diff --git a/src/main/scala/scala/tools/partest/PartestTask.scala b/src/main/scala/scala/tools/partest/PartestTask.scala
index 269fa11..dd255b8 100644
--- a/src/main/scala/scala/tools/partest/PartestTask.scala
+++ b/src/main/scala/scala/tools/partest/PartestTask.scala
@@ -118,9 +118,7 @@ class PartestTask extends Task with CompilationPathProperty with ScalaTask {
   }
 
   override def execute() {
-    if (debug || propOrFalse("partest.debug")) {
-      NestUI.setDebug()
-    }
+    val nestUI: NestUI = new NestUI(debug = debug || propOrFalse("partest.debug"))
 
     if (compilationPath.isEmpty) sys.error("Mandatory attribute 'compilationPath' is not set.")
 
@@ -130,7 +128,7 @@ class PartestTask extends Task with CompilationPathProperty with ScalaTask {
     })
 
     var failureCount = 0
-    val summary = new scala.tools.partest.nest.AntRunner(srcDir.getOrElse(null), new URLClassLoader(compilationPath.get.list.map(Path(_).toURL)), javacmd.getOrElse(null), javaccmd.getOrElse(null), scalacArgsFlat, javaOpts) {
+    val summary = new scala.tools.partest.nest.AntRunner(srcDir.getOrElse(null), new URLClassLoader(compilationPath.get.list.map(Path(_).toURL)), javacmd.getOrElse(null), javaccmd.getOrElse(null), scalacArgsFlat, javaOpts, nestUI) {
       def echo(msg: String): Unit = PartestTask.this.log(msg)
       def log(msg: String): Unit = PartestTask.this.log(msg)
 
diff --git a/src/main/scala/scala/tools/partest/nest/AbstractRunner.scala b/src/main/scala/scala/tools/partest/nest/AbstractRunner.scala
index d26413c..8981868 100644
--- a/src/main/scala/scala/tools/partest/nest/AbstractRunner.scala
+++ b/src/main/scala/scala/tools/partest/nest/AbstractRunner.scala
@@ -12,31 +12,47 @@ import scala.tools.nsc.Properties.{ versionMsg, propOrFalse, setProp }
 import scala.collection.{ mutable, immutable }
 import TestKinds._
 import scala.reflect.internal.util.Collections.distinctBy
-import scala.tools.cmd.{ CommandLine, CommandLineParser, Instance }
 
-abstract class AbstractRunner(argstr: String) extends {
-  val parsed = RunnerSpec.creator(CommandLineParser tokenize argstr)
-} with RunnerSpec with Instance {
+abstract class AbstractRunner {
+
+  val config: RunnerSpec.Config
+
+  lazy val nestUI: NestUI = new NestUI(
+    verbose = config.optVerbose,
+    debug = config.optDebug || propOrFalse("partest.debug"),
+    terse = config.optTerse,
+    diffOnFail = config.optShowDiff,
+    logOnFail = config.optShowLog,
+    colorEnabled = colorEnabled
+  )
 
   val suiteRunner: SuiteRunner
 
-  import suiteRunner._
-  import NestUI._
-  import NestUI.color._
+  protected val printSummary         = true
+  protected val partestCmd           = "test/partest"
+  protected val colorEnabled         = sys.props contains "partest.colors"
+
+  private[this] var totalTests       = 0
+  private[this] val passedTests      = mutable.ListBuffer[TestState]()
+  private[this] val failedTests      = mutable.ListBuffer[TestState]()
+
+  private[this] var summarizing      = false
+  private[this] var elapsedMillis    = 0L
+  private[this] var expectedFailures = 0
 
-  private var totalTests  = 0
-  private val passedTests = mutable.ListBuffer[TestState]()
-  private val failedTests = mutable.ListBuffer[TestState]()
+  import nestUI._
+  import nestUI.color._
 
-  def comment(s: String) = echo(magenta("# " + s))
-  def levyJudgment() = {
+  private[this] def comment(s: String) = echo(magenta("# " + s))
+
+  private[this] def levyJudgment() = {
     if (totalTests == 0) echoMixed("No tests to run.")
     else if (elapsedMillis == 0) echoMixed("Test Run ABORTED")
     else if (isSuccess) echoPassed("Test Run PASSED")
     else echoFailed("Test Run FAILED")
   }
 
-  def passFailString(passed: Int, failed: Int, skipped: Int): String = {
+  private[this] def passFailString(passed: Int, failed: Int, skipped: Int): String = {
     val total = passed + failed + skipped
     val isSuccess = failed == 0
     def p0 = s"$passed/$total"
@@ -47,12 +63,7 @@ abstract class AbstractRunner(argstr: String) extends {
     oempty(p, f, s) mkString ", "
   }
 
-  protected var partestCmd       = "test/partest"
-  protected var summarizing      = false
-  protected var printSummary     = true
-  private var elapsedMillis    = 0L
-  private var expectedFailures = 0
-  protected def isSuccess = failedTests.size == expectedFailures
+  private[this] def isSuccess = failedTests.size == expectedFailures
 
   def issueSummaryReport() {
     // Don't run twice
@@ -69,7 +80,7 @@ abstract class AbstractRunner(argstr: String) extends {
       val message   = passFail + elapsed
 
       if (failed0.nonEmpty) {
-        if (isPartestVerbose) {
+        if (nestUI.verbose) {
           echo(bold(cyan("##### Transcripts from failed tests #####\n")))
           failed0 foreach { state =>
             comment(partestCmd + " " + state.testFile)
@@ -89,97 +100,93 @@ abstract class AbstractRunner(argstr: String) extends {
     }
   }
 
