sbt-test/actions/compile-clean/build.sbt
+++ b/sbt-app/src/sbt-test/actions/compile-clean/build.sbt
@@ -1,4 +1,4 @@
 import sbt.nio.file.Glob
 
-cleanKeepGlobs in Compile +=
-  Glob((classDirectory in Compile in compile).value, "X.class")
+Compile / cleanKeepGlobs +=
+  Glob((Compile / compile / classDirectory).value, "X.class")
diff --git a/sbt-app/src/sbt-test/actions/compile-time-only/build.sbt b/sbt-app/src/sbt-test/actions/compile-time-only/build.sbt
index f8d308a29..108396ca6 100644
--- a/sbt-app/src/sbt-test/actions/compile-time-only/build.sbt
+++ b/sbt-app/src/sbt-test/actions/compile-time-only/build.sbt
@@ -6,9 +6,8 @@ libraryDependencies += "org.scala-sbt" % "sbt" % sbtVersion.value
 lazy val expectErrorNotCrash = taskKey[Unit]("Ensures that sbt properly set types on Trees so that the compiler doesn't crash on a bad reference to .value, but gives a proper error instead.")
 
 expectErrorNotCrash := {
-        val fail = (compileIncremental in Compile).failure.value
-	fail.directCause match {
-		case Some(x: xsbti.CompileFailed) => ()
-		case _ => sys.error("Compiler crashed instead of providing a compile-time-only exception.")
-	}
+  val fail = (Compile / compileIncremental).failure.value
+  fail.directCause match
+    case Some(x: xsbti.CompileFailed) => ()
+    case _ => sys.error("Compiler crashed instead of providing a compile-time-only exception.")
 }
diff --git a/sbt-app/src/sbt-test/actions/compile/test b/sbt-app/src/sbt-test/actions/compile/test
index 0c25100b6..9978a9516 100644
--- a/sbt-app/src/sbt-test/actions/compile/test
+++ b/sbt-app/src/sbt-test/actions/compile/test
@@ -1,5 +1,5 @@
 -> compile
 
-> 'set sources in (Compile, compile) := { val src = (sources in (Compile, compile)).value; src.filterNot(_.getName contains "C") }'
+> 'set Compile / compile / sources := { val src = (Compile / compile / sources).value; src.filterNot(_.getName contains "C") }'
 
 > compile
diff --git a/sbt-app/src/sbt-test/actions/configuration-delegation/build.sbt b/sbt-app/src/sbt-test/actions/configuration-delegation/build.sbt
index 029644912..bc45e0058 100644
--- a/sbt-app/src/sbt-test/actions/configuration-delegation/build.sbt
+++ b/sbt-app/src/sbt-test/actions/configuration-delegation/build.sbt
@@ -3,15 +3,13 @@ lazy val foo = taskKey[Unit]("Runs the foo task")
 lazy val bar = taskKey[Unit]("Runs the bar task")
 
 def makeFoo(config: Configuration): Setting[_] = 
-  foo in config := IO.write(file(s"${config.name}-foo"), "foo")
+  config / foo := IO.write(file(s"${config.name}-foo"), "foo")
 
 lazy val PerformanceTest = (config("pt") extend Test)
 
-lazy val root = (
-  (project in file("."))
+lazy val root = (project in file("."))
   .configs(PerformanceTest)
   .settings(Seq(Compile, Test, Runtime, PerformanceTest).map(makeFoo) :_*)
   .settings(
-     bar in PerformanceTest := IO.write(file("pt-bar"), "bar")
+     PerformanceTest / bar := IO.write(file("pt-bar"), "bar")
   )
-)
\ No newline at end of file
diff --git a/sbt-app/src/sbt-test/actions/doc/build.sbt b/sbt-app/src/sbt-test/actions/doc/build.sbt
index 8f1b96ff9..7036a6f1e 100644
--- a/sbt-app/src/sbt-test/actions/doc/build.sbt
+++ b/sbt-app/src/sbt-test/actions/doc/build.sbt
@@ -9,11 +9,11 @@ lazy val root = (project in file("."))
     scalaVersion := "2.12.12",
     Compile / doc / scalacOptions += "-Xfatal-warnings",
     commands += Command.command("excludeB") { s =>
-      val impl = """val src = (sources in Compile).value; src.filterNot(_.getName.contains("B"))"""
-      s"set sources in (Compile, doc) := { $impl }" :: s
+      val impl = """val src = (Compile / sources).value; src.filterNot(_.getName.contains("B"))"""
+      s"set Compile / doc / sources := { $impl }" :: s
     },
     commands += Command.arb(_ => ("setDocExtension": Parser[String]) ~> " " ~> matched(any.*)) { (s, filter: String) =>
-      val impl = s"""val src = (sources in Compile).value; src.filter(_.getName.endsWith("$filter"))"""
-      s"set sources in (Compile, doc) := { $impl }" :: s
+      val impl = s"""val src = (Compile / sources).value; src.filter(_.getName.endsWith("$filter"))"""
+      s"set Compile / doc / sources := { $impl }" :: s
     },
   )
diff --git a/sbt-app/src/sbt-test/actions/eval-is-safe-and-sound/build.sbt b/sbt-app/src/sbt-test/actions/eval-is-safe-and-sound/build.sbt
index 12bedf524..5e339bf95 100644
--- a/sbt-app/src/sbt-test/actions/eval-is-safe-and-sound/build.sbt
+++ b/sbt-app/src/sbt-test/actions/eval-is-safe-and-sound/build.sbt
@@ -18,7 +18,7 @@ lazy val checkDifferentConfigClasses = taskKey[Unit]("Checks that the number of
 configClassCountFile := (target.value / "config-count")
 
 numConfigClasses := {
-  val cdir = (baseDirectory in ThisBuild).value / "project/target/config-classes"
+  val cdir = (ThisBuild / baseDirectory).value / "project/target/config-classes"
   (cdir.allPaths --- cdir).get.length
 }
 
diff --git a/sbt-app/src/sbt-test/actions/external-doc/build.sbt b/sbt-app/src/sbt-test/actions/external-doc/build.sbt
index fe2d502d8..23cc3290f 100644
--- a/sbt-app/src/sbt-test/actions/external-doc/build.sbt
+++ b/sbt-app/src/sbt-test/actions/external-doc/build.sbt
@@ -2,31 +2,31 @@
 ThisBuild / useCoursier := false
 
 Seq(
-	autoAPIMappings in ThisBuild := true,
-	publishArtifact in (ThisBuild, packageDoc) := false,
-	publishArtifact in packageSrc := false,
-	organization in ThisBuild := "org.example",
-	version := "1.0"
+  ThisBuild / autoAPIMappings := true,
+  ThisBuild / packageDoc / publishArtifact := false,
+  packageSrc / publishArtifact := false,
+  ThisBuild / organization := "org.example",
+  version := "1.0",
 )
 
 val aPublishResolver = Def.setting {
-	Resolver.file("a-resolver", baseDirectory.in(ThisBuild).value / "a-repo")
+  Resolver.file("a-resolver", (ThisBuild / baseDirectory).value / "a-repo")
 }
 val aResolver = Def.setting {
-	val dir = baseDirectory.in(ThisBuild).value
-	"a-resolver" at s"file://${dir.getAbsolutePath}/a-repo"
+  val dir = (ThisBuild / baseDirectory).value
+  "a-resolver" at s"file://${dir.getAbsolutePath}/a-repo"
 }
 
 val bResolver = Def.setting {
-	val dir = baseDirectory.in(ThisBuild).value / "b-repo"
-	Resolver.file("b-resolver", dir)(Resolver.defaultIvyPatterns)
+  val dir = (ThisBuild / baseDirectory).value / "b-repo"
+  Resolver.file("b-resolver", dir)(Resolver.defaultIvyPatterns)
 }
 
 val apiBaseSetting = apiURL := Some(apiBase(name.value))
 def apiBase(projectName: String) = url(s"http://example.org/${projectName}")
 def scalaLibraryBase(v: String) = url(s"https://www.scala-lang.org/api/$v/")
 def addDep(projectName: String) =
-	libraryDependencies += organization.value %% projectName % version.value
+  libraryDependencies += organization.value %% projectName % version.value
 
 
 val checkApiMappings = taskKey[Unit]("Verifies that the API mappings are collected as expected.")
@@ -34,44 +34,44 @@ val checkApiMappings = taskKey[Unit]("Verifies that the API mappings are collect
 def expectedMappings = Def.task {
   val version = scalaVersion.value
   val binVersion = scalaBinaryVersion.value
-	val ms = update.value.configuration(Compile).get.modules.flatMap { mod => 
-		mod.artifacts.flatMap { case (a,f) =>
-			val n = a.name.stripSuffix("_" + binVersion)
-			n match {
-				case "a" | "b" | "c" => (f, apiBase(n)) :: Nil
-				case "scala-library" => (f, scalaLibraryBase(version)) :: Nil
-				case _ => Nil
-			}
-		}
-	}
-	val mc = (classDirectory in (c,Compile)).value -> apiBase("c")
-	(mc +: ms).toMap
+  val ms = update.value.configuration(Compile).get.modules.flatMap { mod =>
+    mod.artifacts.flatMap { case (a,f) =>
+      val n = a.name.stripSuffix("_" + binVersion)
+      n match {
+        case "a" | "b" | "c" => (f, apiBase(n)) :: Nil
+        case "scala-library" => (f, scalaLibraryBase(version)) :: Nil
+        case _ => Nil
+      }
+    }
+  }
+  val mc = (Compile / c / classDirectory).value -> apiBase("c")
+  (mc +: ms).toMap
 }
 
