diff --git a/.travis.yml b/.travis.yml
index 8ecb9677a..c7d814a1c 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,11 +1,15 @@
-language: scala
-scala: 2.12.7
+language: java
 os: linux
-jdk: oraclejdk8
+jdk: openjdk8
+git:
+  depth: false # https://stackoverflow.com/a/51727114/3714539
 before_install:
-  - git fetch --tags
-script:
-  - scripts/travis.sh
+  - mkdir .bin
+  - curl -Lo .bin/sbt https://raw.githubusercontent.com/coursier/sbt-extras/77c93346a2b52cf35cc72382125cfdbb25a00197/sbt
+  - chmod +x .bin/sbt
+  - export PATH="$(pwd)/.bin:$PATH"
+  - export TRAVIS_SCALA_VERSION=2.12.8
+script: scripts/travis.sh
 stages:
   - name: test
   - name: release
diff --git a/appveyor.yml b/appveyor.yml
index 1aed4d288..5c52755c0 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -2,18 +2,12 @@
 version: '{build}'
 os: Windows Server 2012
 install:
-  - ps: |
-      Add-Type -AssemblyName System.IO.Compression.FileSystem
-      if (!(Test-Path -Path "C:\sbt" )) {
-        (new-object System.Net.WebClient).DownloadFile(
-          'https://dl.bintray.com/sbt/native-packages/sbt/0.13.8/sbt-0.13.8.zip',
-          'C:\sbt-bin.zip'
-        )
-        [System.IO.Compression.ZipFile]::ExtractToDirectory("C:\sbt-bin.zip", "C:\sbt")
-      }
+  - cmd: mkdir C:\sbt
+  - cmd: curl -Lo C:\sbt\sbt https://github.com/coursier/sbt-launcher/releases/download/v1.2.5/csbt
+  - cmd: curl -Lo C:\sbt\sbt.bat https://github.com/coursier/sbt-launcher/releases/download/v1.2.5/csbt.bat
   - cmd: SET JAVA_HOME=C:\Program Files\Java\jdk1.8.0
-  - cmd: SET PATH=C:\sbt\sbt\bin;%JAVA_HOME%\bin;%PATH%
-  - cmd: SET SBT_OPTS=-Xmx4g -Xss2m
+  - cmd: SET PATH=C:\sbt;%JAVA_HOME%\bin;%PATH%
+  - cmd: SET JAVA_OPTS=-Xmx4g -Xss2m
   - git submodule update --init --recursive
 environment:
   TEST_REPOSITORY_HOST: localhost
@@ -22,6 +16,7 @@ environment:
   TEST_REPOSITORY_PASSWORD: pass
   TEST_REPOSITORY: http://localhost:8080
 build_script:
+  - cmd: .\metadata\coursier fetch io.get-coursier:http-server_2.12:1.0.0
   - ps: Start-Job -filepath .\metadata\scripts\start-it-auth-server.ps1 -ArgumentList $pwd\metadata, $env:TEST_REPOSITORY_HOST, $env:TEST_REPOSITORY_PORT, $env:TEST_REPOSITORY_USER, $env:TEST_REPOSITORY_PASSWORD
 test_script:
   - sbt ++2.12.7 "sbt-lm-coursier/scripted shared-2/simple" sbt-coursier/scripted sbt-shading/scripted
diff --git a/build.sbt b/build.sbt
index bf6e64fbd..70b49c7a2 100644
--- a/build.sbt
+++ b/build.sbt
@@ -15,16 +15,13 @@ inThisBuild(List(
   )
 ))
 