-  def run(): Unit = {
-    if (optDebug || propOrFalse("partest.debug")) NestUI.setDebug()
-    if (optVerbose)  NestUI.setVerbose()
-    if (optTerse)    NestUI.setTerse()
-    if (optShowDiff) NestUI.setDiffOnFail()
-    if (optShowLog)  NestUI.setLogOnFail()
-
-    // Early return on no args, version, or invalid args
-    if (optVersion) return echo(versionMsg)
-    if (optHelp) return NestUI.usage()
-
-    val (individualTests, invalid) = parsed.residualArgs map (p => Path(p)) partition denotesTestPath
-    if (invalid.nonEmpty) {
-      if (isPartestVerbose)
-        invalid foreach (p => echoWarning(s"Discarding invalid test path " + p))
-      else if (!isPartestTerse)
-        echoWarning(s"Discarding ${invalid.size} invalid test paths")
-    }
+  /** Run the tests and return the success status */
+  def run(): Boolean = {
+    if (config.optVersion) echo(versionMsg)
+    else if (config.optHelp) nestUI.usage()
+    else {
+      val (individualTests, invalid) = config.parsed.residualArgs map (p => Path(p)) partition denotesTestPath
+      if (invalid.nonEmpty) {
+        if (nestUI.verbose)
+          invalid foreach (p => echoWarning(s"Discarding invalid test path " + p))
+        else if (!nestUI.terse)
+          echoWarning(s"Discarding ${invalid.size} invalid test paths")
+      }
 
-    optTimeout foreach (x => setProp("partest.timeout", x))
+      config.optTimeout foreach (x => setProp("partest.timeout", x))
 
-    if (!isPartestTerse)
-      NestUI echo banner
+      if (!nestUI.terse)
+        nestUI.echo(suiteRunner.banner)
 
-    val partestTests = (
-      if (optSelfTest) TestKinds.testsForPartest
-      else Nil
-    )
+      val partestTests = (
+        if (config.optSelfTest) TestKinds.testsForPartest
+        else Nil
+      )
 
-    val grepExpr = optGrep getOrElse ""
+      val grepExpr = config.optGrep getOrElse ""
 
-    // If --grep is given we suck in every file it matches.
-    // TODO: intersect results of grep with specified kinds, if any
-    val greppedTests = if (grepExpr == "") Nil else {
-      val paths = grepFor(grepExpr)
-      if (paths.isEmpty)
-        echoWarning(s"grep string '$grepExpr' matched no tests.\n")
+      // If --grep is given we suck in every file it matches.
+      // TODO: intersect results of grep with specified kinds, if any
+      val greppedTests = if (grepExpr == "") Nil else {
+        val paths = grepFor(grepExpr)
+        if (paths.isEmpty)
+          echoWarning(s"grep string '$grepExpr' matched no tests.\n")
 
-      paths.sortBy(_.toString)
-    }
+        paths.sortBy(_.toString)
+      }
 
-    val isRerun = optFailed
-    val rerunTests = if (isRerun) TestKinds.failedTests else Nil
-    def miscTests = partestTests ++ individualTests ++ greppedTests ++ rerunTests
-
-    val givenKinds = standardKinds filter parsed.isSet
-    val kinds = (
-      if (givenKinds.nonEmpty) givenKinds
-      else if (miscTests.isEmpty) standardKinds // If no kinds, --grep, or individual tests were given, assume --all
-      else Nil
-    )
-    val kindsTests = kinds flatMap testsFor
-
-    def testContributors = {
-      List(
-        if (partestTests.isEmpty) "" else "partest self-tests",
-        if (rerunTests.isEmpty) "" else "previously failed tests",
-        if (kindsTests.isEmpty) "" else s"${kinds.size} named test categories",
-        if (greppedTests.isEmpty) "" else s"${greppedTests.size} tests matching '$grepExpr'",
-        if (individualTests.isEmpty) "" else "specified tests"
-      ) filterNot (_ == "") mkString ", "
-    }
+      val isRerun = config.optFailed
+      val rerunTests = if (isRerun) TestKinds.failedTests else Nil
+      def miscTests = partestTests ++ individualTests ++ greppedTests ++ rerunTests
+
+      val givenKinds = standardKinds filter config.parsed.isSet
+      val kinds = (
+        if (givenKinds.nonEmpty) givenKinds
+        else if (miscTests.isEmpty) standardKinds // If no kinds, --grep, or individual tests were given, assume --all
+        else Nil
+      )
+      val kindsTests = kinds flatMap testsFor
+
+      def testContributors = {
+        List(
+          if (partestTests.isEmpty) "" else "partest self-tests",
+          if (rerunTests.isEmpty) "" else "previously failed tests",
+          if (kindsTests.isEmpty) "" else s"${kinds.size} named test categories",
+          if (greppedTests.isEmpty) "" else s"${greppedTests.size} tests matching '$grepExpr'",
+          if (individualTests.isEmpty) "" else "specified tests"
+        ) filterNot (_ == "") mkString ", "
+      }
 
-    val allTests: Array[Path] = distinctBy(miscTests ++ kindsTests)(_.toCanonical) sortBy (_.toString) toArray
-    val grouped = (allTests groupBy kindOf).toArray sortBy (x => standardKinds indexOf x._1)
+      val allTests: Array[Path] = distinctBy(miscTests ++ kindsTests)(_.toCanonical) sortBy (_.toString) toArray
+      val grouped = (allTests groupBy kindOf).toArray sortBy (x => standardKinds indexOf x._1)
 