 
 val a = project.settings(
-	apiBaseSetting,
-	publishMavenStyle := true,
-	publishTo := Some(aPublishResolver.value)
+  apiBaseSetting,
+  publishMavenStyle := true,
+  publishTo := Some(aPublishResolver.value)
 )
 
 val b = project.settings(
-	apiBaseSetting,
-	publishMavenStyle := false,
-	publishTo := Some(bResolver.value)
+  apiBaseSetting,
+  publishMavenStyle := false,
+  publishTo := Some(bResolver.value)
 )
 
 val c = project.settings(apiBaseSetting)
 
 val d = project.dependsOn( c ).settings(
-	externalResolvers := Seq(aResolver.value, bResolver.value),
-	addDep("a"),
-	addDep("b"),
-	checkApiMappings := {
-		val actual = apiMappings.in(Compile,doc).value
-		println("Actual API Mappings: " + actual.mkString("\n\t", "\n\t", ""))
-		val expected = expectedMappings.value
-		println("Expected API Mappings: " + expected.mkString("\n\t", "\n\t", ""))
-		assert(actual == expected)
-	}
+  externalResolvers := Seq(aResolver.value, bResolver.value),
+  addDep("a"),
+  addDep("b"),
+  checkApiMappings := {
+    val actual = (Compile / doc / apiMappings).value
+    println("Actual API Mappings: " + actual.mkString("\n\t", "\n\t", ""))
+    val expected = expectedMappings.value
+    println("Expected API Mappings: " + expected.mkString("\n\t", "\n\t", ""))
+    assert(actual == expected)
+  }
 )
diff --git a/sbt-app/src/sbt-test/actions/generator/build.sbt b/sbt-app/src/sbt-test/actions/generator/build.sbt
index d9139f3a0..56dbe41e1 100644
--- a/sbt-app/src/sbt-test/actions/generator/build.sbt
+++ b/sbt-app/src/sbt-test/actions/generator/build.sbt
@@ -9,6 +9,6 @@ lazy val root = (project in file("."))
       IO.write(file, "object BuildInfo")
       file :: Nil
     },
-    sourceGenerators in Compile += buildInfo,
-    sourceGenerators in Compile += Def.task { Nil }
+    Compile / sourceGenerators += buildInfo,
+    Compile / sourceGenerators += Def.task { Nil },
   )
diff --git a/sbt-app/src/sbt-test/actions/input-task-dyn/build.sbt b/sbt-app/src/sbt-test/actions/input-task-dyn/build.sbt
index 46d9578d5..d87e3f2d0 100644
--- a/sbt-app/src/sbt-test/actions/input-task-dyn/build.sbt
+++ b/sbt-app/src/sbt-test/actions/input-task-dyn/build.sbt
@@ -10,7 +10,7 @@ lazy val root = (project in file(".")).
     name := "run-test",
     runFoo := Def.inputTaskDyn {
         val args = Def.spaceDelimited().parsed
-        (runMain in Compile).toTask(s" Foo " + args.mkString(" "))
+        (Compile / runMain).toTask(s" Foo " + args.mkString(" "))
     }.evaluated,
     check := {
       val x = runFoo.toTask(" hi ho").value
diff --git a/sbt-app/src/sbt-test/actions/input-task/build.sbt b/sbt-app/src/sbt-test/actions/input-task/build.sbt
index 3d61bdf90..f19e32f7b 100644
--- a/sbt-app/src/sbt-test/actions/input-task/build.sbt
+++ b/sbt-app/src/sbt-test/actions/input-task/build.sbt
@@ -12,9 +12,9 @@ lazy val root = (project in file(".")).
   settings(
     name := "run-test",
     run2 := {
-       val one = (run in Compile).evaluated
+       val one = (Compile / run).evaluated
        val sep = separator.parsed
-       val two = (run in Compile).evaluated
+       val two = (Compile / run).evaluated
     },
     check := {
       val x = run2.toTask(" a b -- c d").value
diff --git a/sbt-app/src/sbt-test/actions/join/build.sbt b/sbt-app/src/sbt-test/actions/join/build.sbt
index ac73e48c3..bef19f465 100644
--- a/sbt-app/src/sbt-test/actions/join/build.sbt
+++ b/sbt-app/src/sbt-test/actions/join/build.sbt
@@ -3,18 +3,18 @@ lazy val intTask = taskKey[Int]("int")
 lazy val root = (project in file(".")).
   dependsOn(b, c).
   settings(
-    intTask in Compile := {
+    Compile / intTask := {
       // a sequence of tasks could be joined together
-      Seq(b, c).map(p => intTask in (p, Compile)).join.map( as => (1 /: as)(_ + _) ).value
+      Seq(b, c).map(p => Cmpile / p / intTask).join.map( as => (1 /: as)(_ + _) ).value
     }
   )
 
 lazy val b = (project in file("b")).
   settings(
-    intTask in Compile := 1
+    Compile / intTask := 1
   )
 
 lazy val c = (project in file("c")).
   settings{
-    intTask in Compile := 2
+    Compile / intTask := 2
   }
diff --git a/sbt-app/src/sbt-test/actions/multi-scope/build.sbt b/sbt-app/src/sbt-test/actions/multi-scope/build.sbt
index 654c75d38..fd5bc2492 100644
--- a/sbt-app/src/sbt-test/actions/multi-scope/build.sbt
+++ b/sbt-app/src/sbt-test/actions/multi-scope/build.sbt
@@ -59,15 +59,15 @@ lazy val b = project
 
 lazy val c = project.settings(
 	taskX := cGlobal,
-	taskX in Compile := cCompile,
-	taskX in Test := cTest
+	Compile / taskX := cCompile,
+	Test / taskX := cTest
 )
 
 lazy val d = project.settings(
 	taskX := dGlobal,
-	taskX in (Compile,console) := dConsole,
+	Compile / console / taskX := dConsole,
 	// these shouldn't get picked up
-	taskX in (Compile,compile) := Set(32366),
-	taskX in compile := Set(548686),
-	taskX in Configurations.IntegrationTest := Set(11111)
-)
\ No newline at end of file
+	Compile / compile / taskX := Set(32366),
+	compile / taskX := Set(548686),
+	Configurations.IntegrationTest / taskX := Set(11111),
+)
diff --git a/sbt-app/src/sbt-test/actions/previous/scopes.sbt b/sbt-app/src/sbt-test/actions/previous/scopes.sbt
index 8062b1df1..16af91fad 100644
--- a/sbt-app/src/sbt-test/actions/previous/scopes.sbt
+++ b/sbt-app/src/sbt-test/actions/previous/scopes.sbt
@@ -9,39 +9,38 @@ lazy val subB = project
 
 x := 3
 
-x in Compile in y := 7
+Compile / y / x := 7
 
-x in Runtime in y := 13
+Runtime / y / x := 13
 
-x in subA in Compile := {
-	val xcy = (x in Compile in y).previous getOrElse 0  // 7
-	// verify that This is properly resolved to Global and not the defining key's scope
-	val xg = x.previous getOrElse 0  // 3
-	println(s"xcy=$xcy, xg=$xg")
-	xcy * xg
+subA / Compile / x := {
+  val xcy = (Compile / y / x).previous getOrElse 0  // 7
+  // verify that This is properly resolved to Global and not the defining key's scope
+  val xg = x.previous getOrElse 0  // 3
+  println(s"xcy=$xcy, xg=$xg")
+  xcy * xg
 }
 
