diff --git a/compile/api/ClassToAPI.scala b/compile/api/ClassToAPI.scala
index ccb6640b0..81f18b761 100644
--- a/compile/api/ClassToAPI.scala
+++ b/compile/api/ClassToAPI.scala
@@ -7,6 +7,7 @@ import xsbti.api
 import xsbti.SafeLazy
 import SafeLazy.strict
 import collection.mutable
+import scala.reflect.ClassTag
 
 object ClassToAPI
 {
@@ -18,7 +19,7 @@ object ClassToAPI
 	}
 
 	// Avoiding implicit allocation.
-	private def arrayMap[T <: AnyRef, U <: AnyRef : ClassManifest](xs: Array[T])(f: T => U): Array[U] = {
+	private def arrayMap[T <: AnyRef, U <: AnyRef : ClassTag](xs: Array[T])(f: T => U): Array[U] = {
 	  val len = xs.length
 	  var i = 0
 	  val res = new Array[U](len)
diff --git a/main/Defaults.scala b/main/Defaults.scala
index 117f8da1d..3f4900ae8 100755
--- a/main/Defaults.scala
+++ b/main/Defaults.scala
@@ -55,17 +55,17 @@ object Defaults extends BuildCommon
 		managedDirectory <<= baseDirectory(_ / "lib_managed")
 	))
 	def globalCore: Seq[Setting[_]] = inScope(GlobalScope)(defaultTestTasks(test) ++ defaultTestTasks(testOnly) ++ defaultTestTasks(testQuick) ++ Seq(
-		compilerCache <<= state map { _ get Keys.stateCompilerCache getOrElse compiler.CompilerCache.fresh },
+		compilerCache := state.value get Keys.stateCompilerCache getOrElse compiler.CompilerCache.fresh,
 		crossVersion :== CrossVersion.Disabled,
 		scalaOrganization :== ScalaArtifacts.Organization,
 		buildDependencies <<= buildDependencies or Classpaths.constructBuildDependencies,
 		taskTemporaryDirectory := { val dir = IO.createTemporaryDirectory; dir.deleteOnExit(); dir },
-		onComplete <<= taskTemporaryDirectory { dir => () => IO.delete(dir); IO.createDirectory(dir) },
+		onComplete := { val dir = taskTemporaryDirectory.value; () => IO.delete(dir); IO.createDirectory(dir) },
 		concurrentRestrictions <<= concurrentRestrictions or defaultRestrictions,
 		parallelExecution :== true,
-		sbtVersion <<= appConfiguration { _.provider.id.version },
-		sbtBinaryVersion <<= sbtVersion apply binarySbtVersion,
-		sbtResolver <<= sbtVersion { sbtV => if(sbtV endsWith "-SNAPSHOT") Classpaths.typesafeSnapshots else Classpaths.typesafeReleases },
+		sbtVersion := appConfiguration.value.provider.id.version,
+		sbtBinaryVersion := binarySbtVersion(sbtVersion.value),
+		sbtResolver := { if(sbtVersion.value endsWith "-SNAPSHOT") Classpaths.typesafeSnapshots else Classpaths.typesafeReleases },
 		pollInterval :== 500,
 		logBuffered :== false,
 		connectInput :== false,
@@ -74,7 +74,7 @@ object Defaults extends BuildCommon
 		autoScalaLibrary :== true,
 		onLoad <<= onLoad ?? idFun[State],
 		onUnload <<= (onUnload ?? idFun[State]),
-		onUnload <<= (onUnload, taskTemporaryDirectory) { (f, dir) => s => { try f(s) finally IO.delete(dir) } },
+		onUnload := { s => try onUnload.value(s) finally IO.delete(taskTemporaryDirectory.value) },
 		watchingMessage <<= watchingMessage ?? Watched.defaultWatchingMessage,
 		triggeredMessage <<= triggeredMessage ?? Watched.defaultTriggeredMessage,
 		definesClass :== FileValueCache(Locate.definesClass _ ).get,
@@ -109,12 +109,12 @@ object Defaults extends BuildCommon
 		showSuccess :== true,
 		commands :== Nil,
 		retrieveManaged :== false,
-		buildStructure <<= state map Project.structure,
-		settings <<= buildStructure map ( _.data ),
+		buildStructure := Project.structure(state.value),
+		settings := buildStructure.value.data,
 		artifactClassifier :== None,
 		artifactClassifier in packageSrc :== Some(SourceClassifier),
 		artifactClassifier in packageDoc :== Some(DocClassifier),
-		checksums <<= appConfiguration(Classpaths.bootChecksums),
+		checksums := Classpaths.bootChecksums(appConfiguration.value),
 		pomExtra :== NodeSeq.Empty,
 		pomPostProcess :== idFun,
 		pomAllRepositories :== false,
@@ -130,44 +130,44 @@ object Defaults extends BuildCommon
 		logBuffered := true
 	))
 	def projectCore: Seq[Setting[_]] = Seq(
-		name <<= thisProject(_.id),
-		logManager <<= extraLoggers(extra => LogManager.defaults(extra, StandardMain.console)),
+		name := thisProject.value.id,
+		logManager := LogManager.defaults(extraLoggers.value, StandardMain.console),
 		onLoadMessage <<= onLoadMessage or (name, thisProjectRef)("Set current project to " + _ + " (in build " + _.build +")"),
 		runnerTask
 	)
 	def paths = Seq(
-		baseDirectory <<= thisProject(_.base),
-		target <<= baseDirectory / "target",
+		baseDirectory := thisProject.value.base,
+		target := baseDirectory.value / "target",
 		historyPath <<= historyPath or target(t => Some(t / ".history")),
-		sourceDirectory <<= baseDirectory / "src",
-		sourceManaged <<= crossTarget / "src_managed",
-		resourceManaged <<= crossTarget / "resource_managed",
-		cacheDirectory <<= (crossTarget, thisProject)(_ / CacheDirectoryName / _.id / "global")
+		sourceDirectory := baseDirectory.value / "src",
+		sourceManaged := crossTarget.value / "src_managed",
+		resourceManaged := crossTarget.value / "resource_managed",
+		cacheDirectory := crossTarget.value / CacheDirectoryName / thisProject.value.id / "global"
 	)
 
 	lazy val configPaths = sourceConfigPaths ++ resourceConfigPaths ++ outputConfigPaths
 	lazy val sourceConfigPaths = Seq(
 		sourceDirectory <<= configSrcSub(sourceDirectory),
 		sourceManaged <<= configSrcSub(sourceManaged),
-		scalaSource <<= sourceDirectory / "scala",
-		javaSource <<= sourceDirectory / "java",
-		unmanagedSourceDirectories <<= Seq(scalaSource, javaSource).join,
+		scalaSource := sourceDirectory.value / "scala",
+		javaSource := sourceDirectory.value / "java",
+		unmanagedSourceDirectories := Seq(scalaSource.value, javaSource.value),
 			// remove when sourceFilter, defaultExcludes are removed
 		includeFilter in unmanagedSources <<= (sourceFilter in unmanagedSources) or (includeFilter in unmanagedSources),
 		excludeFilter in unmanagedSources <<= (defaultExcludes in unmanagedSources) or (excludeFilter in unmanagedSources),
 		unmanagedSources <<= collectFiles(unmanagedSourceDirectories, includeFilter in unmanagedSources, excludeFilter in unmanagedSources),
 		watchSources in ConfigGlobal <++= unmanagedSources,
-		managedSourceDirectories <<= Seq(sourceManaged).join,
+		managedSourceDirectories := Seq(sourceManaged.value),
 		managedSources <<= generate(sourceGenerators),
 		sourceGenerators :== Nil,
 		sourceDirectories <<= Classpaths.concatSettings(unmanagedSourceDirectories, managedSourceDirectories),
 		sources <<= Classpaths.concat(unmanagedSources, managedSources)
 	)
 	lazy val resourceConfigPaths = Seq(
-		resourceDirectory <<= sourceDirectory / "resources",
+		resourceDirectory := sourceDirectory.value / "resources",
 		resourceManaged <<= configSrcSub(resourceManaged),
-		unmanagedResourceDirectories <<= Seq(resourceDirectory).join,
-		managedResourceDirectories <<= Seq(resourceManaged).join,
+		unmanagedResourceDirectories := Seq(resourceDirectory.value),
+		managedResourceDirectories := Seq(resourceManaged.value),
 		resourceDirectories <<= Classpaths.concatSettings(unmanagedResourceDirectories, managedResourceDirectories),
 			// remove when defaultExcludes are removed
 		excludeFilter in unmanagedResources <<= (defaultExcludes in unmanagedResources) or (excludeFilter in unmanagedResources),
@@ -179,13 +179,16 @@ object Defaults extends BuildCommon
 		resources <<= Classpaths.concat(managedResources, unmanagedResources)
 	)
 	lazy val outputConfigPaths = Seq(
-		cacheDirectory <<= (crossTarget, thisProject, configuration) { _ / CacheDirectoryName / _.id / _.name },
-		classDirectory <<= (crossTarget, configuration) { (outDir, conf) => outDir / (prefix(conf.name) + "classes") },
-		docDirectory <<= (crossTarget, configuration) { (outDir, conf) => outDir / (prefix(conf.name) + "api") }
+		cacheDirectory := crossTarget.value / CacheDirectoryName / thisProject.value.id / configuration.value.name,
+		classDirectory := crossTarget.value / (prefix(configuration.value.name) + "classes"),
+		docDirectory := crossTarget.value / (prefix(configuration.value.name) + "api")
 	)
 	def addBaseSources = Seq(
-		unmanagedSources <<= (unmanagedSources, baseDirectory, includeFilter in unmanagedSources, excludeFilter in unmanagedSources, sourcesInBase) map {
-			(srcs,b,f,excl,enable) => if(enable) (srcs +++ b * (f -- excl)).get else srcs
+		unmanagedSources := {
+			val srcs = unmanagedSources.value
+			val f = (includeFilter in unmanagedSources).value
+			val excl = (excludeFilter in unmanagedSources).value
+			if(sourcesInBase.value) (srcs +++ baseDirectory.value * (f -- excl)).get else srcs
 		}
 	)
 