-    totalTests = allTests.size
-    expectedFailures = propOrNone("partest.errors") match {
-      case Some(num)  => num.toInt
-      case _          => 0
-    }
-    val expectedFailureMessage = if (expectedFailures == 0) "" else s" (expecting $expectedFailures to fail)"
-    echo(s"Selected $totalTests tests drawn from $testContributors$expectedFailureMessage\n")
-
-    val (_, millis) = timed {
-      for ((kind, paths) <- grouped) {
-        val num = paths.size
-        val ss = if (num == 1) "" else "s"
-        comment(s"starting $num test$ss in $kind")
-        val results = runTestsForFiles(paths map (_.jfile.getAbsoluteFile), kind)
-        val (passed, failed) = results partition (_.isOk)
-
-        passedTests ++= passed
-        failedTests ++= failed
-        if (failed.nonEmpty) {
-          comment(passFailString(passed.size, failed.size, 0) + " in " + kind)
+      totalTests = allTests.size
+      expectedFailures = propOrNone("partest.errors") match {
+        case Some(num)  => num.toInt
+        case _          => 0
+      }
+      val expectedFailureMessage = if (expectedFailures == 0) "" else s" (expecting $expectedFailures to fail)"
+      echo(s"Selected $totalTests tests drawn from $testContributors$expectedFailureMessage\n")
+
+      val (_, millis) = timed {
+        for ((kind, paths) <- grouped) {
+          val num = paths.size
+          val ss = if (num == 1) "" else "s"
+          comment(s"starting $num test$ss in $kind")
+          val results = suiteRunner.runTestsForFiles(paths map (_.jfile.getAbsoluteFile), kind)
+          val (passed, failed) = results partition (_.isOk)
+
+          passedTests ++= passed
+          failedTests ++= failed
+          if (failed.nonEmpty) {
+            comment(passFailString(passed.size, failed.size, 0) + " in " + kind)
+          }
+          echo("")
         }
-        echo("")
       }
+      this.elapsedMillis = millis
+      issueSummaryReport()
     }
-    this.elapsedMillis = millis
-    issueSummaryReport()
+    isSuccess
   }
 }
diff --git a/src/main/scala/scala/tools/partest/nest/AntRunner.scala b/src/main/scala/scala/tools/partest/nest/AntRunner.scala
index 786a7e9..12b4190 100644
--- a/src/main/scala/scala/tools/partest/nest/AntRunner.scala
+++ b/src/main/scala/scala/tools/partest/nest/AntRunner.scala
@@ -12,11 +12,12 @@ package nest
 import java.net.URLClassLoader
 
 // not using any Scala types to ease calling across different scala versions
-abstract class AntRunner(srcDir: String, testClassLoader: URLClassLoader, javaCmd: File, javacCmd: File, scalacArgs: Array[String], javaOpts: Option[Seq[String]]) extends SuiteRunner(
+abstract class AntRunner(srcDir: String, testClassLoader: URLClassLoader, javaCmd: File, javacCmd: File, scalacArgs: Array[String], javaOpts: Option[Seq[String]], nestUI: NestUI) extends SuiteRunner(
   testSourcePath = Option(srcDir) getOrElse PartestDefaults.sourcePath,
   new FileManager(testClassLoader = testClassLoader),
   updateCheck = false,
   failed  = false,
+  nestUI = nestUI,
   javaCmdPath = Option(javaCmd).map(_.getAbsolutePath) getOrElse PartestDefaults.javaCmd,
   javacCmdPath = Option(javacCmd).map(_.getAbsolutePath) getOrElse PartestDefaults.javacCmd,
   scalacExtraArgs = scalacArgs,
diff --git a/src/main/scala/scala/tools/partest/nest/ConsoleRunner.scala b/src/main/scala/scala/tools/partest/nest/ConsoleRunner.scala
index 462fc2f..5f515eb 100644
--- a/src/main/scala/scala/tools/partest/nest/ConsoleRunner.scala
+++ b/src/main/scala/scala/tools/partest/nest/ConsoleRunner.scala
@@ -3,33 +3,24 @@
  * @author Philipp Haller
  */
 
-package scala.tools
-package partest
+package scala.tools.partest
 package nest
 
-class ConsoleRunner(argstr: String) extends AbstractRunner(argstr) {
-
-  override val suiteRunner = new SuiteRunner (
-    testSourcePath = optSourcePath getOrElse PartestDefaults.sourcePath,
+class ConsoleRunner(val config: RunnerSpec.Config) extends AbstractRunner {
+  val suiteRunner = new SuiteRunner (
+    testSourcePath = config.optSourcePath getOrElse PartestDefaults.sourcePath,
     fileManager = new FileManager(ClassPath split PathResolver.Environment.javaUserClassPath map (Path(_))), // the script sets up our classpath for us via ant
-    updateCheck = optUpdateCheck,
-    failed = optFailed)
-
-  // So we can ctrl-C a test run and still hear all
-  // the buffered failure info.
-  scala.sys addShutdownHook issueSummaryReport()
-
-  override def run(): Unit = {
-    super.run()
-    System exit ( if (isSuccess) 0 else 1 )
-  }
-
-  run()
+    updateCheck = config.optUpdateCheck,
+    failed = config.optFailed,
+    nestUI = nestUI)
 }
 