-
 inConfig(Compile)(Seq(
-	y in subB := {
-		// verify that the referenced key gets delegated
-		val xty = (x in Test in y).previous getOrElse 0  // 13
-		// verify that inConfig gets applied
-		val xcy = (x in y).previous getOrElse 0  // 7
-		println(s"xcy=$xcy, xty=$xty")
-		xty * xcy
-	}
+  subB / y := {
+    // verify that the referenced key gets delegated
+    val xty = (Test / y / x).previous getOrElse 0  // 13
+    // verify that inConfig gets applied
+    val xcy = (y / x).previous getOrElse 0  // 7
+    println(s"xcy=$xcy, xty=$xty")
+    xty * xcy
+  }
 ))
 
 def parser = {
-	import complete.DefaultParsers._
-	(Space ~> IntBasic) ~ (Space ~> IntBasic)
+  import complete.DefaultParsers._
+  (Space ~> IntBasic) ~ (Space ~> IntBasic)
 }
 
 checkScopes := {
-	val (expectedX, expectedY) = parser.parsed
-	val actualX = (x in subA in Compile).value
-	val actualY = (y in subB in Test).value
-	assert(actualX == expectedX, s"Expected 'x' to be $expectedX, got $actualX")
-	assert(actualY == expectedY, s"Expected 'y' to be $expectedY, got $actualY")
+  val (expectedX, expectedY) = parser.parsed
+  val actualX = (subA/ Compile / x).value
+  val actualY = (subB / Test / y).value
+  assert(actualX == expectedX, s"Expected 'x' to be $expectedX, got $actualX")
+  assert(actualY == expectedY, s"Expected 'y' to be $expectedY, got $actualY")
 }
diff --git a/sbt-app/src/sbt-test/actions/remote-cache/build.sbt b/sbt-app/src/sbt-test/actions/remote-cache/build.sbt
index 920bc2e0c..43766a055 100644
--- a/sbt-app/src/sbt-test/actions/remote-cache/build.sbt
+++ b/sbt-app/src/sbt-test/actions/remote-cache/build.sbt
@@ -42,7 +42,7 @@ lazy val root = (project in file("."))
     recordPreviousIterations := {
       val log = streams.value.log
       CompileState.previousIterations = {
-        val previousAnalysis = (previousCompile in Compile).value.analysis.asScala
+        val previousAnalysis = (Compile / previousCompile).value.analysis.asScala
         previousAnalysis match {
           case None =>
             log.info("No previous analysis detected")
@@ -53,7 +53,7 @@ lazy val root = (project in file("."))
     },
     checkIterations := {
       val expected: Int = (Space ~> NatBasic).parsed
-      val actual: Int = ((compile in Compile).value match { case a: Analysis => a.compilations.allCompilations.size }) - CompileState.previousIterations
+      val actual: Int = ((Compile / compile).value match { case a: Analysis => a.compilations.allCompilations.size }) - CompileState.previousIterations
       assert(expected == actual, s"Expected $expected compilations, got $actual")
     }
   )
diff --git a/sbt-app/src/sbt-test/actions/run-task/build.sbt b/sbt-app/src/sbt-test/actions/run-task/build.sbt
index 69fb3e613..4f0a4ed3a 100644
--- a/sbt-app/src/sbt-test/actions/run-task/build.sbt
+++ b/sbt-app/src/sbt-test/actions/run-task/build.sbt
@@ -1,7 +1,7 @@
 val demo = taskKey[Unit]("Demo run task")
 fullRunTask(demo, Compile, "A", "1", "1")
-fork in demo := true
-javaOptions in demo := "-Dsbt.check.forked=true" :: Nil
+demo / fork := true
+demo / javaOptions := "-Dsbt.check.forked=true" :: Nil
 
 val demoIn = InputKey[Unit]("demoIn", "Demo run input task", demo)
 fullRunInputTask(demoIn, Compile, "A", "1")
diff --git a/sbt-app/src/sbt-test/apiinfo/extracted/build.sbt b/sbt-app/src/sbt-test/apiinfo/extracted/build.sbt
index 37533b32a..eab867380 100644
--- a/sbt-app/src/sbt-test/apiinfo/extracted/build.sbt
+++ b/sbt-app/src/sbt-test/apiinfo/extracted/build.sbt
@@ -44,11 +44,11 @@ def testInputTask[T](name: String, expected: String, task: InputKey[T], arg: Str
 myInputTask := argFunction(_.toUpperCase(Locale.ENGLISH)).evaluated
 testInputTask("testRunInputTaskRoot", "FOO", myInputTask, "foo")
 
-myInputTask in Compile := argFunction(_.toLowerCase(Locale.ENGLISH)).evaluated
+Compile / myInputTask := argFunction(_.toLowerCase(Locale.ENGLISH)).evaluated
 testInputTask("testRunInputTaskRootCompile", "foo", myInputTask in Compile, "FOO")
 
-myInputTask in sub := argFunction(_.head.toString).evaluated
+sub / myInputTask := argFunction(_.head.toString).evaluated
 testInputTask("testRunInputTaskSub", "f", myInputTask in sub, "foo")
 
-myInputTask in (sub, Compile) := argFunction(_.tail).evaluated
+sub / Compile / myInputTask := argFunction(_.tail).evaluated
 testInputTask("testRunInputTaskSubCompile", "oo", myInputTask in (sub, Compile), "foo")
diff --git a/sbt-app/src/sbt-test/apiinfo/show-circular-structure/build.sbt b/sbt-app/src/sbt-test/apiinfo/show-circular-structure/build.sbt
index 6d28ec8e9..21146aa3d 100644
--- a/sbt-app/src/sbt-test/apiinfo/show-circular-structure/build.sbt
+++ b/sbt-app/src/sbt-test/apiinfo/show-circular-structure/build.sbt
@@ -5,9 +5,9 @@ logLevel := Level.Debug
 incOptions ~= { _.withApiDebug(true) }
 
 TaskKey[Unit]("show-apis") := {
-  val a = (compile in Compile).value match { case a: Analysis => a }
-  val scalaSrc = (scalaSource in Compile).value
-  val javaSrc = (javaSource in Compile).value
+  val a = (Compile / compile).value match { case a: Analysis => a }
+  val scalaSrc = (Compile / scalaSource).value
+  val javaSrc = (Compile / javaSource).value
   val aApi = a.apis.internalAPI("test.A").api.classApi
   val jApi = a.apis.internalAPI("test.J").api.classApi
   import xsbt.api.DefaultShowAPI
diff --git a/sbt-app/src/sbt-test/apiinfo/unstable-existential-names/build.sbt b/sbt-app/src/sbt-test/apiinfo/unstable-existential-names/build.sbt
index 1036709cc..3888dda98 100644
--- a/sbt-app/src/sbt-test/apiinfo/unstable-existential-names/build.sbt
+++ b/sbt-app/src/sbt-test/apiinfo/unstable-existential-names/build.sbt
@@ -6,7 +6,7 @@ val recordPreviousIterations = taskKey[Unit]("Record previous iterations.")
 recordPreviousIterations := {
   val log = streams.value.log
   CompileState.previousIterations = {
-    val previousAnalysis = (previousCompile in Compile).value.analysis.asScala
+    val previousAnalysis = (Compile / previousCompile).value.analysis.asScala
     previousAnalysis match {
       case None =>
         log.info("No previous analysis detected")
@@ -20,6 +20,6 @@ val checkIterations = inputKey[Unit]("Verifies the accumulated number of iterati
 
 checkIterations := {
   val expected: Int = (Space ~> NatBasic).parsed
-  val actual: Int = ((compile in Compile).value match { case a: Analysis => a.compilations.allCompilations.size }) - CompileState.previousIterations
+  val actual: Int = ((Compile / compile).value match { case a: Analysis => a.compilations.allCompilations.size }) - CompileState.previousIterations
   assert(expected == actual, s"Expected $expected compilations, got $actual")
 }
diff --git a/sbt-app/src/sbt-test/compiler-project/inc-package-class-dependency/build.sbt b/sbt-app/src/sbt-test/compiler-project/inc-package-class-dependency/build.sbt
index a9b970121..ce36e14da 100644
--- a/sbt-app/src/sbt-test/compiler-project/inc-package-class-dependency/build.sbt
+++ b/sbt-app/src/sbt-test/compiler-project/inc-package-class-dependency/build.sbt
@@ -1,8 +1,8 @@
 import sbt.internal.inc.Analysis
 
 TaskKey[Unit]("verify-binary-deps") := {
-  val a = (compile in Compile).value match { case a: Analysis => a }
-  val classDir = (classDirectory in Compile).value
+  val a = (Compile / compile).value match { case a: Analysis => a }
+  val classDir = (Compile / classDirectory).value
   val base = baseDirectory.value
   val nestedPkgClass = classDir / "test/nested.class"
   val fooSrc = base / "src/main/scala/test/nested/Foo.scala"
diff --git a/sbt-app/src/sbt-test/compiler-project/inc-pickled-existential/build.sbt b/sbt-app/src/sbt-test/compiler-project/inc-pickled-existential/build.sbt
index 1284c994c..aa808c75e 100644
--- a/sbt-app/src/sbt-test/compiler-project/inc-pickled-existential/build.sbt
+++ b/sbt-app/src/sbt-test/compiler-project/inc-pickled-existential/build.sbt
@@ -8,7 +8,7 @@ val recordPreviousIterations = taskKey[Unit]("Record previous iterations.")
 recordPreviousIterations := {
   val log = streams.value.log
   CompileState.previousIterations = {
-    val previousAnalysis = (previousCompile in Compile).value.analysis.asScala
+    val previousAnalysis = (Compile / previousCompile).value.analysis.asScala
     previousAnalysis match {
       case None =>
         log.info("No previous analysis detected")
@@ -22,6 +22,6 @@ val checkIterations = inputKey[Unit]("Verifies the accumulated number of iterati
 