-val coursierVersion = "1.1.0-M12"
-
 lazy val `lm-coursier` = project
   .in(file("modules/lm-coursier"))
   .enablePlugins(ContrabandPlugin)
   .settings(
     shared,
     libraryDependencies ++= Seq(
-      "io.get-coursier" %% "coursier" % coursierVersion,
-      "io.get-coursier" %% "coursier-extra" % coursierVersion,
+      "io.get-coursier" %% "coursier" % "1.1.0-M13",
       // We depend on librarymanagement-ivy rather than just
       // librarymanagement-core to handle the ModuleDescriptor passed
       // to DependencyResolutionInterface.update, which is an
diff --git a/metadata b/metadata
index a0752761c..eb8d9e382 160000
--- a/metadata
+++ b/metadata
@@ -1 +1 @@
-Subproject commit a0752761c58fddd917f8b0c4bc8e69c8111ea606
+Subproject commit eb8d9e382fe9640dd4bea86ecf5d4ba99c8995a0
diff --git a/modules/lm-coursier/src/main/scala/coursier/lmcoursier/ArtifactsRun.scala b/modules/lm-coursier/src/main/scala/coursier/lmcoursier/ArtifactsRun.scala
index 7d995391c..41737d70e 100644
--- a/modules/lm-coursier/src/main/scala/coursier/lmcoursier/ArtifactsRun.scala
+++ b/modules/lm-coursier/src/main/scala/coursier/lmcoursier/ArtifactsRun.scala
@@ -6,7 +6,7 @@ import coursier.cache.FileCache
 import coursier.Artifact
 import coursier.cache.loggers.{ProgressBarRefreshDisplay, RefreshLogger}
 import coursier.core.Type
-import coursier.util.Schedulable
+import coursier.util.Sync
 import sbt.util.Logger
 
 object ArtifactsRun {
@@ -29,7 +29,7 @@ object ArtifactsRun {
         else
           ""
 
-      Schedulable.withFixedThreadPool(params.cacheParams.parallel) { pool =>
+      Sync.withFixedThreadPool(params.cacheParams.parallel) { pool =>
 
         coursier.Artifacts()
           .withResolutions(params.resolutions)
diff --git a/modules/lm-coursier/src/main/scala/coursier/lmcoursier/CoursierDependencyResolution.scala b/modules/lm-coursier/src/main/scala/coursier/lmcoursier/CoursierDependencyResolution.scala
index b106635c4..0f771d70b 100644
--- a/modules/lm-coursier/src/main/scala/coursier/lmcoursier/CoursierDependencyResolution.scala
+++ b/modules/lm-coursier/src/main/scala/coursier/lmcoursier/CoursierDependencyResolution.scala
@@ -4,9 +4,9 @@ import java.io.File
 
 import _root_.coursier.{Artifact, Organization, Resolution, organizationString}
 import _root_.coursier.core.{Classifier, Configuration, ModuleName}
-import _root_.coursier.extra.Typelevel
 import _root_.coursier.lmcoursier.Inputs.withAuthenticationByHost
 import coursier.cache.{CacheDefaults, CachePolicy}
+import coursier.internal.Typelevel
 import coursier.params.CacheParams
 import sbt.internal.librarymanagement.IvySbt
 import sbt.librarymanagement._
@@ -108,9 +108,9 @@ class CoursierDependencyResolution(conf: CoursierConfiguration) extends Dependen
     val dependencies = module0
       .dependencies
       .flatMap { d =>
-        // crossVersion already taken into account, wiping it here
-        val d0 = d.withCrossVersion(CrossVersion.Disabled())
-        FromSbt.dependencies(d0, sv, sbv)
+        // crossVersion sometimes already taken into account (when called via the update task), sometimes not
+        // (e.g. sbt-dotty 0.13.0-RC1)
+        FromSbt.dependencies(d, sv, sbv, optionalCrossVer = true)
       }
       .map {
         case (config, dep) =>
diff --git a/modules/lm-coursier/src/main/scala/coursier/lmcoursier/FromSbt.scala b/modules/lm-coursier/src/main/scala/coursier/lmcoursier/FromSbt.scala
index d9ea873cb..25b15b3e7 100644
--- a/modules/lm-coursier/src/main/scala/coursier/lmcoursier/FromSbt.scala
+++ b/modules/lm-coursier/src/main/scala/coursier/lmcoursier/FromSbt.scala
@@ -2,7 +2,7 @@ package coursier.lmcoursier
 