 object ConsoleRunner {
   def main(args: Array[String]): Unit = {
-    new ConsoleRunner(args mkString " ")
+    val r = new ConsoleRunner(RunnerSpec.forArgs(args))
+    // So we can ctrl-C a test run and still hear all
+    // the buffered failure info.
+    scala.sys addShutdownHook r.issueSummaryReport()
+    System.exit( if (r.run) 0 else 1 )
   }
 }
-
diff --git a/src/main/scala/scala/tools/partest/nest/DirectCompiler.scala b/src/main/scala/scala/tools/partest/nest/DirectCompiler.scala
index 9c52624..2a5db56 100644
--- a/src/main/scala/scala/tools/partest/nest/DirectCompiler.scala
+++ b/src/main/scala/scala/tools/partest/nest/DirectCompiler.scala
@@ -107,7 +107,7 @@ class DirectCompiler(val runner: Runner) {
     }
 
     def ids = sources.map(_.testIdent) mkString space
-    vlog(s"% scalac $ids")
+    nestUI.vlog(s"% scalac $ids")
 
     def execCompile() =
       if (command.shouldStopWithInfo) {
diff --git a/src/main/scala/scala/tools/partest/nest/NestUI.scala b/src/main/scala/scala/tools/partest/nest/NestUI.scala
index e70f4e9..0913782 100644
--- a/src/main/scala/scala/tools/partest/nest/NestUI.scala
+++ b/src/main/scala/scala/tools/partest/nest/NestUI.scala
@@ -8,7 +8,7 @@ package nest
 
 import java.io.PrintWriter
 
-class Colors(enabled: => Boolean) {
+class Colors(enabled: Boolean) {
   import Console._
 
   val bold    = colored(BOLD)
@@ -16,8 +16,6 @@ class Colors(enabled: => Boolean) {
   val green   = colored(GREEN)
   val blue    = colored(BLUE)
   val red     = colored(RED)
-  val red_b   = colored(RED_B)
-  val green_b = colored(GREEN_B)
   val cyan    = colored(CYAN)
   val magenta = colored(MAGENTA)
 
@@ -25,33 +23,27 @@ class Colors(enabled: => Boolean) {
     s => if (enabled) code + s + RESET else s
 }
 
-object NestUI {
-  private val testNum = new java.util.concurrent.atomic.AtomicInteger(1)
-  @volatile private var testNumberFmt = "%3d"
-  // @volatile private var testNumber = 1
-  private def testNumber = testNumberFmt format testNum.getAndIncrement()
+class NestUI(val verbose: Boolean = false, val debug: Boolean = false, val terse: Boolean = false,
+             val diffOnFail: Boolean = false, val logOnFail: Boolean = false,
+             val colorEnabled: Boolean = sys.props contains "partest.colors") {
+  private[this] val testNum = new java.util.concurrent.atomic.AtomicInteger(1)
+  @volatile private[this] var testNumberFmt = "%3d"
+  private[this] def testNumber = testNumberFmt format testNum.getAndIncrement()
   def resetTestNumber(max: Int = -1) {
     testNum set 1
     val width = if (max > 0) max.toString.length else 3
     testNumberFmt = s"%${width}d"
   }
 
-  var colorEnabled = sys.props contains "partest.colors"
   val color = new Colors(colorEnabled)
   import color._
 
-  val NONE = 0
-  val SOME = 1
-  val MANY = 2
+  private[this] val (_outline, _success, _failure, _warning, _default) =
+    if (colorEnabled) (Console.BOLD, Console.BOLD + Console.GREEN, Console.BOLD + Console.RED, Console.BOLD + Console.YELLOW, Console.RESET)
+    else ("", "", "", "", "")
 
-  private var _outline = ""
-  private var _success = ""
-  private var _failure = ""
-  private var _warning = ""
-  private var _default = ""
-
-  private var dotCount = 0
-  private val DotWidth = 72
+  private[this] var dotCount = 0
+  private[this] val DotWidth = 72
 
   def leftFlush() {
     if (dotCount != 0) {
@@ -73,8 +65,8 @@ object NestUI {
     f"$word $testNumber - $testIdent%-40s$reasonString"
   }
 
-  def reportTest(state: TestState, info: TestInfo) =
-    if (isTerse && state.isOk) {
+  def reportTest(state: TestState, info: TestInfo): Unit = {
+    if (terse && state.isOk) {
       if (dotCount >= DotWidth) {
         outline("\n.")
         dotCount = 1
@@ -89,24 +81,25 @@ object NestUI {
           echo(bold(cyan(s"##### Log file '${info.logFile}' from failed test #####\n")))
           echo(info.logFile.fileContents)
         }
-        if (isDiffy) {
+        if (diffOnFail) {
           val differ = bold(red("% ")) + "diff "
           val diffed = state.transcript find (_ startsWith differ)
           diffed match {
             case Some(diff) => echo(diff)
-            case None if !isLogging && !isPartestVerbose => showLog()
+            case None if !logOnFail && !verbose => showLog()
             case _ => ()
           }
         }
-        if (isLogging) showLog()
+        if (logOnFail) showLog()
       }
     }
+  }
 
   def echo(message: String): Unit = synchronized {
     leftFlush()
     print(message + "\n")
   }
-  def chatty(msg: String) = if (isVerbose) echo(msg)
+  def chatty(msg: String): Unit = if (verbose) echo(msg)
 
   def echoSkipped(msg: String) = echo(yellow(msg))
   def echoPassed(msg: String)  = echo(bold(green(msg)))
@@ -114,22 +107,6 @@ object NestUI {
   def echoMixed(msg: String)   = echo(bold(yellow(msg)))
   def echoWarning(msg: String) = echo(bold(red(msg)))
 