@@ -197,18 +200,18 @@ object Defaults extends BuildCommon
 		javacOptions in GlobalScope :== Nil,
 		scalacOptions in GlobalScope :== Nil,
 		scalaInstance <<= scalaInstanceSetting,
-		scalaVersion in GlobalScope <<= appConfiguration( _.provider.scalaProvider.version),
-		scalaBinaryVersion in GlobalScope <<= scalaVersion apply binaryScalaVersion,
-		crossVersion <<= (crossPaths) { enabled => if(enabled) CrossVersion.binary else CrossVersion.Disabled },
-		crossScalaVersions in GlobalScope <<= Seq(scalaVersion).join,
-		crossTarget <<= (target, scalaBinaryVersion, sbtBinaryVersion, sbtPlugin, crossPaths)(makeCrossTarget)
+		scalaVersion in GlobalScope := appConfiguration.value.provider.scalaProvider.version,
+		scalaBinaryVersion in GlobalScope := binaryScalaVersion(scalaVersion.value),
+		crossVersion := (if(crossPaths.value) CrossVersion.binary else CrossVersion.Disabled),
+		crossScalaVersions in GlobalScope := Seq(scalaVersion.value),
+		crossTarget := makeCrossTarget(target.value, scalaBinaryVersion.value, sbtBinaryVersion.value, sbtPlugin.value, crossPaths.value)
 	)
 	def makeCrossTarget(t: File, sv: String, sbtv: String, plugin: Boolean, cross: Boolean): File =
 	{
 		val scalaBase = if(cross) t / ("scala-" + sv) else t
 		if(plugin) scalaBase / ("sbt-" + sbtv) else scalaBase
 	}
-	def compilersSetting = compilers <<= (scalaInstance, appConfiguration, streams, classpathOptions, javaHome) map { (si, app, s, co, jh) => Compiler.compilers(si, co, jh)(app, s.log) }
+	def compilersSetting = compilers := Compiler.compilers(scalaInstance.value, classpathOptions.value, javaHome.value)(appConfiguration.value, streams.value.log)
 
 	lazy val configTasks = docTaskSettings(doc) ++ compileTaskSettings ++ compileInputsSettings ++ Seq(
 		initialCommands in GlobalScope :== "",
@@ -221,18 +224,18 @@ object Defaults extends BuildCommon
 		discoveredMainClasses <<= compile map discoverMainClasses storeAs discoveredMainClasses triggeredBy compile,
 		definedSbtPlugins <<= discoverPlugins,
 		inTask(run)(runnerTask :: Nil).head,
-		selectMainClass <<= (discoveredMainClasses, mainClass) map { (classes, explicit) => explicit orElse selectRunMain(classes) },
-		mainClass in run <<= selectMainClass in run,
-		mainClass <<= discoveredMainClasses map selectPackageMain,
+		selectMainClass := mainClass.value orElse selectRunMain(discoveredMainClasses.value),
+		mainClass in run := (selectMainClass in run).value,
+		mainClass := selectPackageMain(discoveredMainClasses.value),
 		run <<= runTask(fullClasspath, mainClass in run, runner in run),
 		runMain <<= runMainTask(fullClasspath, runner in run),
 		copyResources <<= copyResourcesTask
 	)
 
 	lazy val projectTasks: Seq[Setting[_]] = Seq(
-		cleanFiles <<= Seq(managedDirectory, target).join,
-		cleanKeepFiles <<= historyPath(_.toList),
-		clean <<= (cleanFiles, cleanKeepFiles) map doClean,
+		cleanFiles := Seq(managedDirectory.value, target.value),
+		cleanKeepFiles := historyPath.value.toList,
+		clean := doClean(cleanFiles.value, cleanKeepFiles.value),
 		consoleProject <<= consoleProjectTask,
 		watchTransitiveSources <<= watchTransitiveSourcesTask,
 		watch <<= watchSetting
@@ -276,14 +279,12 @@ object Defaults extends BuildCommon
 	}
 
 	lazy val testTasks: Seq[Setting[_]] = testTaskOptions(test) ++ testTaskOptions(testOnly) ++ testTaskOptions(testQuick) ++ Seq(
-		testLoader <<= (fullClasspath, scalaInstance, taskTemporaryDirectory) map { (cp, si, temp) => TestFramework.createTestLoader(data(cp), si, IO.createUniqueDirectory(temp)) },
+		testLoader := TestFramework.createTestLoader(data(fullClasspath.value), scalaInstance.value, IO.createUniqueDirectory(taskTemporaryDirectory.value)),
 		testFrameworks in GlobalScope :== {
 			import sbt.TestFrameworks._
 			Seq(ScalaCheck, Specs2, Specs, ScalaTest, JUnit)
 		},
-		loadedTestFrameworks <<= (testFrameworks, streams, testLoader) map { (frameworks, s, loader) =>
-			frameworks.flatMap(f => f.create(loader, s.log).map( x => (f,x)).toIterable).toMap
-		},
+		loadedTestFrameworks := testFrameworks.value.flatMap(f => f.create(testLoader.value, streams.value.log).map( x => (f,x)).toIterable).toMap,
 		definedTests <<= detectTests,
 		definedTestNames <<= definedTests map ( _.map(_.name).distinct) storeAs definedTestNames triggeredBy compile,
 		testListeners in GlobalScope :== Nil,
@@ -308,7 +309,7 @@ object Defaults extends BuildCommon
 		testListeners <<= (streams, resolvedScoped, streamsManager, logBuffered, cacheDirectory in test, testListeners in TaskGlobal) map { (s, sco, sm, buff, dir, ls) =>
 			TestLogger(s.log, testLogger(sm, test in sco.scope), buff) +: new TestStatusReporter(succeededFile(dir)) +: ls
 		},
-		testOptions <<= (testOptions in TaskGlobal, testListeners) map { (options, ls) => Tests.Listeners(ls) +: options },
+		testOptions := Tests.Listeners(testListeners.value) +: (testOptions in TaskGlobal).value,
 		testExecution <<= testExecutionTask(key),
 		testGrouping <<= testGrouping or singleTestGroup(key)
 	) )
@@ -402,7 +403,7 @@ object Defaults extends BuildCommon
 	}
 
 	lazy val packageBase: Seq[Setting[_]] = Seq(
-		artifact <<= moduleName(n => Artifact(n)),
+		artifact := Artifact(moduleName.value),
 		packageOptions in GlobalScope :== Nil,
 		artifactName in GlobalScope :== ( Artifact.artifactName _ )
 	)
@@ -410,11 +411,11 @@ object Defaults extends BuildCommon
 		inTask(packageBin)(Seq(
 			packageOptions <<= (name, version, homepage, organization, organizationName, mainClass, packageOptions) map { (name, ver, h, org, orgName, main, p) => Package.addSpecManifestAttributes(name, ver, orgName) +: Package.addImplManifestAttributes(name, ver, h, org, orgName) +: main.map(Package.MainClass.apply) ++: p })) ++
 		inTask(packageSrc)(Seq(
-			packageOptions <<= (name, version, organizationName, packageOptions) map { Package.addSpecManifestAttributes(_, _, _) +: _ })) ++
+			packageOptions := Package.addSpecManifestAttributes(name.value, version.value, organizationName.value) +: packageOptions.value )) ++
 	packageTaskSettings(packageBin, packageBinMappings) ++
 	packageTaskSettings(packageSrc, packageSrcMappings) ++
 	packageTaskSettings(packageDoc, packageDocMappings) ++
-	Seq(`package` <<= packageBin)
+	Seq(`package` := packageBin.value)
 
 	def packageBinMappings = products map { _ flatMap Path.allSubpaths }
 	def packageDocMappings = doc map { Path.allSubpaths(_).toSeq }
@@ -580,14 +581,12 @@ object Defaults extends BuildCommon
 		(dependencyClasspath, cacheDirectory, skip in compile, definesClass, compilerCache) map { (cp, cacheDir, skip, definesC, cache) =>
 			Compiler.IncSetup(analysisMap(cp), definesC, skip, cacheDir / "inc_compile", cache)
 		}
-	def compileInputsSettings: Seq[Setting[_]] = {
-		val optionsPair = TaskKey.local[(Seq[String], Seq[String])]
-		Seq(optionsPair <<= (scalacOptions, javacOptions) map Util.pairID,
-		compileInputs <<= (dependencyClasspath, sources, compilers, optionsPair, classDirectory, compileOrder, compileIncSetup, maxErrors, streams, sourcePositionMappers) map {
-			(cp, srcs, cs, optsPair, classes, order, incSetup, maxErr, s, spms) =>
-				Compiler.inputs(classes +: data(cp), srcs, classes, optsPair._1, optsPair._2, maxErr, spms, order)(cs, incSetup, s.log)
-			})
-	}
+	def compileInputsSettings: Seq[Setting[_]] =
+		Seq(compileInputs := {
+			val cp = classDirectory.value +: data(dependencyClasspath.value)
+			Compiler.inputs(cp, sources.value, classDirectory.value, scalacOptions.value, javacOptions.value, maxErrors.value, sourcePositionMappers.value, compileOrder.value)(compilers.value, compileIncSetup.value, streams.value.log)
+		})
+
 	def printWarningsTask: Initialize[Task[Unit]] =
 		(streams, compile, maxErrors, sourcePositionMappers) map { (s, analysis, max, spms) =>
 			val problems = analysis.infos.allInfos.values.flatMap(i =>  i.reportedProblems++ i.unreportedProblems)
@@ -871,7 +870,8 @@ object Classpaths
 				IvyActions.updateClassifiers(is, GetClassifiersConfiguration(mod, excludes, c, ivyScala), s.log)
 			}
 		} tag(Tags.Update, Tags.Network),
-		sbtDependency in GlobalScope <<= appConfiguration { app =>
+		sbtDependency in GlobalScope := {
+			val app = appConfiguration.value
 			val id = app.provider.id
 			val scalaVersion = app.provider.scalaProvider.version
 			val binVersion = binaryScalaVersion(scalaVersion)
@@ -902,14 +902,11 @@ object Classpaths
 
 	def sbtClassifiersTasks = inTask(updateSbtClassifiers)(Seq(
 		transitiveClassifiers in GlobalScope in updateSbtClassifiers ~= ( _.filter(_ != DocClassifier) ),
-		externalResolvers <<= (externalResolvers, appConfiguration, buildStructure, thisProjectRef) map { (defaultRs, ac, struct, ref) =>
-			val explicit = struct.units(ref.build).unit.plugins.pluginData.resolvers
-			explicit orElse bootRepositories(ac) getOrElse defaultRs
-		},
-		ivyConfiguration <<= (externalResolvers, ivyPaths, offline, checksums, appConfiguration, target, streams) map { (rs, paths, off, check, app, t, s) =>
-			val resCacheDir = t / "resolution-cache"
-			new InlineIvyConfiguration(paths, rs, Nil, Nil, off, Option(lock(app)), check, Some(resCacheDir), s.log)
+		externalResolvers := {
+			val explicit = buildStructure.value.units(thisProjectRef.value.build).unit.plugins.pluginData.resolvers
+			explicit orElse bootRepositories(appConfiguration.value) getOrElse externalResolvers.value
 		},
+		ivyConfiguration := new InlineIvyConfiguration(ivyPaths.value, externalResolvers.value, Nil, Nil, offline.value, Option(lock(appConfiguration.value)), checksums.value, Some(target.value / "resolution-cache"), streams.value.log),
 		ivySbt <<= ivySbt0,
 		classifiersModule <<= (projectID, sbtDependency, transitiveClassifiers, loadedBuild, thisProjectRef) map { ( pid, sbtDep, classifiers, lb, ref) =>
 			val pluginIDs: Seq[ModuleID] = lb.units(ref.build).unit.plugins.fullClasspath.flatMap(_ get moduleID.key)
@@ -1006,10 +1003,10 @@ object Classpaths
 
 	def projectDependenciesTask: Initialize[Task[Seq[ModuleID]]] =
 		(thisProjectRef, settings, buildDependencies) map { (ref, data, deps) =>
-			deps.classpath(ref) flatMap { dep => (projectID in dep.project) get data map { 
+			deps.classpath(ref) flatMap { dep => (projectID in dep.project) get data map {
 				_.copy(configurations = dep.configuration, explicitArtifacts = Nil) } 
 			}
-		}
+	}
 
 	def depMap: Initialize[Task[Map[ModuleRevisionId, ModuleDescriptor]]] =
 		(thisProjectRef, settings, buildDependencies, streams) flatMap { (root, data, deps, s) =>
@@ -1179,8 +1176,9 @@ object Classpaths
 	}
 
 	lazy val compilerPluginConfig = Seq(
-		scalacOptions <<= (scalacOptions, autoCompilerPlugins, update) map { (options, auto, report) =>
-			if(auto) options ++ autoPlugins(report) else options
+		scalacOptions := {
+			val options = scalacOptions.value
+			if(autoCompilerPlugins.value) options ++ autoPlugins(update.value) else options
 		}
 	)
 	def substituteScalaFiles(scalaInstance: ScalaInstance, report: UpdateReport): UpdateReport =
@@ -1264,16 +1262,16 @@ trait BuildExtra extends BuildCommon
 