 import coursier.ivy.IvyRepository
 import coursier.ivy.IvyXml.{mappings => ivyXmlMappings}
-import java.net.{MalformedURLException, URL}
+import java.net.MalformedURLException
 
 import coursier.cache.CacheUrl
 import coursier.{Attributes, Dependency, Module}
@@ -17,9 +17,21 @@ object FromSbt {
   def sbtModuleIdName(
     moduleId: ModuleID,
     scalaVersion: => String,
-    scalaBinaryVersion: => String
-  ): String =
-    sbtCrossVersionName(moduleId.name, moduleId.crossVersion, scalaVersion, scalaBinaryVersion)
+    scalaBinaryVersion: => String,
+    optionalCrossVer: Boolean = false
+  ): String = {
+    val name0 = moduleId.name
+    val updatedName = sbtCrossVersionName(name0, moduleId.crossVersion, scalaVersion, scalaBinaryVersion)
+    if (!optionalCrossVer || updatedName.length <= name0.length)
+      updatedName
+    else {
+      val suffix = updatedName.substring(name0.length)
+      if (name0.endsWith(suffix))
+        name0
+      else
+        updatedName
+    }
+  }
 
   def sbtCrossVersionName(
     name: String,
@@ -40,10 +52,11 @@ object FromSbt {
   def moduleVersion(
     module: ModuleID,
     scalaVersion: String,
-    scalaBinaryVersion: String
+    scalaBinaryVersion: String,
+    optionalCrossVer: Boolean = false
   ): (Module, String) = {
 
-    val fullName = sbtModuleIdName(module, scalaVersion, scalaBinaryVersion)
+    val fullName = sbtModuleIdName(module, scalaVersion, scalaBinaryVersion, optionalCrossVer)
 
     val module0 = Module(Organization(module.organization), ModuleName(fullName), FromSbt.attributes(module.extraDependencyAttributes))
     val version = module.revision
@@ -54,12 +67,13 @@ object FromSbt {
   def dependencies(
     module: ModuleID,
     scalaVersion: String,
-    scalaBinaryVersion: String
+    scalaBinaryVersion: String,
+    optionalCrossVer: Boolean = false
   ): Seq[(Configuration, Dependency)] = {
 
     // TODO Warn about unsupported properties in `module`
 
-    val (module0, version) = moduleVersion(module, scalaVersion, scalaBinaryVersion)
+    val (module0, version) = moduleVersion(module, scalaVersion, scalaBinaryVersion, optionalCrossVer)
 
     val dep = Dependency(
       module0,
diff --git a/modules/lm-coursier/src/main/scala/coursier/lmcoursier/ResolutionParams.scala b/modules/lm-coursier/src/main/scala/coursier/lmcoursier/ResolutionParams.scala
index f980bcf6f..9c8f8e576 100644
--- a/modules/lm-coursier/src/main/scala/coursier/lmcoursier/ResolutionParams.scala
+++ b/modules/lm-coursier/src/main/scala/coursier/lmcoursier/ResolutionParams.scala
@@ -3,8 +3,9 @@ package coursier.lmcoursier
 import java.io.File
 
 import coursier.cache.CacheLogger
-import coursier.{FallbackDependenciesRepository, ProjectCache}
+import coursier.ProjectCache
 import coursier.core._
+import coursier.util.InMemoryRepository
 import sbt.librarymanagement.{Resolver, URLRepository}
 
 final case class ResolutionParams(
@@ -33,7 +34,7 @@ final case class ResolutionParams(
       }.toMap
 