-  def initialize(number: Int) = number match {
-    case MANY =>
-      _outline = Console.BOLD + Console.BLACK
-      _success = Console.BOLD + Console.GREEN
-      _failure = Console.BOLD +  Console.RED
-      _warning = Console.BOLD + Console.YELLOW
-      _default = Console.RESET
-    case SOME =>
-      _outline = Console.BOLD + Console.BLACK
-      _success = Console.RESET
-      _failure = Console.BOLD + Console.BLACK
-      _warning = Console.BOLD + Console.BLACK
-      _default = Console.RESET
-    case _ =>
-  }
-
   def outline(msg: String) = print(_outline + msg + _default)
   def outline(msg: String, wr: PrintWriter) = synchronized {
     wr.print(_outline + msg + _default)
@@ -158,39 +135,16 @@ object NestUI {
     sys.exit(1)
   }
 
-  var _verbose = false
-  var _debug = false
-  var _terse = false
-  var _diff  = false
-  var _logging = false
+  def verbose(msg: String): Unit =
+    if (verbose) System.err.println(msg)
 
-  def isVerbose = _verbose
-  def isDebug = _debug
-  def isTerse = _terse
-  def isDiffy = _diff
-  def isLogging = _logging
+  def debug(msg: String): Unit =
+    if (debug) System.err.println(msg)
 
-  def setVerbose() {
-    _verbose = true
-  }
-  def setDebug() {
-    _debug = true
-  }
-  def setTerse() {
-    _terse = true
-  }
-  def setDiffOnFail() {
-    _diff = true
-  }
-  def setLogOnFail() {
-    _logging = true
-  }
-  def verbose(msg: String) {
-    if (isVerbose)
-      System.err.println(msg)
-  }
-  def debug(msg: String) {
-    if (isDebug)
-      System.err.println(msg)
+  def showAllJVMInfo(): Unit = {
+    vlog(vmArgString)
+    vlog(allPropertiesString)
   }
+
+  def vlog(msg: => String) = if (verbose) System.err.println(msg)
 }
diff --git a/src/main/scala/scala/tools/partest/nest/Runner.scala b/src/main/scala/scala/tools/partest/nest/Runner.scala
index 0b9106c..0478a7d 100644
--- a/src/main/scala/scala/tools/partest/nest/Runner.scala
+++ b/src/main/scala/scala/tools/partest/nest/Runner.scala
@@ -26,22 +26,6 @@ import TestState.{ Pass, Fail, Crash, Uninitialized, Updated }
 
 import FileManager.{ compareFiles, compareContents, joinPaths, withTempFile }
 
-class TestTranscript {
-  import NestUI.color._
-  private val buf = ListBuffer[String]()
-  private def pass(s: String) = bold(green("% ")) + s
-  private def fail(s: String) = bold(red("% ")) + s
-
-  def add(action: String): this.type = { buf += action ; this }
-  def append(text: String) { val s = buf.last ; buf.trimEnd(1) ; buf += (s + text) }
-
-  // Colorize prompts according to pass/fail
-  def fail: List[String] = buf.toList match {
-    case Nil  => Nil
-    case xs   => (xs.init map pass) :+ fail(xs.last)
-  }
-}
-
 trait TestInfo {
   /** pos/t1234 */
   def testIdent: String
@@ -70,7 +54,7 @@ trait TestInfo {
 }
 
 /** Run a single test. Rubber meets road. */
-class Runner(val testFile: File, val suiteRunner: SuiteRunner) extends TestInfo {
+class Runner(val testFile: File, val suiteRunner: SuiteRunner, val nestUI: NestUI) extends TestInfo {
 
   import suiteRunner.{fileManager => fm, _}
   val fileManager = fm
@@ -108,7 +92,7 @@ class Runner(val testFile: File, val suiteRunner: SuiteRunner) extends TestInfo
 
   def showCrashInfo(t: Throwable) {
     System.err.println(s"Crashed running test $testIdent: " + t)
-    if (!isPartestTerse)
+    if (!nestUI.terse)
       System.err.println(stackTraceString(t))
   }
   protected def crashHandler: PartialFunction[Throwable, TestState] = {
@@ -173,7 +157,7 @@ class Runner(val testFile: File, val suiteRunner: SuiteRunner) extends TestInfo
     val argsFile  = testFile changeExtension "javaopts"
     val argString = file2String(argsFile)
     if (argString != "")
-      NestUI.verbose("Found javaopts file '%s', using options: '%s'".format(argsFile, argString))
+      nestUI.verbose("Found javaopts file '%s', using options: '%s'".format(argsFile, argString))
 
     val testFullPath = testFile.getAbsolutePath
 
@@ -185,7 +169,7 @@ class Runner(val testFile: File, val suiteRunner: SuiteRunner) extends TestInfo
     //
     // debug: Found javaopts file 'files/shootout/message.scala-2.javaopts', using options: '-Xss32k'
     // debug: java -Xss32k -Xss2m -Xms256M -Xmx1024M -classpath [...]
-    val extras = if (isPartestDebug) List("-Dpartest.debug=true") else Nil
+    val extras = if (nestUI.debug) List("-Dpartest.debug=true") else Nil
     val propertyOptions = List(
       "-Dfile.encoding=UTF-8",
       "-Djava.library.path="+logFile.getParentFile.getAbsolutePath,
@@ -229,11 +213,11 @@ class Runner(val testFile: File, val suiteRunner: SuiteRunner) extends TestInfo
       try p.exitValue
       catch {
         case e: InterruptedException =>
-          NestUI verbose s"Interrupted waiting for command to finish (${args mkString " "})"
+          nestUI.verbose(s"Interrupted waiting for command to finish (${args mkString " "})")
           p.destroy
           nonzero
         case t: Throwable =>
-          NestUI verbose s"Exception waiting for command to finish: $t (${args mkString " "})"
+          nestUI.verbose(s"Exception waiting for command to finish: $t (${args mkString " "})")
           p.destroy
           throw t
       }
@@ -265,7 +249,7 @@ class Runner(val testFile: File, val suiteRunner: SuiteRunner) extends TestInfo
   }
 
   def fail(what: Any) = {
-    NestUI.verbose("scalac: compilation of "+what+" failed\n")
+    nestUI.verbose("scalac: compilation of "+what+" failed\n")
     false
   }
 