 	def addArtifact(a: Artifact, taskDef: TaskKey[File]): SettingsDefinition =
 	{
-		val pkgd = packagedArtifacts <<= (packagedArtifacts, taskDef) map ( (pas,file) => pas updated (a, file) )
+		val pkgd = packagedArtifacts := packagedArtifacts.value updated (a, taskDef.value)
 		seq( artifacts += a, pkgd )
 	}
 	def addArtifact(artifact: Initialize[Artifact], taskDef: Initialize[Task[File]]): SettingsDefinition =
 	{
 		val artLocal = SettingKey.local[Artifact]
 		val taskLocal = TaskKey.local[File]
-		val art = artifacts <<= (artLocal, artifacts)( _ +: _ )
-		val pkgd = packagedArtifacts <<= (packagedArtifacts, artLocal, taskLocal) map ( (pas,a,file) => pas updated (a, file))
-		seq( artLocal <<= artifact, taskLocal <<= taskDef, art, pkgd )
+		val art = artifacts := artLocal.value +: artifacts.value
+		val pkgd = packagedArtifacts := packagedArtifacts.value updated (artLocal.value, taskLocal.value)
+		seq( artLocal := artifact.value, taskLocal := taskDef.value, art, pkgd )
 	}
 
 	def seq(settings: Setting[_]*): SettingsDefinition = new Def.SettingList(settings)
diff --git a/main/EvaluateConfigurations.scala b/main/EvaluateConfigurations.scala
index 8160f0a7c..87ba3570b 100644
--- a/main/EvaluateConfigurations.scala
+++ b/main/EvaluateConfigurations.scala
@@ -52,7 +52,10 @@ object EvaluateConfigurations
 	def addOffsetToRange(offset: Int, ranges: Seq[(String,LineRange)]): Seq[(String,LineRange)] =
 		ranges.map { case (s, r) => (s, r shift offset) }
 
-	val SettingsDefinitionName = classOf[SettingsDefinition].getName
+	val SettingsDefinitionName = {
+		val _ = classOf[SettingsDefinition] // this line exists to try to provide a compile-time error when the following line needs to be changed
+		"sbt.Def.SettingsDefinition"
+	}
 	def evaluateSetting(eval: Eval, name: String, imports: Seq[(String,Int)], expression: String, range: LineRange): ClassLoader => Seq[Setting[_]] =
 	{
 		val result = try {
diff --git a/main/Keys.scala b/main/Keys.scala
index fb26359d0..2dc9861f5 100644
--- a/main/Keys.scala
+++ b/main/Keys.scala
@@ -320,7 +320,7 @@ object Keys
 	val tags = SettingKey[Seq[(Tags.Tag,Int)]]("tags", ConcurrentRestrictions.tagsKey.label, BSetting)
 	val concurrentRestrictions = SettingKey[Seq[Tags.Rule]]("concurrent-restrictions", "Rules describing restrictions on concurrent task execution.", BSetting)
 	val cancelable = SettingKey[Boolean]("cancelable", "Enables (true) or disables (false) the ability to interrupt task execution with CTRL+C.", BMinusSetting)
-	val settingsData = TaskKey[Settings[Scope]]("settings-data", "Provides access to the project data for the build.", DTask)
+	val settingsData = std.FullInstance.settingsData
 	@deprecated("Use Keys.settingsData.", "0.12.0")
 	val settings = settingsData
 	val streams = TaskKey[TaskStreams]("streams", "Provides streams for logging and persisting data.", DTask)
diff --git a/main/Project.scala b/main/Project.scala
index 8ff6c0796..523aacb26 100755
--- a/main/Project.scala
+++ b/main/Project.scala
@@ -72,6 +72,12 @@ final case class ClasspathDependency(project: ProjectReference, configuration: O
 
 object Project extends ProjectExtra
 {
+	@deprecated("Use Def.Setting", "0.13.0")
+	type Setting[T] = Def.Setting[T]
+
+	@deprecated("Use Def.Initialize", "0.13.0")
+	type Initialize[T] = Def.Initialize[T]
+
 	def showContextKey(state: State): Show[ScopedKey[_]] =
 		showContextKey(state, None)
 
diff --git a/main/settings/Def.scala b/main/settings/Def.scala
index cd4d5a50e..7895e5017 100644
--- a/main/settings/Def.scala
+++ b/main/settings/Def.scala
@@ -2,6 +2,7 @@ package sbt
 
 	import java.io.File
 
+/** A concrete settings system that uses `sbt.Scope` for the scope type. */
 object Def extends Init[Scope]
 {
 	type Classpath = Seq[Attributed[File]]
@@ -9,7 +10,6 @@ object Def extends Init[Scope]
 	val triggeredBy = AttributeKey[Seq[Task[_]]]("triggered-by")
 	val runBefore = AttributeKey[Seq[Task[_]]]("run-before")
 	private[sbt] val parseResult: TaskKey[Any] = TaskKey("$parse-result", "Internal: used to implement input tasks.", KeyRanks.Invisible)
-	// TODO: move back to Keys
 	val resolvedScoped = SettingKey[ScopedKey[_]]("resolved-scoped", "The ScopedKey for the referencing setting or task.", KeyRanks.DSetting)
 
 	lazy val showFullKey: Show[ScopedKey[_]] = showFullKey(None)
@@ -34,4 +34,16 @@ object Def extends Init[Scope]
 		case Some(c) => c + s + scala.Console.RESET
 		case None => s
 	}
+
+	/** Lifts the result of a setting initialization into a Task. */
+	def toITask[T](i: Initialize[T]): Initialize[Task[T]] = map(i)(std.TaskExtra.inlineTask)
+
+	// The following conversions enable the types Initialize[T], Initialize[Task[T]], and Task[T] to
+	//  be used in task and setting macros as inputs with an ultimate result of type T
+
+		import language.experimental.macros
+		import std.TaskMacro.MacroValue
+	implicit def macroValueI[T](in: Initialize[T]): MacroValue[T] = ???
+	implicit def macroValueIT[T](in: Initialize[Task[T]]): MacroValue[T] = ???
+	implicit def macroValueT[T](in: Task[T]): MacroValue[T] = ???
 }
\ No newline at end of file
diff --git a/main/settings/SettingMacro.scala b/main/settings/SettingMacro.scala
new file mode 100644
index 000000000..875c3e4c9
--- /dev/null
+++ b/main/settings/SettingMacro.scala
@@ -0,0 +1,43 @@
+package sbt
+package std
+
+	import Def.{Initialize,Setting}
+	import Types.{idFun,Id}
+	import appmacro.{Convert, Instance, MixedBuilder, MonadInstance}
+
+object InitializeInstance extends MonadInstance
+{
+	type M[x] = Initialize[x]
+	def app[K[L[x]], Z](in: K[Initialize], f: K[Id] => Z)(implicit a: AList[K]): Initialize[Z] = Def.app[K,Z](in)(f)(a)
+	def map[S,T](in: Initialize[S], f: S => T): Initialize[T] = Def.map(in)(f)
+	def flatten[T](in: Initialize[Initialize[T]]): Initialize[T] = Def.bind(in)(idFun[Initialize[T]])
+	def pure[T](t: () => T): Initialize[T] = Def.pure(t)
+}
+object InitializeConvert extends Convert
+{
+	def apply[T: c.TypeTag](c: reflect.makro.Context)(in: c.Tree): c.Tree =
+		if(in.tpe <:< c.typeOf[Initialize[Task[T]]] || in.tpe <:< c.typeOf[Task[T]])
+			c.abort(in.pos, "A setting cannot depend on a task")
+		else if(in.tpe <:< c.typeOf[Initialize[T]])
+		{
+			val i = c.Expr[Initialize[T]](in)
+			c.universe.reify( i.splice ).tree
+		}
+		else
+			c.abort(in.pos, "Unknown input type: " + in.tpe)
+}
+
+	import language.experimental.macros
+	import scala.reflect._
+	import makro._
+
+object SettingMacro
+{
+	def setting[T](t: T): Initialize[T] = macro settingMacroImpl[T]
+	def settingMacroImpl[T: c.TypeTag](c: Context)(t: c.Expr[T]): c.Expr[Initialize[T]] =
+		Instance.contImpl[T](c, InitializeInstance, InitializeConvert, MixedBuilder)(Left(t))
+
+	def settingDyn[T](t: Initialize[T]): Initialize[T] = macro settingDynMacroImpl[T]
+	def settingDynMacroImpl[T: c.TypeTag](c: Context)(t: c.Expr[Initialize[T]]): c.Expr[Initialize[T]] = 
+		Instance.contImpl[T](c, InitializeInstance, InitializeConvert, MixedBuilder)(Right(t))
+}
diff --git a/main/settings/Structure.scala b/main/settings/Structure.scala
index 6ff75c035..66aa07fd5 100644
--- a/main/settings/Structure.scala
+++ b/main/settings/Structure.scala
@@ -15,6 +15,8 @@ package sbt
 	import Task._
 	import Types._
 
+	import language.experimental.macros
+
 sealed trait Scoped { def scope: Scope; val key: AttributeKey[_] }
 
 /** A common type for SettingKey and TaskKey so that both can be used as inputs to tasks.*/
@@ -26,13 +28,18 @@ sealed trait ScopedTaskable[T] extends Scoped {
 * The scope is represented by a value of type Scope.
 * The name and the type are represented by a value of type AttributeKey[T].
 * Instances are constructed using the companion object. */
-sealed trait SettingKey[T] extends ScopedTaskable[T] with KeyedInitialize[T] with Scoped.ScopingSetting[SettingKey[T]] with Scoped.DefinableSetting[T] with Scoped.ListSetting[T, Id]
+sealed trait SettingKey[T] extends ScopedTaskable[T] with KeyedInitialize[T] with Scoped.ScopingSetting[SettingKey[T]] with Scoped.DefinableSetting[T]
 {
 	val key: AttributeKey[T]
 	def toTask: Initialize[Task[T]] = this apply inlineTask
 	def scopedKey: ScopedKey[T] = ScopedKey(scope, key)
 	def in(scope: Scope): SettingKey[T] = Scoped.scopedSetting(Scope.replaceThis(this.scope)(scope), this.key)
 
+	def +=[U](v: U)(implicit a: Append.Value[T, U]): Setting[T]  =  macro std.TaskMacro.settingAppend1Impl[T,U]
+	def ++=[U](vs: U)(implicit a: Append.Values[T, U]): Setting[T]  =  macro std.TaskMacro.settingAppendNImpl[T,U]
+	def <+= [V](value: Initialize[V])(implicit a: Append.Value[T, V]): Setting[T]  =  make(value)(a.appendValue)
+	def <++= [V](values: Initialize[V])(implicit a: Append.Values[T, V]): Setting[T]  =  make(values)(a.appendValues)
+
 	protected[this] def make[S](other: Initialize[S])(f: (T, S) => T): Setting[T] = this <<= (this, other)(f)
 }
 
@@ -40,14 +47,19 @@ sealed trait SettingKey[T] extends ScopedTaskable[T] with KeyedInitialize[T] wit
 * The scope is represented by a value of type Scope.
 * The name and the type are represented by a value of type AttributeKey[Task[T]].
 * Instances are constructed using the companion object. */
-sealed trait TaskKey[T] extends ScopedTaskable[T] with KeyedInitialize[Task[T]] with Scoped.ScopingSetting[TaskKey[T]] with Scoped.ListSetting[T, Task] with Scoped.DefinableTask[T]
+sealed trait TaskKey[T] extends ScopedTaskable[T] with KeyedInitialize[Task[T]] with Scoped.ScopingSetting[TaskKey[T]] with Scoped.DefinableTask[T]
 {
 	val key: AttributeKey[Task[T]]
 	def toTask: Initialize[Task[T]] = this
 	def scopedKey: ScopedKey[Task[T]] = ScopedKey(scope, key)
 	def in(scope: Scope): TaskKey[T] = Scoped.scopedTask(Scope.replaceThis(this.scope)(scope), this.key)
 