       Seq(
-        FallbackDependenciesRepository(map)
+        InMemoryRepository(map)
       )
     }
 
diff --git a/modules/lm-coursier/src/main/scala/coursier/lmcoursier/ResolutionRun.scala b/modules/lm-coursier/src/main/scala/coursier/lmcoursier/ResolutionRun.scala
index 7ad211c02..8a07af83d 100644
--- a/modules/lm-coursier/src/main/scala/coursier/lmcoursier/ResolutionRun.scala
+++ b/modules/lm-coursier/src/main/scala/coursier/lmcoursier/ResolutionRun.scala
@@ -6,7 +6,7 @@ import coursier.cache.loggers.{ProgressBarRefreshDisplay, RefreshLogger}
 import coursier.core._
 import coursier.ivy.IvyRepository
 import coursier.maven.MavenRepository
-import coursier.util.Schedulable
+import coursier.util.Sync
 import sbt.util.Logger
 
 object ResolutionRun {
@@ -64,7 +64,7 @@ object ResolutionRun {
     if (verbosityLevel >= 2)
       log.info(initialMessage)
 
-    Schedulable.withFixedThreadPool(params.cacheParams.parallel) { pool =>
+    Sync.withFixedThreadPool(params.cacheParams.parallel) { pool =>
 
       Resolve()
         .withDependencies(
diff --git a/modules/lm-coursier/src/main/scala/coursier/lmcoursier/ToSbt.scala b/modules/lm-coursier/src/main/scala/coursier/lmcoursier/ToSbt.scala
index 258dd163b..53143405e 100644
--- a/modules/lm-coursier/src/main/scala/coursier/lmcoursier/ToSbt.scala
+++ b/modules/lm-coursier/src/main/scala/coursier/lmcoursier/ToSbt.scala
@@ -218,7 +218,11 @@ object ToSbt {
 
     val configReports = configs.map {
       case (config, extends0) =>
-        val configDeps = extends0.toSeq.sortBy(_.value).flatMap(configDependencies.getOrElse(_, Nil))
+        val configDeps = extends0
+          .toSeq
+          .sortBy(_.value)
+          .flatMap(configDependencies.getOrElse(_, Nil))
+          .distinct
         val subRes = resolutions(config).subset(configDeps)
 
         val reports = ToSbt.moduleReports(
diff --git a/modules/sbt-coursier/src/main/scala/coursier/sbtcoursier/ResolutionTasks.scala b/modules/sbt-coursier/src/main/scala/coursier/sbtcoursier/ResolutionTasks.scala
index c066a9e0b..89adbbeb9 100644
--- a/modules/sbt-coursier/src/main/scala/coursier/sbtcoursier/ResolutionTasks.scala
+++ b/modules/sbt-coursier/src/main/scala/coursier/sbtcoursier/ResolutionTasks.scala
@@ -2,7 +2,7 @@ package coursier.sbtcoursier
 
 import coursier.ProjectCache
 import coursier.core._
-import coursier.extra.Typelevel
+import coursier.internal.Typelevel
 import coursier.lmcoursier._
 import coursier.lmcoursier.Inputs.withAuthenticationByHost
 import coursier.sbtcoursier.Keys._
@@ -85,7 +85,7 @@ object ResolutionTasks {
 
       val (currentProject, fallbackDependencies, configGraphs) = currentProjectTask.value
 
-      val autoScalaLib = autoScalaLibrary.value
+      val autoScalaLib = autoScalaLibrary.value && scalaModuleInfo.value.forall(_.overrideScalaVersion)
 