 checkIterations := {
   val expected: Int = (Space ~> NatBasic).parsed
-  val actual: Int = ((compile in Compile).value match { case a: Analysis => a.compilations.allCompilations.size }) - CompileState.previousIterations
+  val actual: Int = ((Compile / compile).value match { case a: Analysis => a.compilations.allCompilations.size }) - CompileState.previousIterations
   assert(expected == actual, s"Expected $expected compilations, got $actual")
 }
diff --git a/sbt-app/src/sbt-test/compiler-project/inc-pickled-refinement/build.sbt b/sbt-app/src/sbt-test/compiler-project/inc-pickled-refinement/build.sbt
index 1036709cc..b27b7f236 100644
--- a/sbt-app/src/sbt-test/compiler-project/inc-pickled-refinement/build.sbt
+++ b/sbt-app/src/sbt-test/compiler-project/inc-pickled-refinement/build.sbt
@@ -6,7 +6,7 @@ val recordPreviousIterations = taskKey[Unit]("Record previous iterations.")
 recordPreviousIterations := {
   val log = streams.value.log
   CompileState.previousIterations = {
-    val previousAnalysis = (previousCompile in Compile).value.analysis.asScala
+    val previousAnalysis = (Compile  / previousCompile).value.analysis.asScala
     previousAnalysis match {
       case None =>
         log.info("No previous analysis detected")
@@ -20,6 +20,6 @@ val checkIterations = inputKey[Unit]("Verifies the accumulated number of iterati
 
 checkIterations := {
   val expected: Int = (Space ~> NatBasic).parsed
-  val actual: Int = ((compile in Compile).value match { case a: Analysis => a.compilations.allCompilations.size }) - CompileState.previousIterations
+  val actual: Int = ((Compile / compile).value match { case a: Analysis => a.compilations.allCompilations.size }) - CompileState.previousIterations
   assert(expected == actual, s"Expected $expected compilations, got $actual")
 }
diff --git a/sbt-app/src/sbt-test/compiler-project/macro-config/build.sbt b/sbt-app/src/sbt-test/compiler-project/macro-config/build.sbt
index 248b7cb45..15598d96a 100644
--- a/sbt-app/src/sbt-test/compiler-project/macro-config/build.sbt
+++ b/sbt-app/src/sbt-test/compiler-project/macro-config/build.sbt
@@ -19,15 +19,15 @@ lazy val root = (project in file("."))
     inConfig(Macro)(Defaults.configSettings),
 
     // puts the compiled macro on the classpath for the main sources
-    unmanagedClasspath in Compile ++=
-      (fullClasspath in Macro).value,
+    Compile / unmanagedClasspath ++=
+      (Macro / fullClasspath).value,
 
     // includes sources in src/macro/ in the main source package
-    mappings in (Compile, packageSrc) ++=
-      (mappings in (Macro, packageSrc)).value,
+    Compile / packageSrc / mappings ++=
+      (Macro / packageSrc / mappings).value,
 
     // Includes classes compiled from src/macro/ in the main binary
     // This can be omitted if the classes in src/macro/ aren't used at runtime
-    mappings in (Compile, packageBin) ++=
-      (mappings in (Macro, packageBin)).value
+    Compile / packageBin / mappings ++=
+      (Macro / packageBin / mappings).value
   )
diff --git a/sbt-app/src/sbt-test/compiler-project/semantic-errors/build.sbt b/sbt-app/src/sbt-test/compiler-project/semantic-errors/build.sbt
index 019d06f89..913667f36 100644
--- a/sbt-app/src/sbt-test/compiler-project/semantic-errors/build.sbt
+++ b/sbt-app/src/sbt-test/compiler-project/semantic-errors/build.sbt
@@ -1,6 +1,6 @@
 TaskKey[Unit]("checkJavaFailures") := {
   val reporter = savedReporter.value
-  val ignore = (compile in Compile).failure.value
+  val ignore = (Compile / compile).failure.value
   val ps = reporter.problems
   assert(!ps.isEmpty, "Failed to report any problems!")
   // First error should be on a specific line/file
@@ -13,7 +13,7 @@ TaskKey[Unit]("checkJavaFailures") := {
 
 TaskKey[Unit]("checkScalaFailures") := {
   val reporter = savedReporter.value
-  val ignore = (compile in Compile).failure.value
+  val ignore = (Compile / compile).failure.value
   val ps = reporter.problems
   assert(!ps.isEmpty, "Failed to report any problems!")
   // First error should be on a specific line/file
diff --git a/sbt-app/src/sbt-test/compiler-project/semantic-errors/project/src/main/scala/sbt/TestPlugin.scala b/sbt-app/src/sbt-test/compiler-project/semantic-errors/project/src/main/scala/sbt/TestPlugin.scala
index d8c5e0c59..165405526 100644
--- a/sbt-app/src/sbt-test/compiler-project/semantic-errors/project/src/main/scala/sbt/TestPlugin.scala
+++ b/sbt-app/src/sbt-test/compiler-project/semantic-errors/project/src/main/scala/sbt/TestPlugin.scala
@@ -14,7 +14,7 @@ object TestPlugin extends AutoPlugin {
   import autoImport._
   override def projectSettings = Seq(
     savedReporter := new CollectingReporter,
-    compilerReporter in (Compile, compile) := savedReporter.value,
+    Compile / compile / compilerReporter := savedReporter.value,
     problems := savedReporter.value.problems
   )
 }
diff --git a/sbt-app/src/sbt-test/compiler-project/separate-analysis-per-scala/build.sbt b/sbt-app/src/sbt-test/compiler-project/separate-analysis-per-scala/build.sbt
index 804a1206d..77191747f 100644
--- a/sbt-app/src/sbt-test/compiler-project/separate-analysis-per-scala/build.sbt
+++ b/sbt-app/src/sbt-test/compiler-project/separate-analysis-per-scala/build.sbt
@@ -9,7 +9,7 @@ lazy val root = (project in file("."))
     incOptions := incOptions.value.withClassfileManagerType(
       Option(xsbti.compile.TransactionalManagerType.of(
         crossTarget.value / "classes.bak",
-        (streams in (Compile, compile)).value.log
+        (Compile / compile / streams).value.log
       ): xsbti.compile.ClassFileManagerType).asJava
     )
   )
diff --git a/sbt-app/src/sbt-test/package/manifest/build.sbt b/sbt-app/src/sbt-test/package/manifest/build.sbt
index 73ac1427d..2711329b8 100644
--- a/sbt-app/src/sbt-test/package/manifest/build.sbt
+++ b/sbt-app/src/sbt-test/package/manifest/build.sbt
@@ -9,11 +9,11 @@ crossPaths := false
 
 mainClass := Some("jartest.Main")
 
-packageOptions in (Compile, packageBin) := {
+Compile / packageBin / packageOptions := {
   def manifestExtra = {
     val mf = new Manifest
     mf.getMainAttributes.put(Attributes.Name.CLASS_PATH, makeString(scalaInstance.value.libraryJars))
     mf
   }
-  (packageOptions in (Compile, packageBin)).value :+ Package.JarManifest(manifestExtra)
+  (Compile / packageBin / packageOptions).value :+ Package.JarManifest(manifestExtra)
 }
diff --git a/sbt-app/src/sbt-test/package/mappings/build.sbt b/sbt-app/src/sbt-test/package/mappings/build.sbt
index dc930b4ae..81c727e70 100644
--- a/sbt-app/src/sbt-test/package/mappings/build.sbt
+++ b/sbt-app/src/sbt-test/package/mappings/build.sbt
@@ -2,7 +2,7 @@ name := "Mappings Test"
 
 version := "0.2"
 
-mappings in (Compile, packageBin) ++= {
+Compile / packageBin / mappings ++= {
   val test = file("test")
   Seq(
     test -> "test1",
@@ -13,5 +13,5 @@ mappings in (Compile, packageBin) ++= {
 
 lazy val unzipPackage = taskKey[Unit]("extract jar file")
 unzipPackage := {
-  IO.unzip((packageBin in Compile).value, target.value / "extracted")
-}
\ No newline at end of file
+  IO.unzip((Compile / packageBin).value, target.value / "extracted")
+}
diff --git a/sbt-app/src/sbt-test/package/resources/src/main/scala/jartest/Main.scala b/sbt-app/src/sbt-test/package/resources/src/main/scala/jartest/Main.scala
index 1998ccc6d..4c92d0fa7 100644
--- a/sbt-app/src/sbt-test/package/resources/src/main/scala/jartest/Main.scala
+++ b/sbt-app/src/sbt-test/package/resources/src/main/scala/jartest/Main.scala
@@ -1,10 +1,6 @@
 package jartest
 