-	protected[this] def make[S](other: Initialize[Task[S]])(f: (T, S) => T): Setting[Task[T]] = this <<= (this, other) { (a,b) => (a,b) map f.tupled }
+	def +=[U](v: U)(implicit a: Append.Value[T, U]): Setting[Task[T]]  =  macro std.TaskMacro.taskAppend1Impl[T,U]
+	def ++=[U](vs: U)(implicit a: Append.Values[T, U]): Setting[Task[T]]  =  macro std.TaskMacro.taskAppendNImpl[T,U]
+	def <+= [V](v: Initialize[Task[V]])(implicit a: Append.Value[T, V]): Setting[Task[T]]  =  make(v)(a.appendValue)
+	def <++= [V](vs: Initialize[Task[V]])(implicit a: Append.Values[T, V]): Setting[Task[T]]  =  make(vs)(a.appendValues)
+
+	private[this] def make[S](other: Initialize[Task[S]])(f: (T, S) => T): Setting[Task[T]] = this <<= (this, other) { (a,b) => (a,b) map f.tupled }
 }
 
 /** Identifies an input task.  An input task parses input and produces a task to run.
@@ -86,24 +98,15 @@ object Scoped
 	def scopedInput[T](s: Scope, k: AttributeKey[InputTask[T]]): InputKey[T]  =  new InputKey[T] { val scope = s; val key = k }
 	def scopedTask[T](s: Scope, k: AttributeKey[Task[T]]): TaskKey[T]  =  new TaskKey[T] { val scope = s; val key = k }
 
-	sealed trait ListSetting[S, M[_]]
-	{
-		protected[this] def make[T](other: Initialize[M[T]])(f: (S, T) => S): Setting[M[S]]
-		protected[this] def ~=(f: S => S): Setting[M[S]]
-
-		def <+= [V](value: Initialize[M[V]])(implicit a: Append.Value[S, V]): Setting[M[S]]  =  make(value)(a.appendValue)
-		def <++= [V](values: Initialize[M[V]])(implicit a: Append.Values[S, V]): Setting[M[S]]  =  make(values)(a.appendValues)
-		def += [U](value: => U)(implicit a: Append.Value[S, U]): Setting[M[S]]  =  this ~= ( v => a.appendValue(v, value) )
-		def ++=[U](values: => U)(implicit a: Append.Values[S, U]): Setting[M[S]]  =  this ~= ( v => a.appendValues(v, values) )
-	}
 	sealed trait DefinableSetting[S]
 	{
 		def scopedKey: ScopedKey[S]
 
-		private[sbt] final def :==(value: S): Setting[S]  =  :=(value)
-		final def := (value: => S): Setting[S]  =  setting(scopedKey, Def.value(value))
+		private[sbt] final def :==(value: S): Setting[S]  =  setting(scopedKey, Def.valueStrict(value))
+		final def := (v: S): Setting[S]  =  macro std.TaskMacro.settingAssignMacroImpl[S]
 		final def ~= (f: S => S): Setting[S]  =  Def.update(scopedKey)(f)
-		final def <<= (app: Initialize[S]): Setting[S]  =  setting(scopedKey, app)
+		final def <<= (app: Initialize[S]): Setting[S]  =  set(app)
+		final def set (app: Initialize[S]): Setting[S]  =  setting(scopedKey, app)
 		final def get(settings: Settings[Scope]): Option[S] = settings.get(scopedKey.scope, scopedKey.key)
 		final def ? : Initialize[Option[S]] = Def.optional(scopedKey)(idFun)
 		final def or[T >: S](i: Initialize[T]): Initialize[T] = (this.?, i)(_ getOrElse _ )
@@ -111,28 +114,24 @@ object Scoped
 	}
 	final class RichInitialize[S](init: Initialize[S])
 	{
-		@deprecated("A call to 'identity' is no longer necessary and can be removed.", "0.11.0")
-		final def identity: Initialize[S] = init
 		def map[T](f: S => T): Initialize[Task[T]] = init(s => mktask(f(s)) )
 		def flatMap[T](f: S => Task[T]): Initialize[Task[T]] = init(f)
 	}
 	sealed trait DefinableTask[S]
 	{ self: TaskKey[S] =>
 
-		private[sbt] def :==(value: S): Setting[Task[S]]  =  :=(value)
-		private[sbt] def ::=(value: Task[S]): Setting[Task[S]]  =  Def.setting(scopedKey, Def.value( value ))
-		def := (value: => S): Setting[Task[S]]  =  ::=(mktask(value))
+		private[sbt] def :==(v: S): Setting[Task[S]]  =  ::=(constant(v))
+		private[sbt] def ::=(value: Task[S]): Setting[Task[S]]  =  Def.setting(scopedKey, Def.valueStrict( value ))
+		def := (v: S): Setting[Task[S]]  =  macro std.TaskMacro.taskAssignMacroImpl[S] //::=(mktask(value))
 		private[sbt] def :== (v: SettingKey[S]): Setting[Task[S]] = <<=( v(constant))
 		def ~= (f: S => S): Setting[Task[S]]  =  Def.update(scopedKey)( _ map f )
 
-		def <<= (app: Initialize[Task[S]]): Setting[Task[S]]  =  Def.setting(scopedKey, app)
+		def <<= (app: Initialize[Task[S]]): Setting[Task[S]]  =  set(app)
+		def set(app: Initialize[Task[S]]): Setting[Task[S]]  =  Def.setting(scopedKey, app)
 
 		def task: SettingKey[Task[S]] = scopedSetting(scope, key)
 		def get(settings: Settings[Scope]): Option[Task[S]] = settings.get(scope, key)
 