       val resolvers = resolversTask.value
 
diff --git a/modules/sbt-coursier/src/sbt-test/shared-1/clean/test b/modules/sbt-coursier/src/sbt-test/shared-1/clean/test
index 6dc6f6976..f2a470ad5 100644
--- a/modules/sbt-coursier/src/sbt-test/shared-1/clean/test
+++ b/modules/sbt-coursier/src/sbt-test/shared-1/clean/test
@@ -1,3 +1,4 @@
+> clean
 > checkEmpty
 > update
 > checkNotEmpty
diff --git a/modules/sbt-coursier/src/sbt-test/shared-1/dotty/LICENSE b/modules/sbt-coursier/src/sbt-test/shared-1/dotty/LICENSE
new file mode 100644
index 000000000..728844ee3
--- /dev/null
+++ b/modules/sbt-coursier/src/sbt-test/shared-1/dotty/LICENSE
@@ -0,0 +1,25 @@
+Copyright (c) 2015 The dotty-example-project contributors.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions
+are met:
+1. Redistributions of source code must retain the above copyright
+   notice, this list of conditions and the following disclaimer.
+2. Redistributions in binary form must reproduce the above copyright
+   notice, this list of conditions and the following disclaimer in the
+   documentation and/or other materials provided with the distribution.
+3. The name of the author may not be used to endorse or promote products
+   derived from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
diff --git a/modules/sbt-coursier/src/sbt-test/shared-1/dotty/README.md b/modules/sbt-coursier/src/sbt-test/shared-1/dotty/README.md
new file mode 100644
index 000000000..e476c5c1d
--- /dev/null
+++ b/modules/sbt-coursier/src/sbt-test/shared-1/dotty/README.md
@@ -0,0 +1 @@
+Cut-n-pasted from https://github.com/lampepfl/dotty-example-project/tree/a753b14e281bbaa6c69f26298913ad6feba969c7
diff --git a/modules/sbt-coursier/src/sbt-test/shared-1/dotty/build.sbt b/modules/sbt-coursier/src/sbt-test/shared-1/dotty/build.sbt
new file mode 100644
index 000000000..e38070b5e
--- /dev/null
+++ b/modules/sbt-coursier/src/sbt-test/shared-1/dotty/build.sbt
@@ -0,0 +1 @@
+scalaVersion := "0.13.0-RC1"
diff --git a/modules/sbt-coursier/src/sbt-test/shared-1/dotty/project/build.properties b/modules/sbt-coursier/src/sbt-test/shared-1/dotty/project/build.properties
new file mode 100644
index 000000000..16dc090c5
--- /dev/null
+++ b/modules/sbt-coursier/src/sbt-test/shared-1/dotty/project/build.properties
@@ -0,0 +1,3 @@
+# sbt-coursier scripted tests: required, as we default to sbt 1.0.3,
+# but sbt-dotty requires sbt >= 1.2.7
+sbt.version=1.2.7
diff --git a/modules/sbt-coursier/src/sbt-test/shared-1/dotty/project/plugins.sbt b/modules/sbt-coursier/src/sbt-test/shared-1/dotty/project/plugins.sbt
new file mode 100644
index 000000000..115463586
--- /dev/null
+++ b/modules/sbt-coursier/src/sbt-test/shared-1/dotty/project/plugins.sbt
@@ -0,0 +1,2 @@
+addSbtPlugin("ch.epfl.lamp" % "sbt-dotty" % "0.3.0")
+addSbtCoursier
diff --git a/modules/sbt-coursier/src/sbt-test/shared-1/dotty/project/project/plugins.sbt b/modules/sbt-coursier/src/sbt-test/shared-1/dotty/project/project/plugins.sbt
new file mode 100644
index 000000000..71a44ffd3
--- /dev/null
+++ b/modules/sbt-coursier/src/sbt-test/shared-1/dotty/project/project/plugins.sbt
@@ -0,0 +1,13 @@
+addSbtPlugin {
+
+  val name = sys.props.getOrElse(
+    "plugin.name",
+    sys.error("plugin.name Java property not set")
+  )
+  val version = sys.props.getOrElse(
+    "plugin.version",
+    sys.error("plugin.version Java property not set")
+  )
+
+  "io.get-coursier" % name % version
+}
\ No newline at end of file
diff --git a/modules/sbt-coursier/src/sbt-test/shared-1/dotty/src/main/scala/Main.scala b/modules/sbt-coursier/src/sbt-test/shared-1/dotty/src/main/scala/Main.scala
new file mode 100644
index 000000000..8a44ae4ef
--- /dev/null
+++ b/modules/sbt-coursier/src/sbt-test/shared-1/dotty/src/main/scala/Main.scala
@@ -0,0 +1,16 @@
+
+object Main {
+
+  def main(args: Array[String]): Unit = {
+
+    runExample("Trait Params")(TraitParams.test)
+
+  }
+
+  private def runExample(name: String)(f: => Unit) = {
+    println(Console.MAGENTA + s"$name example:" + Console.RESET)
+    f
+    println()
+  }
+
+}
diff --git a/modules/sbt-coursier/src/sbt-test/shared-1/dotty/src/main/scala/TraitParams.scala b/modules/sbt-coursier/src/sbt-test/shared-1/dotty/src/main/scala/TraitParams.scala
new file mode 100644
index 000000000..5d4409971
--- /dev/null
+++ b/modules/sbt-coursier/src/sbt-test/shared-1/dotty/src/main/scala/TraitParams.scala
@@ -0,0 +1,21 @@
+/**
+  * Trait Parameters: https://dotty.epfl.ch/docs/reference/other-new-features/trait-parameters.html
+  */
+object TraitParams {
+
+  trait Base(val msg: String)
+  class A extends Base("Hello")
+  class B extends Base("Dotty!")
+
+  // Union types only exist in Dotty, so there's no chance that this will accidentally be compiled with Scala 2
+  private def printMessages(msgs: (A | B)*) = println(msgs.map(_.msg).mkString(" "))
+
+  def test: Unit = {
+
+    printMessages(new A, new B)
+
+    // Sanity check the classpath: this won't run if the dotty jar is not present.
+    val x: Int => Int = z => z
+    x(1)
+  }
+}
diff --git a/modules/sbt-coursier/src/sbt-test/shared-1/dotty/test b/modules/sbt-coursier/src/sbt-test/shared-1/dotty/test
new file mode 100644
index 000000000..62ea636c1
--- /dev/null
+++ b/modules/sbt-coursier/src/sbt-test/shared-1/dotty/test
@@ -0,0 +1 @@
+> run
diff --git a/modules/sbt-coursier/src/sbt-test/shared-1/logger/build.sbt b/modules/sbt-coursier/src/sbt-test/shared-1/logger/build.sbt
index d45af224f..a9c823b68 100644
--- a/modules/sbt-coursier/src/sbt-test/shared-1/logger/build.sbt
+++ b/modules/sbt-coursier/src/sbt-test/shared-1/logger/build.sbt
@@ -7,7 +7,7 @@ coursierCache := baseDirectory.value / "cache"
 logFile := baseDirectory.value / "log"
 