@@ -381,8 +365,8 @@ class Runner(val testFile: File, val suiteRunner: SuiteRunner) extends TestInfo
     )
 
     logFile.mapInPlace(canonicalize)(lineFilter)
-    if (isPartestVerbose && elisions.nonEmpty) {
-      import NestUI.color._
+    if (nestUI.verbose && elisions.nonEmpty) {
+      import nestUI.color._
       val emdash = bold(yellow("--"))
       pushTranscript(s"filtering ${logFile.getName}$EOL${elisions mkString (emdash, EOL + emdash, EOL)}")
     }
@@ -400,7 +384,7 @@ class Runner(val testFile: File, val suiteRunner: SuiteRunner) extends TestInfo
     pushTranscript(s"diff $logFile $checkFile")
     nextTestAction(updating) {
       case Some(true)  =>
-        NestUI.verbose("Updating checkfile " + checkFile)
+        nestUI.verbose("Updating checkfile " + checkFile)
         checkFile writeAll file2String(logFile)
         genUpdated()
       case Some(false) =>
@@ -549,7 +533,7 @@ class Runner(val testFile: File, val suiteRunner: SuiteRunner) extends TestInfo
   // Apache Ant 1.6 or newer
   def ant(args: Seq[String], output: File): Boolean = {
     val antOptions =
-      if (NestUI._verbose) List("-verbose", "-noinput")
+      if (nestUI.verbose) List("-verbose", "-noinput")
       else List("-noinput")
     val cmd = javaCmdPath +: (
       suiteRunner.javaOpts.split(' ').map(_.trim).filter(_ != "") ++ Seq(
@@ -568,14 +552,14 @@ class Runner(val testFile: File, val suiteRunner: SuiteRunner) extends TestInfo
     val succeeded = try {
       val binary = "-Dbinary="+ fileManager.distKind
       val args = Array(binary, "-logfile", logFile.getPath, "-file", testFile.getPath)
-      NestUI.verbose("ant "+args.mkString(" "))
+      nestUI.verbose("ant "+args.mkString(" "))
 
       pushTranscript(s"ant ${args.mkString(" ")}")
       nextTestActionExpectTrue("ant failed", ant(args, logFile)) && diffIsOk
     }
     catch { // *catch-all*
       case e: Exception =>
-        NestUI.warning("caught "+e)
+        nestUI.warning("caught "+e)
         false
     }
 
@@ -592,7 +576,7 @@ class Runner(val testFile: File, val suiteRunner: SuiteRunner) extends TestInfo
   }
 
   def runScalacheckTest() = runTestCommon {
-    NestUI verbose f"compilation of $testFile succeeded%n"
+    nestUI.verbose(f"compilation of $testFile succeeded%n")
 
     val logWriter = new PrintStream(new FileOutputStream(logFile), true)
 
@@ -624,7 +608,7 @@ class Runner(val testFile: File, val suiteRunner: SuiteRunner) extends TestInfo
       val claas       = "Test"
       val fingerprint = f.tests collectFirst { case x: SubclassFingerprint if x.isModule => x }
       val args        = toolArgs("scalacheck")
-      vlog(s"Run $testFile with args $args")
+      nestUI.vlog(s"Run $testFile with args $args")
       // set the context class loader for scaladoc/scalacheck tests (FIX ME)
       ScalaClassLoader(fileManager.testClassLoader).asContext {
         r.run(claas, fingerprint.get, handler, args.toArray)    // synchronous?
@@ -641,7 +625,7 @@ class Runner(val testFile: File, val suiteRunner: SuiteRunner) extends TestInfo
     val prompt = "\nnsc> "
     val (swr, wr) = newTestWriters()
 
-    NestUI.verbose(s"$this running test $fileBase")
+    nestUI.verbose(s"$this running test $fileBase")
     val dir = parentFile
     val resFile = new File(dir, fileBase + ".res")
 
@@ -649,7 +633,7 @@ class Runner(val testFile: File, val suiteRunner: SuiteRunner) extends TestInfo
     // $SCALAC -d "$os_dstbase".obj -Xresident -sourcepath . "$@"
     val sourcedir  = logFile.getParentFile.getAbsoluteFile
     val sourcepath = sourcedir.getAbsolutePath+File.separator
-    NestUI.verbose("sourcepath: "+sourcepath)
+    nestUI.verbose("sourcepath: "+sourcepath)
 
     val argList = List(
       "-d", outDir.getAbsoluteFile.getPath,
@@ -769,7 +753,7 @@ class Runner(val testFile: File, val suiteRunner: SuiteRunner) extends TestInfo
   def cleanup() {
     if (lastState.isOk)
       logFile.delete()
-    if (!isPartestDebug)
+    if (!nestUI.debug)
       Directory(outDir).deleteRecursively()
   }
 