-		@deprecated("A call to 'identity' is no longer necessary and can be removed.", "0.11.0")
-		def identity: Initialize[Task[S]] = this
-
 		def ? : Initialize[Task[Option[S]]] = Def.optional(scopedKey) { case None => mktask { None }; case Some(t) => t map some.fn }
 		def ??[T >: S](or: => T): Initialize[Task[T]] = Def.optional(scopedKey)( _ getOrElse mktask(or) )
 		def or[T >: S](i: Initialize[Task[T]]): Initialize[Task[T]] = (this.? zipWith i)( (x,y) => (x, y) map { case (a,b) => a getOrElse b})
@@ -246,7 +245,6 @@ object Scoped
 		def flatFailure[T](f: Seq[Incomplete] => Task[T]): App[T] = onTasks(_ flatFailure f)
 		def mapFailure[T](f: Seq[Incomplete] => T): App[T] = onTasks(_ mapFailure f)
 	}
-	type :@:[H, T <: KList[ScopedTaskable]] = KCons[H, T, ScopedTaskable]
 	type ST[X] = ScopedTaskable[X]
 	final class RichTaskable2[A,B](t2: (ST[A], ST[B])) extends RichTaskables[ AList.T2K[A,B]#l ](t2)(AList.tuple2[A,B])
 	{
diff --git a/main/settings/TaskMacro.scala b/main/settings/TaskMacro.scala
new file mode 100644
index 000000000..52539ea91
--- /dev/null
+++ b/main/settings/TaskMacro.scala
@@ -0,0 +1,185 @@
+package sbt
+package std
+
+	import Def.{Initialize,Setting}
+	import Types.{idFun,Id}
+	import TaskExtra.allM
+	import appmacro.{Convert, InputWrapper, Instance, MixedBuilder, MonadInstance}
+
+	import language.experimental.macros
+	import scala.reflect._
+	import makro._
+
+/** Instance for the monad/applicative functor for plain Tasks. */
+object TaskInstance extends MonadInstance
+{
+	import TaskExtra._
+
+	final type M[x] = Task[x]
+	def app[K[L[x]], Z](in: K[Task], f: K[Id] => Z)(implicit a: AList[K]): Task[Z] = new Mapped[Z,K](in, f compose allM, a)
+	def map[S,T](in: Task[S], f: S => T): Task[T] = in map f
+	def flatten[T](in: Task[Task[T]]): Task[T] = in flatMap idFun[Task[T]]
+	def pure[T](t: () => T): Task[T] = toTask(t)
+}
+
+/** Composes the Task and Initialize Instances to provide an Instance for [T] Initialize[Task[T]].*/
+object FullInstance extends Instance.Composed[Initialize, Task](InitializeInstance, TaskInstance) with MonadInstance
+{
+	type SS = sbt.Settings[Scope]
+	val settingsData = TaskKey[SS]("settings-data", "Provides access to the project data for the build.", KeyRanks.DTask)
+
+	def flatten[T](in: Initialize[Task[Initialize[Task[T]]]]): Initialize[Task[T]] =
+	{
+			import Scoped._
+		(in,settingsData) apply{
+			(a: Task[Initialize[Task[T]]], data: Task[SS]) =>
+				import TaskExtra.multT2Task
+				(a, data) flatMap { case (a,d) => a evaluate d }
+		}
+	}
+}
+/** Converts an input `Tree` of type `Initialize[T]`, `Initialize[Task[T]]`, or `Task[T]` into a `Tree` of type `Initialize[Task[T]]`.*/
+object FullConvert extends Convert
+{
+	def apply[T: c.TypeTag](c: Context)(in: c.Tree): c.Tree =
+		if(in.tpe <:< c.typeOf[Initialize[Task[T]]])
+			in
+		else if(in.tpe <:< c.typeOf[Initialize[T]])
+		{
+			val i = c.Expr[Initialize[T]](in)
+			c.universe.reify( Def.toITask(i.splice) ).tree
+		}
+		else if(in.tpe <:< c.typeOf[Task[T]])
+		{
+			val i = c.Expr[Task[T]](in)
+			c.universe.reify( Def.valueStrict[Task[T]](i.splice) ).tree
+		}
+		else
+			c.abort(in.pos, "Unknown input type: " + in.tpe)
+}
+
+object TaskMacro
+{
+	final val AssignInitName = "<<="
+	final val Append1InitName = "<+="
+	final val AppendNInitName = "<++="
+
+	def task[T](t: T): Initialize[Task[T]] = macro taskMacroImpl[T]
+	def taskMacroImpl[T: c.TypeTag](c: Context)(t: c.Expr[T]): c.Expr[Initialize[Task[T]]] = 
+		Instance.contImpl[T](c, FullInstance, FullConvert, MixedBuilder)(Left(t))
+
+	def taskDyn[T](t: Initialize[Task[T]]): Initialize[Task[T]] = macro taskDynMacroImpl[T]
+	def taskDynMacroImpl[T: c.TypeTag](c: Context)(t: c.Expr[Initialize[Task[T]]]): c.Expr[Initialize[Task[T]]] = 
+		Instance.contImpl[T](c, FullInstance, FullConvert, MixedBuilder)(Right(t))
+
+	/** Implementation of := macro for settings. */
+	def settingAssignMacroImpl[T: c.TypeTag](c: Context)(v: c.Expr[T]): c.Expr[Setting[T]] =
+	{
+		val init = SettingMacro.settingMacroImpl[T](c)(v)
+		val assign = transformMacroImpl(c)( init.tree )( AssignInitName )
+		c.Expr[Setting[T]]( assign )
+	}
+	/** Implementation of := macro for tasks. */
+	def taskAssignMacroImpl[T: c.TypeTag](c: Context)(v: c.Expr[T]): c.Expr[Setting[Task[T]]] =
+	{
+		val init = taskMacroImpl[T](c)(v)
+		val assign = transformMacroImpl(c)( init.tree )( AssignInitName )
+		c.Expr[Setting[Task[T]]]( assign )
+	}
+	/** Implementation of += macro for tasks. */
+	def taskAppend1Impl[T: c.TypeTag, U: c.TypeTag](c: Context)(v: c.Expr[U])(a: c.Expr[Append.Value[T, U]]): c.Expr[Setting[Task[T]]] =
+	{
+		val init = taskMacroImpl[U](c)(v)
+		val assign = appendMacroImpl(c)( init.tree, a.tree )( Append1InitName )
+		c.Expr[Setting[Task[T]]]( assign )
+	}
+	/** Implementation of += macro for settings. */
+	def settingAppend1Impl[T: c.TypeTag, U: c.TypeTag](c: Context)(v: c.Expr[U])(a: c.Expr[Append.Value[T, U]]): c.Expr[Setting[T]] =
+	{
+		val init = SettingMacro.settingMacroImpl[U](c)(v)
+		val assign = appendMacroImpl(c)( init.tree, a.tree )( Append1InitName )
+		c.Expr[Setting[T]]( assign )
+	}
+	/** Implementation of ++= macro for tasks. */
+	def taskAppendNImpl[T: c.TypeTag, U: c.TypeTag](c: Context)(vs: c.Expr[U])(a: c.Expr[Append.Values[T, U]]): c.Expr[Setting[Task[T]]] =
+	{
+		val init = taskMacroImpl[U](c)(vs)
+		val assign = appendMacroImpl(c)( init.tree, a.tree )( AppendNInitName )
+		c.Expr[Setting[Task[T]]]( assign )
+	}
+	/** Implementation of ++= macro for settings. */
+	def settingAppendNImpl[T: c.TypeTag, U: c.TypeTag](c: Context)(vs: c.Expr[U])(a: c.Expr[Append.Values[T, U]]): c.Expr[Setting[T]] =
+	{
+		val init = SettingMacro.settingMacroImpl[U](c)(vs)
+		val assign = appendMacroImpl(c)( init.tree, a.tree )( AppendNInitName )
+		c.Expr[Setting[T]]( assign )
+	}
+
+	private[this] def appendMacroImpl(c: Context)(init: c.Tree, append: c.Tree)(newName: String): c.Tree =
+	{
+			import c.universe.{Apply,newTermName,Select,TypeApply}
+		c.macroApplication match {
+			case Apply(Apply(TypeApply(Select(preT, nmeT), targs), _), a) =>	
+				Apply(Apply(TypeApply(Select(preT, newTermName(newName).encodedName), targs), init :: Nil), a)
+			case x => unexpectedTree(x)
+		}
+	}
+	private[this] def transformMacroImpl(c: Context)(init: c.Tree)(newName: String): c.Tree =
+	{
+			import c.universe.{Apply,newTermName,Select}
+		val target = 
+			c.macroApplication match {
+				case Apply(Select(prefix, _), _) => prefix
+				case x => unexpectedTree(x)
+			}
+		Apply.apply(Select(target, newTermName(newName).encodedName), init :: Nil)
+	}
+	private[this] def unexpectedTree[C <: Context](tree: C#Tree): Nothing = error("Unexpected macro application tree (" + tree.getClass + "): " + tree)
+
+	sealed abstract class MacroValue[T] {
+		def value: T = macro std.TaskMacro.valueMacroImpl[T]
+	}
+
+	def valueMacroImpl[T: c.TypeTag](c: Context): c.Expr[T] =
+	{
+			import c.universe._
+		c.macroApplication match {
+			case Select(Apply(_, t :: Nil), _) => wrap[T](c)(t, implicitly[c.TypeTag[T]])
+			case x => unexpectedTree(x)
+		}
+	}
+	private[this] def wrap[T](c: Context)(t: c.Tree, tag: c.TypeTag[T]): c.Expr[T] =
+	{
+		val rc = c.asInstanceOf[scala.reflect.makro.runtime.Context]
+		val tree = rc.universe.TypeTree().setType(tag.tpe.asInstanceOf[rc.universe.Type])
+		val cleaned = rc.callsiteTyper.packedType(tree, rc.universe.NoSymbol).asInstanceOf[c.universe.Type]
+		implicit val t1 = c.TypeTag[T](cleaned)
+		val ts = c.Expr[Any](t)
+		c.universe.reify { InputWrapper.wrap[T](ts.splice) }
+	}
+}
+
+/** Convert instance for plain `Task`s not within the settings system.
+* This is not used for the main task/setting macros, but could be used when manipulating plain Tasks.*/
+object TaskConvert extends Convert
+{
+	def apply[T: c.TypeTag](c: Context)(in: c.Tree): c.Tree =
+		if(in.tpe <:< c.typeOf[Task[T]])
+		{
+			val i = c.Expr[Task[T]](in)
+			c.universe.reify( i.splice ).tree
+		}
+		else
+			c.abort(in.pos, "Unknown input type: " + in.tpe)
+}
+
+object PlainTaskMacro
+{
+	def task[T](t: T): Task[T] = macro taskImpl[T]
+	def taskImpl[T: c.TypeTag](c: Context)(t: c.Expr[T]): c.Expr[Task[T]] = 
+		Instance.contImpl[T](c, TaskInstance, TaskConvert, MixedBuilder)(Left(t))
+
+	def taskDyn[T](t: Task[T]): Task[T] = macro taskDynImpl[T]
+	def taskDynImpl[T: c.TypeTag](c: Context)(t: c.Expr[Task[T]]): c.Expr[Task[T]] = 
+		Instance.contImpl[T](c, TaskInstance, TaskConvert, MixedBuilder)(Right(t))
+}
diff --git a/main/settings/src/test/scala/UsageTest.scala b/main/settings/src/test/scala/UsageTest.scala
new file mode 100644
index 000000000..ed05480d3
--- /dev/null
+++ b/main/settings/src/test/scala/UsageTest.scala
@@ -0,0 +1,38 @@
+package sbt
+package std
+
+object UseTask
+{
+		import Def._
+		import TaskMacro.{task, taskDyn}
+
+	val set = SettingMacro setting { 23 }
+	val plain = PlainTaskMacro task { 19 }
+
+	val x = task { set.value }
+	val y = task { true }
+	val z = task { if(y.value) x.value else plain.value }
+	val a = taskDyn { 
+		if(y.value) z else x
+	}
+}
+object Assign
+{
+	import java.io.File
+	import Def.macroValueT
+	import UseTask.{x,y,z,a,set,plain}
+
+	val ak = TaskKey[Int]("a")
+	val bk = TaskKey[Seq[Int]]("b")
+	val ck = SettingKey[File]("c")
+	val sk = TaskKey[Set[_]]("s")
+
+	def azy = sk.value
+
+	val settings = Seq(
+		ak += z.value + (if(y.value) set.value else plain.value),
+		bk ++= Seq(z.value),
+		ck := new File(ck.value, "asdf"),
+		ak := sk.value.size + sk.value.size
+	)
+}
\ No newline at end of file
diff --git a/project/Sbt.scala b/project/Sbt.scala
index 65481f3ef..37ff6b541 100644
--- a/project/Sbt.scala
+++ b/project/Sbt.scala
@@ -16,7 +16,7 @@ object Sbt extends Build
 		organization := "org.scala-sbt",
 		version := "0.13.0-SNAPSHOT",
 		publishArtifact in packageDoc := false,
-		scalaVersion := "2.10.0-M5",
+		scalaVersion := "2.10.0-M6",
 		publishMavenStyle := false,
 		componentID := None,
 		crossPaths := false,
@@ -53,6 +53,7 @@ object Sbt extends Build
 
 	lazy val controlSub = baseProject(utilPath / "control", "Control")
 	lazy val collectionSub = testedBaseProject(utilPath / "collection", "Collections") settings( Util.keywordsSettings: _* )
+	lazy val applyMacroSub = testedBaseProject(utilPath / "appmacro", "Apply Macro") dependsOn(collectionSub) settings(scalaCompiler)
 		// The API for forking, combining, and doing I/O with system processes
 	lazy val processSub = baseProject(utilPath / "process", "Process") dependsOn(ioSub % "test->test")
 		// Path, IO (formerly FileUtilities), NameFilter and other I/O utility classes
@@ -121,13 +122,13 @@ object Sbt extends Build
 		interfaceSub, ioSub, ivySub, logSub, processSub, runSub, relationSub, stdTaskSub, taskSub, trackingSub, testingSub)
 
 		// General command support and core commands not specific to a build system
-	lazy val commandSub = testedBaseProject(commandPath, "Command") dependsOn(interfaceSub, ioSub, launchInterfaceSub, logSub, completeSub, classpathSub)
+	lazy val commandSub = testedBaseProject(mainPath / "command", "Command") dependsOn(interfaceSub, ioSub, launchInterfaceSub, logSub, completeSub, classpathSub)
 		// Fixes scope=Scope for Setting (core defined in collectionSub) to define the settings system used in build definitions
-	lazy val settingsSub = testedBaseProject(settingsPath, "Settings") dependsOn(interfaceSub, ivySub, relationSub, logSub, ioSub, commandSub, completeSub,
-		classpathSub, stdTaskSub, processSub) settings( sbinary )
+	lazy val mainSettingsSub = testedBaseProject(mainPath / "settings", "Main Settings") dependsOn(applyMacroSub, interfaceSub, ivySub, relationSub, logSub, ioSub, commandSub,
+		completeSub, classpathSub, stdTaskSub, processSub) settings( sbinary )
 
 		// The main integration project for sbt.  It brings all of the subsystems together, configures them, and provides for overriding conventions.
-	lazy val mainSub = testedBaseProject(mainPath, "Main") dependsOn(actionsSub, settingsSub, interfaceSub, ioSub, ivySub, launchInterfaceSub, logSub, processSub, runSub, commandSub)
+	lazy val mainSub = testedBaseProject(mainPath, "Main") dependsOn(actionsSub, mainSettingsSub, interfaceSub, ioSub, ivySub, launchInterfaceSub, logSub, processSub, runSub, commandSub)
 