-object Main
-{
-	def main(args: Array[String])
-	{
-		if(getClass.getResource("main_resource_test") == null)
-			System.exit(1)
-	}
-}
\ No newline at end of file
+object Main:
+  def main(args: Array[String]): Unit =
+    if(getClass.getResource("main_resource_test") == null)
+      System.exit(1)
diff --git a/sbt-app/src/sbt-test/project/auto-import/project/P.scala b/sbt-app/src/sbt-test/project/auto-import/project/P.scala
index 70e309a38..38b2f9949 100644
--- a/sbt-app/src/sbt-test/project/auto-import/project/P.scala
+++ b/sbt-app/src/sbt-test/project/auto-import/project/P.scala
@@ -22,8 +22,8 @@ package name.example {
 
     import autoImport._
     override def projectSettings = Seq[Setting[_]](
-      checkMaxErrors := (Keys.maxErrors map { me => assert(me == xyz, "Expected maxErrors to be " + xyz + ", but it was " + me ) }).value,
-      checkName := (Keys.name map { n => assert(n == "Demo", "Expected name to be 'Demo', but it was '" + n + "'" ) }).value
+      checkMaxErrors := (Keys.maxErrors mapN { me => assert(me == xyz, "Expected maxErrors to be " + xyz + ", but it was " + me ) }).value,
+      checkName := (Keys.name mapN { n => assert(n == "Demo", "Expected name to be 'Demo', but it was '" + n + "'" ) }).value
     )
   }
 }
diff --git a/sbt-app/src/sbt-test/project/auto-plugins-default-requires-jvmplugin/build.sbt b/sbt-app/src/sbt-test/project/auto-plugins-default-requires-jvmplugin/build.sbt
index bea5471fd..a6062b24c 100644
--- a/sbt-app/src/sbt-test/project/auto-plugins-default-requires-jvmplugin/build.sbt
+++ b/sbt-app/src/sbt-test/project/auto-plugins-default-requires-jvmplugin/build.sbt
@@ -1,5 +1,5 @@
 val test123 = project in file(".") enablePlugins TestP settings(
-  resourceGenerators in Compile += Def.task {
+  Compile / resourceGenerators += Def.task {
     streams.value.log info "resource generated in settings"
     Nil
   }
diff --git a/sbt-app/src/sbt-test/project/auto-plugins-default-requires-jvmplugin/project/TestP.scala b/sbt-app/src/sbt-test/project/auto-plugins-default-requires-jvmplugin/project/TestP.scala
index c52417af9..7b4cad897 100644
--- a/sbt-app/src/sbt-test/project/auto-plugins-default-requires-jvmplugin/project/TestP.scala
+++ b/sbt-app/src/sbt-test/project/auto-plugins-default-requires-jvmplugin/project/TestP.scala
@@ -2,7 +2,7 @@ import sbt._, Keys._
 
 object TestP extends AutoPlugin {
   override def projectSettings: Seq[Setting[_]] = Seq(
-    resourceGenerators in Compile += Def.task {
+    Compile / resourceGenerators += Def.task {
       streams.value.log info "resource generated in plugin"
       Nil
     }
diff --git a/sbt-app/src/sbt-test/project/auto-plugins/build.sbt b/sbt-app/src/sbt-test/project/auto-plugins/build.sbt
index f564d4879..60025752b 100644
--- a/sbt-app/src/sbt-test/project/auto-plugins/build.sbt
+++ b/sbt-app/src/sbt-test/project/auto-plugins/build.sbt
@@ -29,44 +29,44 @@ lazy val projI = project.enablePlugins(TopC)
 lazy val disableAutoNoRequirePlugin = project.disablePlugins(OrgPlugin)
 
 check := {
-    // Ensure organization on root is overridable.
-    val rorg = (organization).value // Should be None
-    same(rorg, "override", "organization")
-    // this will pass when the raw disablePlugin works.
-    val dversion = (projectID in projD).?.value // Should be None
-    same(dversion, None, "projectID in projD")
+  // Ensure organization on root is overridable.
+  val rorg = (organization).value // Should be None
+  same(rorg, "override", "organization")
+  // this will pass when the raw disablePlugin works.
+  val dversion = (projD / projectID).?.value // Should be None
+  same(dversion, None, "projectID in projD")
 
-//  Ensure with multiple .sbt files that disabling/enabling works across them
-    val fDel = (del in Quux in projF).?.value
-    same(fDel, Some(" Q"), "del in Quux in projF")
-//
-	val adel = (del in projA).?.value // should be None
-	same(adel, None, "del in projA")
-	val bdel = (del in projB).?.value // should be None
-	same(bdel, None, "del in projB")
-	val ddel = (del in projD).?.value // should be None
-	same(ddel, None, "del in projD")
-//
-	val buildValue = (demo in ThisBuild).value
-	same(buildValue, "build 0", "demo in ThisBuild")
-	val globalValue = (demo in Global).value
-	same(globalValue, "global 0", "demo in Global")
-	val projValue = (demo in projC).?.value
-	same(projValue, Some("project projC Q R"), "demo in projC")
-	val qValue = (del in projC in Quux).?.value
-	same(qValue, Some(" Q R"), "del in projC in Quux")
-	val optInValue = (del in projE in Quux).value
-	same(optInValue, " Q S R", "del in projE in Quux")
-	val overrideOrgValue = (organization in projE).value
-	same(overrideOrgValue, "S", "organization in projE")
-// tests for top level plugins
-  val topLevelAValueG = (topLevelDemo in projG).value
+  //  Ensure with multiple .sbt files that disabling/enabling works across them
+  val fDel = (projF / Quux / del).?.value
+  same(fDel, Some(" Q"), "del in Quux in projF")
+  //
+  val adel = (projA / del).?.value // should be None
+  same(adel, None, "del in projA")
+  val bdel = (projB / del).?.value // should be None
+  same(bdel, None, "del in projB")
+  val ddel = (projD / del).?.value // should be None
+  same(ddel, None, "del in projD")
+  //
+  val buildValue = (ThisBuild / demo).value
+  same(buildValue, "build 0", "demo in ThisBuild")
+  val globalValue = (Global / demo).value
+  same(globalValue, "global 0", "demo in Global")
+  val projValue = (projC / demo).?.value
+  same(projValue, Some("project projC Q R"), "demo in projC")
+  val qValue = (Quux / del in projC)(projC / del).?.value
+  same(qValue, Some(" Q R"), "del in projC in Quux")
+  val optInValue = (Quux / del in projE)(projE / del).value
+  same(optInValue, " Q S R", "del in projE in Quux")
+  val overrideOrgValue = (projE / organization).value
+  same(overrideOrgValue, "S", "organization in projE")
+  // tests for top level plugins
+  val topLevelAValueG = (projG / topLevelDemo).value
   same(topLevelAValueG, "TopA: topLevelDemo project projG", "topLevelDemo in projG")
-  val demoValueG = (demo in projG).value
+  val demoValueG = (projG / demo).value
   same(demoValueG, "TopA: demo project projG", "demo in projG")
-  val topLevelBValueH = (topLevelDemo in projH).value
+  val topLevelBValueH = (projH / topLevelDemo).value
   same(topLevelBValueH, "TopB: topLevelDemo project projH", "topLevelDemo in projH")
-  val hdel = (del in projH).?.value
+  val hdel = (projH / del).?.value
   same(hdel, None, "del in projH")
 }
 
@@ -75,5 +75,5 @@ keyTest := "foo"
 topLevelKeyTest := "bar"
 
 def same[T](actual: T, expected: T, label: String): Unit = {
-	assert(actual == expected, s"Expected '$expected' for `$label`, got '$actual'")
+  assert(actual == expected, s"Expected '$expected' for `$label`, got '$actual'")
 }
diff --git a/sbt-app/src/sbt-test/project/auto-plugins/project/Q.scala b/sbt-app/src/sbt-test/project/auto-plugins/project/Q.scala
index 001fd1eae..40bbc3569 100644
--- a/sbt-app/src/sbt-test/project/auto-plugins/project/Q.scala
+++ b/sbt-app/src/sbt-test/project/auto-plugins/project/Q.scala
@@ -1,97 +1,92 @@
 package sbttest // you need package https://stackoverflow.com/questions/9822008/
 
-	import sbt._, Keys._
-	import java.util.concurrent.atomic.{AtomicInteger => AInt}
+import sbt._, Keys._
+import java.util.concurrent.atomic.{AtomicInteger => AInt}
 
-	object A extends AutoPlugin { override def requires: Plugins = empty }
-	object B extends AutoPlugin { override def requires: Plugins = empty }
-	object E extends AutoPlugin { override def requires: Plugins = empty }
+object A extends AutoPlugin { override def requires: Plugins = empty }
+object B extends AutoPlugin { override def requires: Plugins = empty }
+object E extends AutoPlugin { override def requires: Plugins = empty }
 
-object Imports
-{
-	lazy val Quux = config("q")
-	lazy val Pippy = config("p").extend(Quux)
+object Imports {
+  lazy val Quux = config("q")
+  lazy val Pippy = config("p").extend(Quux)
 
-	lazy val demo = settingKey[String]("A demo setting.")
-	lazy val del = settingKey[String]("Another demo setting.")
+  lazy val demo = settingKey[String]("A demo setting.")
+  lazy val del = settingKey[String]("Another demo setting.")
 