@@ -787,6 +771,7 @@ class SuiteRunner(
   val fileManager: FileManager,
   val updateCheck: Boolean,
   val failed: Boolean,
+  val nestUI: NestUI,
   val javaCmdPath: String = PartestDefaults.javaCmd,
   val javacCmdPath: String = PartestDefaults.javacCmd,
   val scalacExtraArgs: Seq[String] = Seq.empty,
@@ -824,7 +809,7 @@ class SuiteRunner(
   def onFinishTest(testFile: File, result: TestState): TestState = result
 
   def runTest(testFile: File): TestState = {
-    val runner = new Runner(testFile, this)
+    val runner = new Runner(testFile, this, nestUI)
 
     // when option "--failed" is provided execute test only if log
     // is present (which means it failed before)
@@ -837,7 +822,7 @@ class SuiteRunner(
           catch {
             case t: Throwable => throw new RuntimeException(s"Error running $testFile", t)
           }
-        NestUI.reportTest(state, runner)
+        nestUI.reportTest(state, runner)
         runner.cleanup()
         state
       }
@@ -845,7 +830,7 @@ class SuiteRunner(
   }
 
   def runTestsForFiles(kindFiles: Array[File], kind: String): Array[TestState] = {
-    NestUI.resetTestNumber(kindFiles.size)
+    nestUI.resetTestNumber(kindFiles.size)
 
     val pool              = Executors newFixedThreadPool numThreads
     val futures           = kindFiles map (f => pool submit callable(runTest(f.getAbsoluteFile)))
@@ -858,9 +843,9 @@ class SuiteRunner(
       case Failure(e) =>
         e match {
           case TimeoutException(d)      =>
-            NestUI warning "Thread pool timeout elapsed before all tests were complete!"
+            nestUI.warning("Thread pool timeout elapsed before all tests were complete!")
           case ie: InterruptedException =>
-            NestUI warning "Thread pool was interrupted"
+            nestUI.warning("Thread pool was interrupted")
             ie.printStackTrace()
         }
         pool.shutdownNow()     // little point in continuing
@@ -875,6 +860,24 @@ class SuiteRunner(
         results.flatten
     }
   }
+
+  class TestTranscript {
+    private val buf = ListBuffer[String]()
+
+    def add(action: String): this.type = { buf += action ; this }
+    def append(text: String) { val s = buf.last ; buf.trimEnd(1) ; buf += (s + text) }
+
+    // Colorize prompts according to pass/fail
+    def fail: List[String] = {
+      import nestUI.color._
+      def pass(s: String) = bold(green("% ")) + s
+      def fail(s: String) = bold(red("% ")) + s
+      buf.toList match {
+        case Nil  => Nil
+        case xs   => (xs.init map pass) :+ fail(xs.last)
+      }
+    }
+  }
 }
 
 case class TimeoutException(duration: Duration) extends RuntimeException
diff --git a/src/main/scala/scala/tools/partest/nest/RunnerSpec.scala b/src/main/scala/scala/tools/partest/nest/RunnerSpec.scala
index 974a5e9..229ac59 100644
--- a/src/main/scala/scala/tools/partest/nest/RunnerSpec.scala
+++ b/src/main/scala/scala/tools/partest/nest/RunnerSpec.scala
@@ -2,7 +2,7 @@ package scala.tools.partest.nest
 
 import language.postfixOps
 
-import scala.tools.cmd.{ CommandLine, Interpolation, Meta, Reference, Spec }
+import scala.tools.cmd.{ CommandLine, Interpolation, Meta, Reference, Spec, Instance }
 
 trait RunnerSpec extends Spec with Meta.StdOpts with Interpolation {
   def referenceSpec       = RunnerSpec
@@ -49,6 +49,10 @@ trait RunnerSpec extends Spec with Meta.StdOpts with Interpolation {
 }
 
 object RunnerSpec extends RunnerSpec with Reference {
+  trait Config extends RunnerSpec with Instance
+
   type ThisCommandLine = CommandLine
   def creator(args: List[String]): ThisCommandLine = new CommandLine(RunnerSpec, args)
+
+  def forArgs(args: Array[String]): Config = new { val parsed = creator(args.toList) } with Config
 }
diff --git a/src/main/scala/scala/tools/partest/package.scala b/src/main/scala/scala/tools/partest/package.scala
index 43fb611..0d56ac3 100644
--- a/src/main/scala/scala/tools/partest/package.scala
+++ b/src/main/scala/scala/tools/partest/package.scala
@@ -7,7 +7,6 @@ package scala.tools
 import java.util.concurrent.{ Callable, ExecutorService }
 import scala.concurrent.duration.Duration
 import scala.sys.process.javaVmArguments
-import scala.tools.partest.nest.NestUI
 import scala.tools.nsc.util.{ ScalaClassLoader, Exceptional }
 
 package object partest {
@@ -181,15 +180,4 @@ package object partest {
     import scala.collection.JavaConversions._
     System.getProperties.toList.sorted map { case (k, v) => "%s -> %s\n".format(k, v) } mkString ""
   }
-
-  def showAllJVMInfo() {
-    vlog(vmArgString)
-    vlog(allPropertiesString)
-  }
-
-  def isPartestTerse   = NestUI.isTerse
-  def isPartestDebug   = NestUI.isDebug
-  def isPartestVerbose = NestUI.isVerbose
-
-  def vlog(msg: => String) = if (isPartestVerbose) System.err.println(msg)
 }
diff --git a/src/main/scala/scala/tools/partest/sbt/Framework.scala b/src/main/scala/scala/tools/partest/sbt/Framework.scala
index 489dae6..068910a 100644
--- a/src/main/scala/scala/tools/partest/sbt/Framework.scala
+++ b/src/main/scala/scala/tools/partest/sbt/Framework.scala
@@ -1,6 +1,6 @@
 package scala.tools.partest.sbt
 