 		// Strictly for bringing implicits and aliases from subsystems into the top-level sbt namespace through a single package object
 		//  technically, we need a dependency on all of mainSub's dependencies, but we don't do that since this is strictly an integration project
@@ -142,8 +143,6 @@ object Sbt extends Build
 	def utilPath = file("util")
 	def compilePath = file("compile")
 	def mainPath = file("main")
-	def commandPath = mainPath / "command"
-	def settingsPath = mainPath / "settings"
 	def scriptedPath = file("scripted")
 
 	def sbtSettings = Seq(
diff --git a/sbt/src/sbt-test/project/flatten/project/Flat.scala b/sbt/src/sbt-test/project/flatten/project/Flat.scala
index 7d46ee4e4..032624155 100644
--- a/sbt/src/sbt-test/project/flatten/project/Flat.scala
+++ b/sbt/src/sbt-test/project/flatten/project/Flat.scala
@@ -17,12 +17,10 @@ object Flat extends Build
 	def forConfig(conf: Configuration, name: String) = Project.inConfig(conf)( unpackageSettings(name) )
 
 	def unpackageSettings(name: String) = Seq(
-		unmanagedSourceDirectories <<= baseDirectory( base => (base / name) :: Nil ),
-		defaultExcludes in unmanagedResources <<= sourceFilter.identity,
-		unmanagedResourceDirectories <<= unmanagedSourceDirectories.identity,
-		unpackage <<= (artifactPath in packageSrc, baseDirectory) map { (jar, base) =>
-			IO.unzip(jar, base / name)
-		}
+		unmanagedSourceDirectories := (baseDirectory.value / name) :: Nil,
+		defaultExcludes in unmanagedResources := sourceFilter.value,
+		unmanagedResourceDirectories := unmanagedSourceDirectories.value,
+		unpackage := IO.unzip(artifactPath in packageSrc value, baseDirectory.value / name)
 	)
 