-	lazy val check = taskKey[Unit]("Verifies settings are as they should be.")
+  lazy val check = taskKey[Unit]("Verifies settings are as they should be.")
 }
 
-object OrgPlugin extends AutoPlugin {
-	override def trigger = allRequirements
-	override def requires: Plugins = empty
-	override def projectSettings = Seq(
+object OrgPlugin extends AutoPlugin:
+  override def trigger = allRequirements
+  override def requires: Plugins = empty
+  override def projectSettings = Seq(
       organization := "override"
-	)
-}
+  )
 
 object X extends AutoPlugin {
-	val autoImport = Imports
+  val autoImport = Imports
 }
 
-	import Imports._
+import Imports._
 
 object D extends AutoPlugin {
-	override def requires: Plugins = E
-	override def trigger = allRequirements
+  override def requires: Plugins = E
+  override def trigger = allRequirements
 
-	object autoImport {
-		lazy val keyTest = settingKey[String]("Another demo setting.")
-	}
+  object autoImport {
+    lazy val keyTest = settingKey[String]("Another demo setting.")
+  }
 }
 
-object Q extends AutoPlugin
-{
-	override def requires: Plugins = A && B
-	override def trigger = allRequirements
+object Q extends AutoPlugin {
+  override def requires: Plugins = A && B
+  override def trigger = allRequirements
 
-	override def projectConfigurations: Seq[Configuration] =
-		Pippy ::
-		Quux ::
-		Nil
+  override def projectConfigurations: Seq[Configuration] =
+    Pippy ::
+    Quux ::
+    Nil
 
    override def projectSettings: Seq[Setting[_]] =
-		(demo := s"project ${name.value}") ::
-		(del in Quux := " Q") ::
-		Nil
+    (demo := s"project ${name.value}") ::
+    (Quux / del := " Q") ::
+    Nil
 
    override def buildSettings: Seq[Setting[_]] =
-		(demo := s"build ${buildCount.getAndIncrement}") ::
-		Nil
+    (demo := s"build ${buildCount.getAndIncrement}") ::
+    Nil
 
    override def globalSettings: Seq[Setting[_]] =
-		(demo := s"global ${globalCount.getAndIncrement}") ::
-		Nil
+    (demo := s"global ${globalCount.getAndIncrement}") ::
+    Nil
 
-	// used to ensure the build-level and global settings are only added once
-	private[this] val buildCount = new AInt(0)
-	private[this] val globalCount = new AInt(0)
+  // used to ensure the build-level and global settings are only added once
+  private[this] val buildCount = new AInt(0)
+  private[this] val globalCount = new AInt(0)
 }
 
-object R extends AutoPlugin
-{
-	// NOTE - Only plugins themselves support exclusions...
-	override def requires = Q
-	override def trigger = allRequirements
+object R extends AutoPlugin {
+  // NOTE - Only plugins themselves support exclusions...
+  override def requires = Q
+  override def trigger = allRequirements
 
-	override def projectSettings = Seq(
-		// tests proper ordering: R requires Q, so Q settings should come first
-		del in Quux += " R",
-		// tests that configurations are properly registered, enabling delegation from p to q
-		demo += (del in Pippy).value
-	)
+  override def projectSettings = Seq(
+    // tests proper ordering: R requires Q, so Q settings should come first
+    Quux / del += " R",
+    // tests that configurations are properly registered, enabling delegation from p to q
+    demo += (del in Pippy).value
+  )
 }
 
 // This is an opt-in plugin with a requirement
 // Unless explicitly loaded by the build user, this will not be activated.
-object S extends AutoPlugin
-{
-	override def requires = Q
-	override def trigger = noTrigger
+object S extends AutoPlugin {
+  override def requires = Q
+  override def trigger = noTrigger
 
-	override def projectSettings = Seq(
-		del in Quux += " S",
-		organization := "S"
-	)
+  override def projectSettings = Seq(
+    Quux / del += " S",
+    organization := "S"
+  )
 }
diff --git a/sbt-app/src/sbt-test/project/binary-plugin/common.sbt b/sbt-app/src/sbt-test/project/binary-plugin/common.sbt
index 4b30c03d6..6d24d8274 100644
--- a/sbt-app/src/sbt-test/project/binary-plugin/common.sbt
+++ b/sbt-app/src/sbt-test/project/binary-plugin/common.sbt
@@ -1,7 +1,5 @@
-organization in ThisBuild := "org.example"
+ThisBuild / organization := "org.example"
 
 // We have to use snapshot because this is publishing to our local ivy cache instead of
 // an integration cache, so we're in danger land.
-version in ThisBuild := "3.4-SNAPSHOT"
-
-
+ThisBuild / version := "3.4-SNAPSHOT"
diff --git a/sbt-app/src/sbt-test/project/build-deps/changes/b.sbt b/sbt-app/src/sbt-test/project/build-deps/changes/b.sbt
index 334917dea..80ff9307e 100644
--- a/sbt-app/src/sbt-test/project/build-deps/changes/b.sbt
+++ b/sbt-app/src/sbt-test/project/build-deps/changes/b.sbt
@@ -1,5 +1,5 @@
-buildDependencies in Global :=
-  (buildDependencies in Global).value.addClasspath(
-    (thisProjectRef in LocalProject("a")).value,
+Global / buildDependencies :=
+  (Global / buildDependencies).value.addClasspath(
+    (LocalProject("a") / thisProjectRef).value,
     ResolvedClasspathDependency(thisProjectRef.value, None)
   )
diff --git a/sbt-app/src/sbt-test/project/circular/build.sbt b/sbt-app/src/sbt-test/project/circular/build.sbt
index f254811cc..da3f9877c 100644
--- a/sbt-app/src/sbt-test/project/circular/build.sbt
+++ b/sbt-app/src/sbt-test/project/circular/build.sbt
@@ -7,12 +7,12 @@ lazy val root = (project in file(".")).
 lazy val sub: Project = project.
   dependsOn(LocalProject("root")).
   settings(
-    name := (name in LocalProject("root")).value + "sub"
+    name := (LocalProject("root") / name).value + "sub"
   )
 
 lazy val foo: Project = project.
   aggregate(LocalProject("root")).
   dependsOn(LocalProject("root")).
   settings(List(
-    name := (name in LocalProject("root")).value + "foo"
+    name := (LocalProject("root") / name).value + "foo"
   ): _*)
diff --git a/sbt-app/src/sbt-test/project/cross-plugins-defaults/build.sbt b/sbt-app/src/sbt-test/project/cross-plugins-defaults/build.sbt
index 2179dcf9e..07ff57632 100644
--- a/sbt-app/src/sbt-test/project/cross-plugins-defaults/build.sbt
+++ b/sbt-app/src/sbt-test/project/cross-plugins-defaults/build.sbt
@@ -1,8 +1,8 @@
 val baseSbt = "1."
 
 val buildCrossList = List("2.10.7", "2.11.12", "2.12.12")
-scalaVersion in ThisBuild := "2.12.12"
-crossScalaVersions in ThisBuild := buildCrossList
+(ThisBuild / scalaVersion) := "2.12.12"
+(ThisBuild / crossScalaVersions) := buildCrossList
 
 addSbtPlugin("com.eed3si9n" % "sbt-buildinfo" % "0.7.0")
 
@@ -16,8 +16,8 @@ lazy val root = (project in file("."))
 lazy val app = (project in file("app"))
 
 def mkCheck(scalaBinV: String, sbtBinVer: String, sbtVerPrefix: String) = Def.task {
-  val crossV = (sbtVersion in pluginCrossBuild).value
-  val crossBinV = (sbtBinaryVersion in pluginCrossBuild).value
+  val crossV = (pluginCrossBuild / sbtVersion).value
+  val crossBinV = (pluginCrossBuild / sbtBinaryVersion).value
   val sv = projectID.value.extraAttributes("e:scalaVersion")
   assert(sbtVersion.value startsWith baseSbt, s"Wrong sbt version: ${sbtVersion.value}")
   assert(sv == scalaBinV, s"Wrong e:scalaVersion: $sv")
@@ -33,8 +33,8 @@ def mkCheck(scalaBinV: String, sbtBinVer: String, sbtVerPrefix: String) = Def.ta
   assert(plugSbtV == sbtBinVer, s"Wrong plugin sbtVersion: $plugSbtV")
 