-import scala.tools.partest.nest.SBTRunner
+import scala.tools.partest.nest.RunnerSpec
 import _root_.sbt.testing._
 import java.net.URLClassLoader
 import java.io.File
@@ -34,7 +34,8 @@ case class PartestTask(taskDef: TaskDef, args: Array[String]) extends Task {
   def execute(eventHandler: EventHandler, loggers: Array[Logger]): Array[Task] = {
     val forkedCp    = scala.util.Properties.javaClassPath
     val classLoader = new URLClassLoader(forkedCp.split(java.io.File.pathSeparator).map(new File(_).toURI.toURL))
-    val runner      = new SBTRunner(taskDef.fingerprint(), eventHandler, loggers, "files", classLoader, null, null, Array.empty[String], args)
+    val config      = RunnerSpec.forArgs(args.filter(a => !a.startsWith("-D")))
+    val runner      = new SBTRunner(config, taskDef.fingerprint(), eventHandler, loggers, "files", classLoader, null, null, Array.empty[String], args)
 
     if (Runtime.getRuntime().maxMemory() / (1024*1024) < 800)
       loggers foreach (_.warn(s"""Low heap size detected (~ ${Runtime.getRuntime().maxMemory() / (1024*1024)}M). Please add the following to your build.sbt: javaOptions in Test += "-Xmx1G""""))
diff --git a/src/main/scala/scala/tools/partest/nest/SBTRunner.scala b/src/main/scala/scala/tools/partest/sbt/SBTRunner.scala
similarity index 63%
rename from src/main/scala/scala/tools/partest/nest/SBTRunner.scala
rename to src/main/scala/scala/tools/partest/sbt/SBTRunner.scala
index a79dfcc..d42d082 100644
--- a/src/main/scala/scala/tools/partest/nest/SBTRunner.scala
+++ b/src/main/scala/scala/tools/partest/sbt/SBTRunner.scala
@@ -6,26 +6,42 @@
 **                          |/                                          **
 \*                                                                      */
 
-package scala.tools.partest
-package nest
+package scala.tools.partest.sbt
 
-import _root_.sbt.testing._
 import java.net.URLClassLoader
-import TestState._
 
-class SBTRunner(partestFingerprint: Fingerprint, eventHandler: EventHandler, loggers: Array[Logger],
-    srcDir: String, testClassLoader: URLClassLoader, javaCmd: File, javacCmd: File, scalacArgs: Array[String], args: Array[String])
-    extends AbstractRunner(args.filter(a => !a.startsWith("-D")).mkString(" ")) {
+import _root_.sbt.testing._
+
+import scala.tools.partest.TestState._
+import scala.tools.partest._
+import scala.tools.partest.nest.{AbstractRunner, FileManager, RunnerSpec, SuiteRunner}
+
+class SBTRunner(val config: RunnerSpec.Config,
+                partestFingerprint: Fingerprint, eventHandler: EventHandler, loggers: Array[Logger],
+                srcDir: String, testClassLoader: URLClassLoader, javaCmd: File, javacCmd: File,
+                scalacArgs: Array[String], args: Array[String]) extends AbstractRunner {
 
   // no summary, SBT will do that for us
-  printSummary = false
-  partestCmd   = "partest"
+  override protected val printSummary = false
+  override protected val partestCmd   = "partest"
 
   val defs = {
     val Def = "-D([^=]*)=(.*)".r
     args.collect { case Def(k, v) => (k, v) }
   }
 
+  // Enable colors if there's an explicit override or all loggers support them
+  override protected val colorEnabled = {
+    val ptOverride = defs.collect { case ("partest.colors", v) => v.toBoolean }.lastOption
+    ptOverride.getOrElse {
+      val sbtOverride1 = sys.props.get("sbt.log.format").map(_.toBoolean)
+      val sbtOverride2 = sys.props.get("sbt.log.noformat").map(s => !s.toBoolean)
+      sbtOverride1.orElse(sbtOverride2).getOrElse {
+        loggers.forall(_.ansiCodesSupported())
+      }
+    }
+  }
+
   val javaOpts = {
     val l = defs.collect { case ("partest.java_opts", v) => v }
     if(l.isEmpty) PartestDefaults.javaOpts
@@ -38,11 +54,12 @@ class SBTRunner(partestFingerprint: Fingerprint, eventHandler: EventHandler, log
     else l.mkString(" ")
   }
 
-  override val suiteRunner = new SuiteRunner(
-    testSourcePath = optSourcePath orElse Option(srcDir) getOrElse PartestDefaults.sourcePath,
+  val suiteRunner = new SuiteRunner(
+    testSourcePath = config.optSourcePath orElse Option(srcDir) getOrElse PartestDefaults.sourcePath,
     new FileManager(testClassLoader = testClassLoader),
-    updateCheck = optUpdateCheck,
-    failed  = optFailed,
+    updateCheck = config.optUpdateCheck,
+    failed  = config.optFailed,
+    nestUI = nestUI,
     javaCmdPath = Option(javaCmd).map(_.getAbsolutePath) getOrElse PartestDefaults.javaCmd,
     javacCmdPath = Option(javacCmd).map(_.getAbsolutePath) getOrElse PartestDefaults.javacCmd,
     scalacExtraArgs = scalacArgs,