 	val unpackage = TaskKey[Unit]("unpackage")
diff --git a/util/appmacro/ContextUtil.scala b/util/appmacro/ContextUtil.scala
new file mode 100644
index 000000000..31f61c356
--- /dev/null
+++ b/util/appmacro/ContextUtil.scala
@@ -0,0 +1,104 @@
+package sbt
+package appmacro
+
+	import scala.reflect._
+	import makro._
+	import scala.tools.nsc.Global
+
+object ContextUtil {
+	/** Constructs an object with utility methods for operating in the provided macro context `c`.
+	* Callers should explicitly specify the type parameter as `c.type` in order to preserve the path dependent types. */
+	def apply[C <: Context with Singleton](c: C): ContextUtil[C] = new ContextUtil(c)
+}
+
+/** Utility methods for macros.  Several methods assume that the context's universe is a full compiler (`scala.tools.nsc.Global`).
+* This is not thread safe due to the underlying Context and related data structures not being thread safe.
+* Use `ContextUtil[c.type](c)` to construct. */
+final class ContextUtil[C <: Context with Singleton](val ctx: C) 
+{
+		import ctx.universe.{Apply=>ApplyTree,_}
+
+	val alistType = ctx.typeOf[AList[KList]]
+	val alist: Symbol = alistType.typeSymbol.companionSymbol
+	val alistTC: Type = alistType.typeConstructor
+
+	/** Modifiers for a local val.*/
+	val localModifiers = Modifiers(NoFlags)
+
+	def getPos(sym: Symbol) = if(sym eq null) NoPosition else sym.pos
+
+	/** Constructs a unique term name with the given prefix within this Context.
+	* (The current implementation uses Context.fresh, which increments*/
+	def freshTermName(prefix: String) = newTermName(ctx.fresh("$" + prefix))
+
+	def typeTree(tpe: Type) = TypeTree().setType(tpe)
+
+	/** Constructs a new, local ValDef with the given Type, a unique name, 
+	* the same position as `sym`, and an empty implementation (no rhs). */
+	def freshValDef(tpe: Type, sym: Symbol): ValDef =
+	{
+		val vd = localValDef(typeTree(tpe), EmptyTree)
+		vd setPos getPos(sym)
+		vd
+	}
+
+	/** Constructs a ValDef with local modifiers and a unique name. */
+	def localValDef(tpt: Tree, rhs: Tree): ValDef =
+		ValDef(localModifiers, freshTermName("q"), tpt, rhs)
+
+	/** Constructs a tuple value of the right TupleN type from the provided inputs.*/
+	def mkTuple(args: List[Tree]): Tree =
+	{
+		val global: Global = ctx.universe.asInstanceOf[Global]
+		global.gen.mkTuple(args.asInstanceOf[List[global.Tree]]).asInstanceOf[ctx.universe.Tree]
+	}
+
+	/** Creates a new, synthetic type variable with the specified `owner`. */
+	def newTypeVariable(owner: Symbol): Symbol =
+	{
+		val global: Global = ctx.universe.asInstanceOf[Global]
+		owner.asInstanceOf[global.Symbol].newSyntheticTypeParam().asInstanceOf[ctx.universe.Symbol]
+	}
+	/** The type representing the type constructor `[X] X` */
+	val idTC: Type =
+	{
+		val tvar = newTypeVariable(NoSymbol)
+		polyType(tvar :: Nil, refVar(tvar))
+	}
+	/** Constructs a new, synthetic type variable that is a type constructor. For example, in type Y[L[x]], L is such a type variable. */
+	def newTCVariable(owner: Symbol): Symbol =
+	{
+		val global: Global = ctx.universe.asInstanceOf[Global]
+		val tc = owner.asInstanceOf[global.Symbol].newSyntheticTypeParam()
+		val arg = tc.newSyntheticTypeParam("x", 0L)
+		tc.setInfo(global.PolyType(arg :: Nil, global.TypeBounds.empty)).asInstanceOf[ctx.universe.Symbol]
+	}
+	/** Returns the Symbol that references the statically accessible singleton `i`. */
+	def singleton[T <: AnyRef with Singleton](i: T)(implicit it: ctx.TypeTag[i.type]): Symbol =
+		it.tpe match {
+			case SingleType(_, sym) if !sym.isFreeTerm && sym.isStatic => sym
+			case x => error("Instance must be static (was " + x + ").")
+		}
+	/** Constructs a Type that references the given type variable. */
+	def refVar(variable: Symbol): Type = typeRef(NoPrefix, variable, Nil)
+
+	/** Returns the symbol for the non-private method named `name` for the class/module `obj`. */
+	def method(obj: Symbol, name: String): Symbol = {
+		val global: Global = ctx.universe.asInstanceOf[Global]
+		obj.asInstanceOf[global.Symbol].info.nonPrivateMember(global.newTermName(name)).asInstanceOf[ctx.universe.Symbol]
+	}
+
+	/** Returns a Type representing the type constructor tcp.<name>.  For example, given
+	*  `object Demo { type M[x] = List[x] }`, the call `extractTC(Demo, "M")` will return a type representing
+	* the type constructor `[x] List[x]`.
+	**/
+	def extractTC(tcp: AnyRef with Singleton, name: String)(implicit it: ctx.TypeTag[tcp.type]): ctx.Type =
+	{
+		val global: Global = ctx.universe.asInstanceOf[Global]
+		val itTpe = it.tpe.asInstanceOf[global.Type]
+		val m = itTpe.nonPrivateMember(global.newTypeName(name))
+		val tc = itTpe.memberInfo(m).asInstanceOf[ctx.universe.Type]
+		assert(tc != NoType && tc.isHigherKinded, "Invalid type constructor: " + tc)
+		tc
+	}
+}
\ No newline at end of file
diff --git a/util/appmacro/Instance.scala b/util/appmacro/Instance.scala
new file mode 100644
index 000000000..05a80b4e8
--- /dev/null
+++ b/util/appmacro/Instance.scala
@@ -0,0 +1,260 @@
+package sbt
+package appmacro
+
+	import Classes.Applicative
+	import Types.Id
+
+/** The separate hierarchy from Applicative/Monad is for two reasons.
+*
+* 1. The type constructor is represented as an abstract type because a TypeTag cannot represent a type constructor directly.
+* 2. The applicative interface is uncurried.
+*/
+trait Instance
+{
+	type M[x]
+	def app[K[L[x]], Z](in: K[M], f: K[Id] => Z)(implicit a: AList[K]): M[Z]
+	def map[S,T](in: M[S], f: S => T): M[T]
+	def pure[T](t: () => T): M[T]
+}
+trait Convert
+{
+	def apply[T: c.TypeTag](c: scala.reflect.makro.Context)(in: c.Tree): c.Tree
+}
+trait MonadInstance extends Instance
+{
+	def flatten[T](in: M[M[T]]): M[T]
+}
+object InputWrapper
+{
+	def wrap[T](in: Any): T = error("This method is an implementation detail and should not be referenced.")
+}
+
+	import scala.reflect._
+	import makro._
+
+object Instance
+{
+	final val DynamicDependencyError = "Illegal dynamic dependency."
+	final val DynamicReferenceError = "Illegal dynamic reference."
+	final val ApplyName = "app"
+	final val FlattenName = "flatten"
+	final val PureName = "pure"
+	final val MapName = "map"
+	final val InstanceTCName = "M"
+	final val WrapName = "wrap"
+
+	final class Input[U <: Universe with Singleton](val tpe: U#Type, val expr: U#Tree, val local: U#ValDef)
+
+	/** Implementation of a macro that provides a direct syntax for applicative functors and monads.
+	* It is intended to be used in conjunction with another macro that conditions the inputs.
+	*
+	* This method processes the Tree `t` to find inputs of the form `InputWrapper.wrap[T]( input )`
+	* This form is typically constructed by another macro that pretends to be able to get a value of type `T`
+	* from a value convertible to `M[T]`.  This `wrap(input)` form has two main purposes.
+	* First, it identifies the inputs that should be transformed.
+	* Second, it allows the input trees to be wrapped for later conversion into the appropriate `M[T]` type by `convert`.
+	* This wrapping is necessary because applying the first macro must preserve the original type,
+	* but it is useful to delay conversion until the outer, second macro is called.  The `wrap` method accomplishes this by
+	* allowing the original `Tree` and `Type` to be hidden behind the raw `T` type.  This method will remove the call to `wrap`
+	* so that it is not actually called at runtime.
+	*
+	* Each `input` in each expression of the form `InputWrapper.wrap[T]( input )` is transformed by `convert`.
+	* This transformation converts the input Tree to a Tree of type `M[T]`.
+	* The original wrapped expression `wrap(input)` is replaced by a reference to a new local `val $x: T`, where `$x` is a fresh name.
+	* These converted inputs are passed to `builder` as well as the list of these synthetic `ValDef`s.
+	* The `TupleBuilder` instance constructs a tuple (Tree) from the inputs and defines the right hand side of the vals
+	* that unpacks the tuple containing the results of the inputs.
+	* 
+	* The constructed tuple of inputs and the code that unpacks the results of the inputs are then passed to the `i`,
+	* which is an implementation of `Instance` that is statically accessible.
+	* An Instance defines a applicative functor associated with a specific type constructor and, if it implements MonadInstance as well, a monad.
+	* Typically, it will be either a top-level module or a stable member of a top-level module (such as a val or a nested module).
+	* The `with Singleton` part of the type verifies some cases at macro compilation time,
+	*  while the full check for static accessibility is done at macro expansion time.
+	* Note: Ideally, the types would verify that `i: MonadInstance` when `t.isRight`.
+	* With the various dependent types involved, this is not worth it.
+	* 
+	* The `t` argument is the argument of the macro that will be transformed as described above.
+	* If the macro that calls this method is for a multi-input map (app followed by map),
+	* `t` should be the argument wrapped in Left.
+	* If this is for multi-input flatMap (app followed by flatMap), 
+	*  this should be the argument wrapped in Right.
+	*/
+	def contImpl[T: c.TypeTag](c: Context, i: Instance with Singleton, convert: Convert, builder: TupleBuilder)(t: Either[c.Expr[T], c.Expr[i.M[T]]])(
+		implicit tt: c.TypeTag[T], mt: c.TypeTag[i.M[T]], it: c.TypeTag[i.type]): c.Expr[i.M[T]] =
+	{
+			import c.universe.{Apply=>ApplyTree,_}
+
+			import scala.tools.nsc.Global
+			// Used to access compiler methods not yet exposed via the reflection/macro APIs
+		val global: Global = c.universe.asInstanceOf[Global]
+		
+		val util = ContextUtil[c.type](c)
+		val mTC: Type = util.extractTC(i, InstanceTCName)
+
+		// the tree for the macro argument
+		val (tree, treeType) = t match {
+			case Left(l) => (l.tree, tt.tpe.normalize)
+			case Right(r) => (r.tree, mt.tpe.normalize)
+		}
+
+		val instanceSym = util.singleton(i)
+		// A Tree that references the statically accessible Instance that provides the actual implementations of map, flatMap, ... 
+		val instance = Ident(instanceSym)
+
+		val parameterModifiers = Modifiers(Flag.PARAM)
+
+		val wrapperSym = util.singleton(InputWrapper)
+		val wrapMethodSymbol = util.method(wrapperSym, WrapName)
+		def isWrapper(fun: Tree) = fun.symbol == wrapMethodSymbol
+
+		type In = Input[c.universe.type]
+		var inputs = List[In]()
+
+		// constructs a ValDef with a parameter modifier, a unique name, with the provided Type and with an empty rhs
+		def freshMethodParameter(tpe: Type): ValDef =
+			ValDef(parameterModifiers, freshTermName("p"), typeTree(tpe), EmptyTree)
+
+		def freshTermName(prefix: String) = newTermName(c.fresh("$" + prefix))
+		def typeTree(tpe: Type) = TypeTree().setType(tpe)
+
+		// constructs a function that applies f to each subtree of the input tree
+		def visitor(f: Tree => Unit): Tree => Unit =
+		{
+			val v: Transformer = new Transformer {
+				override def transform(tree: Tree): Tree = { f(tree); super.transform(tree) }
+			}
+			(tree: Tree) => v.transform(tree)
+		}
+
+		/* Local definitions in the macro.  This is used to ensure
+		* references are to M instances defined outside of the macro call.*/
+		val defs = new collection.mutable.HashSet[Symbol]
+
+		// a reference is illegal if it is to an M instance defined within the scope of the macro call
+		def illegalReference(sym: Symbol): Boolean =
+			sym != null && sym != NoSymbol && defs.contains(sym)
+
+		// a function that checks the provided tree for illegal references to M instances defined in the
+		//  expression passed to the macro and for illegal dereferencing of M instances.
+		val checkQual = visitor {
+			case s @ ApplyTree(fun, qual :: Nil) => if(isWrapper(fun)) c.error(s.pos, DynamicDependencyError)
+			case id @ Ident(name) if illegalReference(id.symbol) => c.error(id.pos, DynamicReferenceError)
+			case _ => ()
+		}
+		// adds the symbols for all non-Ident subtrees to `defs`.
+		val defSearch = visitor {
+			case _: Ident => ()
+			case tree => if(tree.symbol ne null) defs += tree.symbol; 
+		}
+
+		// transforms the original tree into calls to the Instance functions pure, map, ...,
+		//  resulting in a value of type M[T]
+		def makeApp(body: Tree): Tree =
+			inputs match {
+				case Nil => pure(body)
+				case x :: Nil => single(body, x)
+				case xs => arbArity(body, xs)
+			}
+
+		// no inputs, so construct M[T] via Instance.pure or pure+flatten
+		def pure(body: Tree): Tree =
+		{
+			val typeApplied = TypeApply(Select(instance, PureName), typeTree(treeType) :: Nil)
+			val p = ApplyTree(typeApplied, Function(Nil, body) :: Nil)
+			if(t.isLeft) p else flatten(p)
+		}
+		// m should have type M[M[T]]
+		// the returned Tree will have type M[T]
+		def flatten(m: Tree): Tree =
+		{
+			val typedFlatten = TypeApply(Select(instance, FlattenName), typeTree(tt.tpe) :: Nil)
+			ApplyTree(typedFlatten, m :: Nil)
+		}
+
+		// calls Instance.map or flatmap directly, skipping the intermediate Instance.app that is unnecessary for a single input
+		def single(body: Tree, input: In): Tree =
+		{
+			val variable = input.local
+			val param = ValDef(parameterModifiers, variable.name, variable.tpt, EmptyTree)
+			val typeApplied = TypeApply(Select(instance, MapName), variable.tpt :: typeTree(treeType) :: Nil)
+			val mapped = ApplyTree(typeApplied, input.expr :: Function(param :: Nil, body) :: Nil)
+			if(t.isLeft) mapped else flatten(mapped)
+		}
+
+		// calls Instance.app to get the values for all inputs and then calls Instance.map or flatMap to evaluate the body
+		def arbArity(body: Tree, inputs: List[In]): Tree =
+		{
+			val result = builder.make(c)(mTC, inputs)
+			val param = freshMethodParameter( appliedType(result.representationC, util.idTC :: Nil) )
+			val bindings = result.extract(param)
+			val f = Function(param :: Nil, Block(bindings, body))
+			val ttt = typeTree(treeType)
+			val typedApp = TypeApply(Select(instance, ApplyName), typeTree(result.representationC) :: ttt :: Nil)
+			val app = ApplyTree(ApplyTree(typedApp, result.input :: f :: Nil), result.alistInstance :: Nil)
+			if(t.isLeft) app else flatten(app)
+		}
+
+		// called when transforming the tree to add an input
+		//  for `qual` of type M[A], and a selection qual.value,
+		//  the call is addType(Type A, Tree qual)
+		// the result is a Tree representing a reference to
+		//  the bound value of the input
+		def addType(tpe: Type, qual: Tree): Tree =
+		{
+			checkQual(qual)
+			val vd = util.freshValDef(tpe, qual.symbol)
+			inputs ::= new Input(tpe, qual, vd)
+			Ident(vd.name)
+		}
+
+		// the main tree transformer that replaces calls to InputWrapper.wrap(x) with
+		//  plain Idents that reference the actual input value
+		object appTransformer extends Transformer
+		{
+			override def transform(tree: Tree): Tree =
+				tree match
+				{
+					case ApplyTree(TypeApply(fun, t :: Nil), qual :: Nil) if isWrapper(fun) =>
+						val tag = c.TypeTag(t.tpe)
+						addType(t.tpe, convert(c)(qual)(tag) )
+					case _ => super.transform(tree)
+				}
+		}
+
+		// collects all definitions in the tree.  used for finding illegal references
+		defSearch(tree)
+
+		// applies the transformation
+		//   resetting attributes: a) must be local b) must be done
+		//   on the transformed tree and not the wrapped tree or else there are obscure errors
+		val tr = makeApp( c.resetLocalAttrs(appTransformer.transform(tree)) )
+		c.Expr[i.M[T]](tr)
+	}
+
+		import Types._
+
+	implicit def applicativeInstance[A[_]](implicit ap: Applicative[A]): Instance { type M[x] = A[x] } = new Instance
+	{
+		type M[x] = A[x]
+		def app[ K[L[x]], Z ](in: K[A], f: K[Id] => Z)(implicit a: AList[K]) = a.apply[A,Z](in, f)
+		def map[S,T](in: A[S], f: S => T) = ap.map(f, in)
+		def pure[S](s: () => S): M[S] = ap.pure(s())
+	}
+
+	type AI[A[_]] = Instance { type M[x] = A[x] }
+	def compose[A[_], B[_]](implicit a: AI[A], b: AI[B]): Instance { type M[x] = A[B[x]] } = new Composed[A,B](a,b)
+	// made a public, named, unsealed class because of trouble with macros and inference when the Instance is not an object
+	class Composed[A[_], B[_]](a: AI[A], b: AI[B]) extends Instance
+	{
+		type M[x] = A[B[x]]
+		def pure[S](s: () => S): A[B[S]] = a.pure(() => b.pure(s))
+		def map[S,T](in: M[S], f: S => T): M[T] = a.map(in, (bv: B[S]) => b.map(bv, f))
+		def app[ K[L[x]], Z ](in: K[M], f: K[Id] => Z)(implicit alist: AList[K]): A[B[Z]] =
+		{
+			val g: K[B] => B[Z] = in => b.app[K, Z](in, f)
+			type Split[ L[x] ] = K[ (L ∙ B)#l ]
+			a.app[Split, B[Z]](in, g)(AList.asplit(alist))
+		}
+	}
+}
diff --git a/util/appmacro/KListBuilder.scala b/util/appmacro/KListBuilder.scala
new file mode 100644
index 000000000..5b658ea69
--- /dev/null
+++ b/util/appmacro/KListBuilder.scala
@@ -0,0 +1,58 @@
+package sbt
+package appmacro
+
+	import Types.Id
+	import scala.tools.nsc.Global
+	import scala.reflect._
+	import makro._
+
+/** A `TupleBuilder` that uses a KList as the tuple representation.*/
+object KListBuilder extends TupleBuilder
+{
+	def make(c: Context)(mt: c.Type, inputs: Inputs[c.universe.type]): BuilderResult[c.type] = new BuilderResult[c.type]
+	{
+		val ctx: c.type = c
+		val util = ContextUtil[c.type](c)
+			import c.universe.{Apply=>ApplyTree,_}
+			import util._
+
+		val knilType = c.typeOf[KNil]
+		val knil = Ident(knilType.typeSymbol.companionSymbol)
+		val kconsTpe = c.typeOf[KCons[Int,KNil,List]]
+		val kcons = kconsTpe.typeSymbol.companionSymbol
+		val mTC: Type = mt.asInstanceOf[c.universe.Type]
+		val kconsTC: Type = kconsTpe.typeConstructor
+
+		/** This is the L in the type function [L[x]] ...  */
+		val tcVariable: Symbol = newTCVariable(NoSymbol)
+
+		/** Instantiates KCons[h, t <: KList[L], L], where L is the type constructor variable */
+		def kconsType(h: Type, t: Type): Type =
+			appliedType(kconsTC, h :: t :: refVar(tcVariable) :: Nil)
+
+		def bindKList(prev: ValDef, revBindings: List[ValDef], params: List[ValDef]): List[ValDef] =
+			params match
+			{
+				case ValDef(mods, name, tpt, _) :: xs =>
+					val head = ValDef(mods, name, tpt, Select(Ident(prev.name), "head"))
+					val tail = localValDef(TypeTree(), Select(Ident(prev.name), "tail"))
+					val base = head :: revBindings
+					bindKList(tail, if(xs.isEmpty) base else tail :: base, xs)
+				case Nil => revBindings.reverse
+			}
+
+		/** The input trees combined in a KList */
+		val klist = (inputs :\ (knil: Tree))( (in, klist) => ApplyTree(kcons, in.expr, klist) )
+
+		/** The input types combined in a KList type.  The main concern is tracking the heterogeneous types.
+		* The type constructor is tcVariable, so that it can be applied to [X] X or M later.  
+		* When applied to `M`, this type gives the type of the `input` KList. */
+		val klistType: Type = (inputs :\ knilType)( (in, klist) => kconsType(in.tpe, klist) )
+
+		val representationC = PolyType(tcVariable :: Nil, klistType)
+		val resultType = appliedType(representationC, idTC :: Nil)
+		val input = klist
+		val alistInstance = TypeApply(Select(Ident(alist), "klist"), typeTree(representationC) :: Nil)
+		def extract(param: ValDef) = bindKList(param, Nil, inputs.map(_.local))
+	}
+}
\ No newline at end of file
diff --git a/util/appmacro/MixedBuilder.scala b/util/appmacro/MixedBuilder.scala
new file mode 100644
index 000000000..593f60382
--- /dev/null
+++ b/util/appmacro/MixedBuilder.scala
@@ -0,0 +1,16 @@
+package sbt
+package appmacro
+
+	import scala.reflect._
+	import makro._
+
+/** A builder that uses `TupleN` as the representation for small numbers of inputs (up to `TupleNBuilder.MaxInputs`) 
+* and `KList` for larger numbers of inputs. This builder cannot handle fewer than 2 inputs.*/
+object MixedBuilder extends TupleBuilder
+{
+	def make(c: Context)(mt: c.Type, inputs: Inputs[c.universe.type]): BuilderResult[c.type] =
+	{
+		val delegate = if(inputs.size > TupleNBuilder.MaxInputs) KListBuilder else TupleNBuilder
+		delegate.make(c)(mt, inputs)
+	}
+}
\ No newline at end of file
diff --git a/util/appmacro/TupleBuilder.scala b/util/appmacro/TupleBuilder.scala
new file mode 100644
index 000000000..f91d3c91c
--- /dev/null
+++ b/util/appmacro/TupleBuilder.scala
@@ -0,0 +1,56 @@
+package sbt
+package appmacro
+
+	import Types.Id
+	import scala.tools.nsc.Global
+	import scala.reflect._
+	import makro._
+
+/** 
+* A `TupleBuilder` abstracts the work of constructing a tuple data structure such as a `TupleN` or `KList`
+* and extracting values from it.  The `Instance` macro implementation will (roughly) traverse the tree of its argument
+* and ultimately obtain a list of expressions with type `M[T]` for different types `T`.
+* The macro constructs an `Input` value for each of these expressions that contains the `Type` for `T`,
+* the `Tree` for the expression, and a `ValDef` that will hold the value for the input.
+*
+* `TupleBuilder.apply` is provided with the list of `Input`s and is expected to provide three values in the returned BuilderResult.
+* First, it returns the constructed tuple data structure Tree in `input`.
+* Next, it provides the type constructor `representationC` that, when applied to M, gives the type of tuple data structure.
+* For example, a builder that constructs a `Tuple3` for inputs `M[Int]`, `M[Boolean]`, and `M[String]`
+* would provide a Type representing `[L[x]] (L[Int], L[Boolean], L[String])`.  The `input` method
+* would return a value whose type is that type constructor applied to M, or `(M[Int], M[Boolean], M[String])`.
+*
+* Finally, the `extract` method provides a list of vals that extract information from the applied input.
+* The type of the applied input is the type constructor applied to `Id` (`[X] X`).
+* The returned list of ValDefs should be the ValDefs from `inputs`, but with non-empty right-hand sides.
+*/
+trait TupleBuilder {
+	/** A convenience alias for a list of inputs (associated with a Universe of type U). */
+	type Inputs[U <: Universe with Singleton] = List[Instance.Input[U]]
+
+	/** Constructs a one-time use Builder for Context `c` and type constructor `tcType`. */
+	def make(c: Context)(tcType: c.Type, inputs: Inputs[c.universe.type]): BuilderResult[c.type]
+}
+
+trait BuilderResult[C <: Context with Singleton]
+{
+	val ctx: C
+	import ctx.universe._
+
+	/** Represents the higher-order type constructor `[L[x]] ...` where `...` is the
+	* type of the data structure containing the added expressions,
+	* except that it is abstracted over the type constructor applied to each heterogeneous part of the type . */
+	def representationC: PolyType
+
+	/** The instance of AList for the input.  For a `representationC` of `[L[x]]`, this `Tree` should have a `Type` of `AList[L]`*/
+	def alistInstance: Tree
+
+	/** Returns the completed value containing all expressions added to the builder. */
+	def input: Tree
+
+	/* The list of definitions that extract values from a value of type `$representationC[Id]`.
+	* The returned value should be identical to the `ValDef`s provided to the `TupleBuilder.make` method but with
+	* non-empty right hand sides. Each `ValDef` may refer to `param` and previous `ValDef`s in the list.*/
+	def extract(param: ValDef): List[ValDef]
+}
+
diff --git a/util/appmacro/TupleNBuilder.scala b/util/appmacro/TupleNBuilder.scala
new file mode 100644
index 000000000..ddf312f1b
--- /dev/null
+++ b/util/appmacro/TupleNBuilder.scala
@@ -0,0 +1,51 @@
+package sbt
+package appmacro
+
+	import Types.Id
+	import scala.tools.nsc.Global
+	import scala.reflect._
+	import makro._
+
+/** A builder that uses a TupleN as the tuple representation.
+* It is limited to tuples of size 2 to `MaxInputs`. */
+object TupleNBuilder extends TupleBuilder
+{
+	/** The largest number of inputs that this builder can handle. */
+	final val MaxInputs = 11
+	final val TupleMethodName = "tuple"
+
+	def make(c: Context)(mt: c.Type, inputs: Inputs[c.universe.type]): BuilderResult[c.type] = new BuilderResult[c.type]
+	{
+		val util = ContextUtil[c.type](c)
+			import c.universe.{Apply=>ApplyTree,_}
+			import util._
+
+		val global: Global = c.universe.asInstanceOf[Global]
+		val mTC: Type = mt.asInstanceOf[c.universe.Type]
+
+		val ctx: c.type = c
+		val representationC: PolyType = {
+			val tcVariable: Symbol = newTCVariable(NoSymbol)
+			val tupleTypeArgs = inputs.map(in => typeRef(NoPrefix, tcVariable, in.tpe :: Nil).asInstanceOf[global.Type])
+			val tuple = global.definitions.tupleType(tupleTypeArgs)
+			PolyType(tcVariable :: Nil, tuple.asInstanceOf[Type] )
+		}
+		val resultType = appliedType(representationC, idTC :: Nil)
+
+		val input: Tree = mkTuple(inputs.map(_.expr))
+		val alistInstance: Tree = {
+			val select = Select(Ident(alist), TupleMethodName + inputs.size.toString)
+			TypeApply(select, inputs.map(in => typeTree(in.tpe)))
+		}
+		def extract(param: ValDef): List[ValDef] = bindTuple(param, Nil, inputs.map(_.local), 1)
+
+		def bindTuple(param: ValDef, revBindings: List[ValDef], params: List[ValDef], i: Int): List[ValDef] =
+			params match
+			{
+				case ValDef(mods, name, tpt, _) :: xs =>
+					val x = ValDef(mods, name, tpt, Select(Ident(param.name), "_" + i.toString))
+					bindTuple(param, x :: revBindings, xs, i+1)
+				case Nil => revBindings.reverse
+			}
+	}
+}
diff --git a/util/collection/AList.scala b/util/collection/AList.scala
index 212a58411..6e5946318 100644
--- a/util/collection/AList.scala
+++ b/util/collection/AList.scala
@@ -3,8 +3,9 @@ package sbt
 	import Classes.Applicative
 	import Types._
 