   // crossScalaVersions in app should not be affected, per se or after ^^
-  val appCrossScalaVersions = (crossScalaVersions in app).value.toList
-  val appScalaVersion = (scalaVersion in app).value
+  val appCrossScalaVersions = (app / crossScalaVersions).value.toList
+  val appScalaVersion = (app / scalaVersion).value
   assert(appCrossScalaVersions == buildCrossList, s"Wrong `crossScalaVersions in app`: $appCrossScalaVersions")
   assert(appScalaVersion startsWith "2.12", s"Wrong `scalaVersion in app`: $appScalaVersion")
 }
diff --git a/sbt-app/src/sbt-test/project/cross-plugins-source/build.sbt b/sbt-app/src/sbt-test/project/cross-plugins-source/build.sbt
index 874d2da9d..5bb39c396 100644
--- a/sbt-app/src/sbt-test/project/cross-plugins-source/build.sbt
+++ b/sbt-app/src/sbt-test/project/cross-plugins-source/build.sbt
@@ -1,6 +1,6 @@
 lazy val root = (project in file("."))
   .settings(
     sbtPlugin := true,
-    sbtVersion in pluginCrossBuild := "0.13.15",
+    pluginCrossBuild / sbtVersion := "0.13.15",
     resolvers += Resolver.typesafeIvyRepo("releases")
   )
diff --git a/sbt-app/src/sbt-test/project/generated-root-no-publish/build.sbt b/sbt-app/src/sbt-test/project/generated-root-no-publish/build.sbt
index 218d90089..d97e40622 100644
--- a/sbt-app/src/sbt-test/project/generated-root-no-publish/build.sbt
+++ b/sbt-app/src/sbt-test/project/generated-root-no-publish/build.sbt
@@ -3,7 +3,7 @@ ThisBuild / csrCacheDirectory := (ThisBuild / baseDirectory).value / "coursier-c
 val commonSettings = Seq(
   organization := "com.example",
   version := "0.1.0",
-  ivyPaths := IvyPaths((baseDirectory in LocalRootProject).value, Some((target in LocalRootProject).value / "ivy-cache"))
+  ivyPaths := IvyPaths((LocalRootProject / baseDirectory).value, Some((LocalRootProject / target).value / "ivy-cache"))
 )
 
 lazy val app = (project in file("app")).
diff --git a/sbt-app/src/sbt-test/project/lint/build.sbt b/sbt-app/src/sbt-test/project/lint/build.sbt
index b8ba55e05..bdf757b50 100644
--- a/sbt-app/src/sbt-test/project/lint/build.sbt
+++ b/sbt-app/src/sbt-test/project/lint/build.sbt
@@ -12,8 +12,8 @@ lazy val root = (project in file("."))
   .settings(
     lintBuildTest := {
       val state = Keys.state.value
-      val includeKeys = (lintIncludeFilter in Global).value
-      val excludeKeys = (lintExcludeFilter in Global).value
+      val includeKeys = (Global / lintIncludeFilter).value
+      val excludeKeys = (Global / lintExcludeFilter).value
       val result = sbt.internal.LintUnused.lintUnused(state, includeKeys, excludeKeys)
       result foreach {
         case (_, "ThisBuild / doc / scalacOptions", _) => ()
diff --git a/sbt-app/src/sbt-test/project/load-hooks/build.sbt b/sbt-app/src/sbt-test/project/load-hooks/build.sbt
index c5d44543c..9e12fedd5 100644
--- a/sbt-app/src/sbt-test/project/load-hooks/build.sbt
+++ b/sbt-app/src/sbt-test/project/load-hooks/build.sbt
@@ -6,8 +6,8 @@
     s.put(key, previous + 1)
   }
   Seq(
-    onLoad in Global ~= (f(loadCount) compose _),
-    onUnload in Global ~= (f(unloadCount) compose _)
+    Global / onLoad ~= (f(loadCount) compose _),
+    Global / onUnload ~= (f(unloadCount) compose _)
   )
 }
 
diff --git a/sbt-app/src/sbt-test/project/provided/build.sbt b/sbt-app/src/sbt-test/project/provided/build.sbt
index af6bf0a3f..49a4c3edb 100644
--- a/sbt-app/src/sbt-test/project/provided/build.sbt
+++ b/sbt-app/src/sbt-test/project/provided/build.sbt
@@ -2,15 +2,17 @@ val rootRef = LocalProject("root")
 val sub = project
 val superRoot = project in file("super") dependsOn rootRef
 
-val root = project in file(".") dependsOn (sub % "provided->test") settings (
-  TaskKey[Unit]("check") := {
-    check0((fullClasspath in (sub, Test)).value, "sub test", true)
-    check0((fullClasspath in (superRoot, Compile)).value, "superRoot main", false)
-    check0((fullClasspath in (rootRef, Compile)).value, "root main", true)
-    check0((fullClasspath in (rootRef, Runtime)).value, "root runtime", false)
-    check0((fullClasspath in (rootRef, Test)).value, "root test", true)
-  }
-)
+val root = (project in file(".")).
+  dependsOn(sub % "provided->test").
+  settings (
+    TaskKey[Unit]("check") := {
+      check0((sub / Test / fullClasspath).value, "sub test", true)
+      check0((superRoot / Compile / fullClasspath).value, "superRoot main", false)
+      check0((rootRef / Compile / fullClasspath).value, "root main", true)
+      check0((rootRef / Runtime / fullClasspath).value, "root runtime", false)
+      check0((rootRef / Test / fullClasspath).value, "root test", true)
+    }
+  )
 
 def check0(cp: Seq[Attributed[File]], label: String, shouldSucceed: Boolean): Unit = {
   import sbt.internal.inc.classpath.ClasspathUtilities
diff --git a/sbt-app/src/sbt-test/project/sequential/build.sbt b/sbt-app/src/sbt-test/project/sequential/build.sbt
index cd4cb1eac..f4ff7fa42 100644
--- a/sbt-app/src/sbt-test/project/sequential/build.sbt
+++ b/sbt-app/src/sbt-test/project/sequential/build.sbt
@@ -34,6 +34,6 @@ lazy val root = project.
       val t = testFile.value
       IO.append(t, "2")
     },
-    foo := Def.sequential(compile in Compile, sideEffect0, sideEffect1, sideEffect2, test in Test, bar).value,
+    foo := Def.sequential(Compile / compile, sideEffect0, sideEffect1, sideEffect2, Test / test, bar).value,
     bar := 1
   )
diff --git a/sbt-app/src/sbt-test/tests/arguments/build.sbt b/sbt-app/src/sbt-test/tests/arguments/build.sbt
index 34877ddf4..ac9bfeafa 100644
--- a/sbt-app/src/sbt-test/tests/arguments/build.sbt
+++ b/sbt-app/src/sbt-test/tests/arguments/build.sbt
@@ -14,7 +14,7 @@ lazy val root = (project in file("."))
     },
     libraryDependencies += scalatest % Test,
     // testOptions in Test += Tests.Argument(TestFrameworks.ScalaTest, "-f", "result.txt", "-eNDXEHLO")
-    testOptions in Configurations.Test ++= {
+    Configurations.Test / testOptions ++= {
       def args(path: String, args: String*): Seq[TestOption] =
         if(file(path).exists) Tests.Argument(args : _*) :: Nil
         else Nil
diff --git a/sbt-app/src/sbt-test/tests/bak/build.sbt b/sbt-app/src/sbt-test/tests/bak/build.sbt
index 40b598c48..63777d713 100644
--- a/sbt-app/src/sbt-test/tests/bak/build.sbt
+++ b/sbt-app/src/sbt-test/tests/bak/build.sbt
@@ -24,22 +24,22 @@ val p1 = project
   .configs(CustomConfigs: _*)
   .settings(
     t := {
-        (compile in Config_0).value
-        (compile in Config_1).value
-        (compile in Config_2).value
-        (compile in Config_3).value
-        (compile in Config_4).value
-        (compile in Config_5).value
-        (compile in Config_6).value
-        (compile in Config_7).value
-        (compile in Config_8).value
-        (compile in Config_9).value
-        (compile in Config_10).value
-        (compile in Config_11).value
-        (compile in Config_12).value
-        (compile in Config_13).value
-        (compile in Config_14).value
-        (compile in Config_15).value
+        (Config_0 / compile).value
+        (Config_1 / compile).value
+        (Config_2 / compile).value
+        (Config_3 / compile).value
+        (Config_4 / compile).value
+        (Config_5 / compile).value
+        (Config_6 / compile).value
+        (Config_7 / compile).value
+        (Config_8 / compile).value
+        (Config_9 / compile).value
+        (Config_10 / compile).value
+        (Config_11 / compile).value
+        (Config_12 / compile).value
+        (Config_13 / compile).value
+        (Config_14 / compile).value
+        (Config_15 / compile).value
     }
   )
   .settings(CustomConfigs.flatMap(c => inConfig(c)(Defaults.testSettings)))
diff --git a/sbt-app/src/sbt-test/tests/empty/build.sbt b/sbt-app/src/sbt-test/tests/empty/build.sbt
index a4448f16f..e9ed5a04a 100644
--- a/sbt-app/src/sbt-test/tests/empty/build.sbt
+++ b/sbt-app/src/sbt-test/tests/empty/build.sbt
@@ -1,5 +1,5 @@
 testGrouping := {
-  val tests = (definedTests in Test).value
+  val tests = (Test / definedTests).value
   tests map { test =>
     new Tests.Group(
       name = test.name,
diff --git a/sbt-app/src/sbt-test/tests/fork-parallel/build.sbt b/sbt-app/src/sbt-test/tests/fork-parallel/build.sbt
index 2d60ab369..5a762a03d 100644
--- a/sbt-app/src/sbt-test/tests/fork-parallel/build.sbt
+++ b/sbt-app/src/sbt-test/tests/fork-parallel/build.sbt
@@ -7,7 +7,7 @@ val check = taskKey[Unit]("Check that tests are executed in parallel")
 lazy val root = (project in file("."))
   .settings(
     libraryDependencies += "com.novocode" % "junit-interface" % "0.11" % Test,
-    fork in Test := true,
+    Test / fork := true,
     check := {
       val nbProc = java.lang.Runtime.getRuntime().availableProcessors()
       val log = streams.value.log
diff --git a/sbt-app/src/sbt-test/tests/fork-uncaught2/build.sbt b/sbt-app/src/sbt-test/tests/fork-uncaught2/build.sbt
index 2eba9d278..533b61158 100644
--- a/sbt-app/src/sbt-test/tests/fork-uncaught2/build.sbt
+++ b/sbt-app/src/sbt-test/tests/fork-uncaught2/build.sbt
@@ -6,7 +6,7 @@ testFrameworks := new TestFramework("build.MyFramework") :: Nil
 
 fork := true
 
-definedTests in Test += new sbt.TestDefinition(
+Test / definedTests += new sbt.TestDefinition(
       "my",
       // marker fingerprint since there are no test classes
       // to be discovered by sbt:
diff --git a/sbt-app/src/sbt-test/tests/fork/build.sbt b/sbt-app/src/sbt-test/tests/fork/build.sbt
index 77c74e51b..bfefc042b 100644
--- a/sbt-app/src/sbt-test/tests/fork/build.sbt
+++ b/sbt-app/src/sbt-test/tests/fork/build.sbt
@@ -16,8 +16,8 @@ ThisBuild / organization := "org.example"
 
 lazy val root = (project in file("."))
   .settings(
-    testGrouping in Test := {
-      val tests = (definedTests in Test).value
+    Test / testGrouping := {
+      val tests = (Test / definedTests).value
       assert(tests.size == 3)
       for (idx <- 0 until groups) yield
         new Group(
@@ -32,7 +32,7 @@ lazy val root = (project in file("."))
           file(groupPrefix(i) + j)
       val (exist, absent) = files.partition(_.exists)
       exist.foreach(_.delete())
-      if(absent.nonEmpty)
+      if (absent.nonEmpty)
         sys.error("Files were not created:\n\t" + absent.mkString("\n\t"))
     },
     concurrentRestrictions := Tags.limit(Tags.ForkedTestGroup, 2) :: Nil,
diff --git a/sbt-app/src/sbt-test/tests/junit/test b/sbt-app/src/sbt-test/tests/junit/test
index 73534741b..60912fdb7 100644
--- a/sbt-app/src/sbt-test/tests/junit/test
+++ b/sbt-app/src/sbt-test/tests/junit/test
@@ -10,5 +10,5 @@ $ copy-file changes/Failure.scala src/test/scala/Failure.scala
 -> testOnly com.foo.junit.test.blah.Failure
 > testOnly com.foo.junit.test.blah.Success
 
-> set fork in Test := true
+> set Test / fork := true
 > testOnly com.foo.junit.test.blah.Success
diff --git a/sbt-app/src/sbt-test/tests/set-every/build.sbt b/sbt-app/src/sbt-test/tests/set-every/build.sbt
index 718db97a1..8423f693f 100644
--- a/sbt-app/src/sbt-test/tests/set-every/build.sbt
+++ b/sbt-app/src/sbt-test/tests/set-every/build.sbt
@@ -3,14 +3,14 @@ val a = project.settings(version := "2.8.1")
 val trySetEvery = taskKey[Unit]("Tests \"set every\"")
 
 trySetEvery := {
-        val s = state.value
-        val extracted = Project.extract(s)
-        import extracted._
-        val allProjs = structure.allProjectRefs
-        val Some(aProj) = allProjs.find(_.project == "a")
-        val aVer = (version in aProj get structure.data).get
-        if (aVer != "1.0") {
-          println("Version of project a: " + aVer + ", expected: 1.0")
-          sys.error("\"set every\" did not change the version of all projects.")
-        }
+  val s = state.value
+  val extracted = Project.extract(s)
+  import extracted._
+  val allProjs = structure.allProjectRefs
+  val Some(aProj) = allProjs.find(_.project == "a")
+  val aVer = ((aProj / version) get structure.data).get
+  if (aVer != "1.0") {
+    println("Version of project a: " + aVer + ", expected: 1.0")
+    sys.error("\"set every\" did not change the version of all projects.")
+  }
 }
diff --git a/sbt-app/src/sbt-test/watch/custom-config/project/Build.scala b/sbt-app/src/sbt-test/watch/custom-config/project/Build.scala
index 7d88ac738..cc75af3a9 100644
--- a/sbt-app/src/sbt-test/watch/custom-config/project/Build.scala
+++ b/sbt-app/src/sbt-test/watch/custom-config/project/Build.scala
@@ -16,29 +16,34 @@ object Build {
     val Seq(stringFile, string) = Def.spaceDelimited().parsed
     assert(IO.read(file(stringFile)) == string)
   }
-  lazy val foo = project.settings(
-    watchStartMessage := { (count: Int, _, _) => Some(s"FOO $count") },
-    Compile / compile / watchTriggers += baseDirectory.value.toGlob / "foo.txt",
-    Compile / compile / watchStartMessage := { (count: Int, _, _) =>
-      // this checks that Compile / compile / watchStartMessage
-      // is preferred to Compile / watchStartMessage
-      val outputFile = baseDirectory.value / "foo.txt"
-      IO.write(outputFile, "compile")
-      Some(s"compile $count")
-    },
-    Compile / watchStartMessage := { (count: Int, _, _) => Some(s"Compile $count") },
-    Runtime / watchStartMessage := { (count: Int, _, _) => Some(s"Runtime $count") },
-    setStringValue := {
-      val _ = (fileInputs in (bar, setStringValue)).value
-      setStringValueImpl.evaluated
-    },
-    checkStringValue := checkStringValueImpl.evaluated,
-    watchOnFileInputEvent := { (_, _) => Watch.CancelWatch }
-  )
-  lazy val bar = project.settings(
-    fileInputs in setStringValue += baseDirectory.value.toGlob / "foo.txt"
-  )
-  lazy val root = (project in file(".")).aggregate(foo, bar).settings(
-    watchOnFileInputEvent := { (_, _) => Watch.CancelWatch }
-  )
+  lazy val foo = project
+    .settings(
+      watchStartMessage := { (count: Int, _, _) => Some(s"FOO $count") },
+      Compile / compile / watchTriggers += baseDirectory.value.toGlob / "foo.txt",
+      Compile / compile / watchStartMessage := { (count: Int, _, _) =>
+        // this checks that Compile / compile / watchStartMessage
+        // is preferred to Compile / watchStartMessage
+        val outputFile = baseDirectory.value / "foo.txt"
+        IO.write(outputFile, "compile")
+        Some(s"compile $count")
+      },
+      Compile / watchStartMessage := { (count: Int, _, _) => Some(s"Compile $count") },
+      Runtime / watchStartMessage := { (count: Int, _, _) => Some(s"Runtime $count") },
+      setStringValue := {
+        val _ = (bar / setStringValue / fileInputs).value
+        setStringValueImpl.evaluated
+      },
+      checkStringValue := checkStringValueImpl.evaluated,
+      watchOnFileInputEvent := { (_, _) => Watch.CancelWatch }
+    )
+
+  lazy val bar = project
+    .settings(
+      setStringValue / fileInputs += baseDirectory.value.toGlob / "foo.txt"
+    )
+
+  lazy val root = (project in file("."))
+    .aggregate(foo, bar).settings(
+      watchOnFileInputEvent := { (_, _) => Watch.CancelWatch }
+    )
 }
diff --git a/sbt-app/src/sbt-test/watch/file-input-aggregation/project/Build.scala b/sbt-app/src/sbt-test/watch/file-input-aggregation/project/Build.scala
index 32b999320..2f42332a4 100644
--- a/sbt-app/src/sbt-test/watch/file-input-aggregation/project/Build.scala
+++ b/sbt-app/src/sbt-test/watch/file-input-aggregation/project/Build.scala
@@ -33,7 +33,7 @@ object Build {
   lazy val foo = project
     .settings(
       setStringValue := {
-        val _ = (fileInputs in (bar, setStringValue)).value
+        val _ = (bar / setStringValue / fileInputs).value
         setStringValueImpl.evaluated
       },
       checkStringValue := checkStringValueImpl.evaluated,
@@ -92,6 +92,7 @@ object Build {
       assert(testTriggers == compileTriggers)
     },
   )
+
   lazy val root = (project in file("."))
     .aggregate(foo, bar)
     .settings(