-/** An abstraction over (* -> *) -> * with the purpose of abstracting over arity abstractions like KList and TupleN
-* as well as homogeneous sequences Seq[M[T]]. */
+/** An abstraction over a higher-order type constructor `K[x[y]]` with the purpose of abstracting
+* over heterogeneous sequences like `KList` and `TupleN` with elements with a common type
+* constructor as well as homogeneous sequences `Seq[M[T]]`. */
 trait AList[K[L[x]] ]
 {
 	def transform[M[_], N[_]](value: K[M], f: M ~> N): K[N]
@@ -18,6 +19,7 @@ trait AList[K[L[x]] ]
 object AList
 {
 	type Empty = AList[({ type l[L[x]] = Unit})#l]
+	/** AList for Unit, which represents a sequence that is always empty.*/
 	val empty: Empty = new Empty {
 		def transform[M[_], N[_]](in: Unit, f: M ~> N) = ()
 		def foldr[M[_], T](in: Unit, f: (M[_], T) => T, init: T) = init
@@ -26,6 +28,7 @@ object AList
 	}
 
 	type SeqList[T] = AList[({ type l[L[x]] = List[L[T]] })#l]
+	/** AList for a homogeneous sequence. */
 	def seq[T]: SeqList[T] = new SeqList[T]
 	{
 		def transform[M[_], N[_]](s: List[M[T]], f: M ~> N) = s.map(f.fn[T])
@@ -44,6 +47,7 @@ object AList
 		def traverse[M[_], N[_], P[_]](s: List[M[T]], f: M ~> (N ∙ P)#l)(implicit np: Applicative[N]): N[List[P[T]]] = ???
 	}
 
+	/** AList for the abitrary arity data structure KList. */
 	def klist[KL[M[_]] <: KList[M] { type Transform[N[_]] = KL[N] }]: AList[KL] = new AList[KL] {
 		def transform[M[_], N[_]](k: KL[M], f: M ~> N) = k.transform(f)
 		def foldr[M[_], T](k: KL[M], f: (M[_], T) => T, init: T): T = k.foldr(f, init)
@@ -51,6 +55,7 @@ object AList
 		def traverse[M[_], N[_], P[_]](k: KL[M], f: M ~> (N ∙ P)#l)(implicit np: Applicative[N]): N[KL[P]] = k.traverse[N,P](f)(np)
 	}
 
+	/** AList for a single value. */
 	type Single[A] = AList[({ type l[L[x]] = L[A]})#l]
 	def single[A]: Single[A] = new Single[A] {
 		def transform[M[_], N[_]](a: M[A], f: M ~> N) = f(a)
@@ -58,8 +63,8 @@ object AList
 		def traverse[M[_], N[_], P[_]](a: M[A], f: M ~> (N ∙ P)#l)(implicit np: Applicative[N]): N[P[A]] = f(a)
 	}
 
-
    type ASplit[K[L[x]], B[x]] = AList[ ({ type l[L[x]] = K[ (L ∙ B)#l] })#l ]
+	/** AList that operates on the outer type constructor `A` of a composition `[x] A[B[x]]` for type constructors `A` and `B`*/
    def asplit[ K[L[x]], B[x] ](base: AList[K]): ASplit[K,B] = new ASplit[K, B]
    {
       type Split[ L[x] ] = K[ (L ∙ B)#l ]
diff --git a/util/collection/KList.scala b/util/collection/KList.scala
index 70e3852f9..7ecc6ba6a 100644
--- a/util/collection/KList.scala
+++ b/util/collection/KList.scala
@@ -11,9 +11,16 @@ sealed trait KList[+M[_]]
 	/** Apply the natural transformation `f` to each element. */
 	def transform[N[_]](f: M ~> N): Transform[N]
 
+	/** Folds this list using a function that operates on the homogeneous type of the elements of this list. */
 	def foldr[T](f: (M[_], T) => T, init: T): T = init // had trouble defining it in KNil
+
+	/** Applies `f` to the elements of this list in the applicative functor defined by `ap`. */
 	def apply[N[x] >: M[x], Z](f: Transform[Id] => Z)(implicit ap: Applicative[N]): N[Z]
+
+	/** Equivalent to `transform(f) . apply(x => x)`, this is the essence of the iterator at the level of natural transformations.*/
 	def traverse[N[_], P[_]](f: M ~> (N ∙ P)#l)(implicit np: Applicative[N]): N[Transform[P]]
+
+	/** Discards the heterogeneous type information and constructs a plain List from this KList's elements. */
 	def toList: List[M[_]]
 }
 final case class KCons[H, +T <: KList[M], +M[_]](head: M[H], tail: T) extends KList[M]
diff --git a/util/collection/Settings.scala b/util/collection/Settings.scala
index 981096c0b..783956f2a 100644
--- a/util/collection/Settings.scala
+++ b/util/collection/Settings.scala
@@ -59,7 +59,9 @@ trait Init[Scope]
 	type MapConstant = ScopedKey ~> Option
 
 	def setting[T](key: ScopedKey[T], init: Initialize[T], pos: SourcePosition = NoPosition): Setting[T] = new Setting[T](key, init, pos)
-	def value[T](value: => T): Initialize[T] = new Value(value _)
+	def valueStrict[T](value: T): Initialize[T] = pure(() => value)
+	def value[T](value: => T): Initialize[T] = pure(value _)
+	def pure[T](value: () => T): Initialize[T] = new Value(value)
 	def optional[T,U](i: Initialize[T])(f: Option[T] => U): Initialize[U] = new Optional(Some(i), f)
 	def update[T](key: ScopedKey[T])(f: T => T): Setting[T] = new Setting[T](key, map(key)(f), NoPosition)
 	def bind[S,T](in: Initialize[S])(f: S => Initialize[T]): Initialize[T] = new Bind(f, in)