 coursierLogger := {
-  val logStream = new java.io.PrintStream(logFile.value)
+  var logStream: java.io.PrintStream = null
   def log(msg: String): Unit = {
     println(msg)
     logStream.println(msg)
@@ -16,6 +16,9 @@ coursierLogger := {
 
   val logger = new coursier.cache.CacheLogger {
     override def init(sizeHint: Option[Int]): Unit = {
+      logStream = new java.io.PrintStream(
+        new java.io.FileOutputStream(logFile.value, true)
+      )
       log("init")
     }
     override def foundLocally(url: String): Unit = {
@@ -29,6 +32,9 @@ coursierLogger := {
     }
     override def stop(): Unit = {
       log("stop")
+      logStream.flush()
+      logStream.close()
+      logStream = null
     }
   }
 
diff --git a/modules/sbt-coursier/src/sbt-test/shared-1/logger/test b/modules/sbt-coursier/src/sbt-test/shared-1/logger/test
index 157471011..995210423 100644
--- a/modules/sbt-coursier/src/sbt-test/shared-1/logger/test
+++ b/modules/sbt-coursier/src/sbt-test/shared-1/logger/test
@@ -2,5 +2,6 @@ $ delete cache
 > update
 > checkDownloaded
 > reload
+> clean
 > update
 > checkFound
diff --git a/modules/sbt-coursier/src/sbt-test/shared-2/scala-jars/src/main/scala/Main.scala b/modules/sbt-coursier/src/sbt-test/shared-2/scala-jars/src/main/scala/Main.scala
index 43f0726f1..932b548a8 100644
--- a/modules/sbt-coursier/src/sbt-test/shared-2/scala-jars/src/main/scala/Main.scala
+++ b/modules/sbt-coursier/src/sbt-test/shared-2/scala-jars/src/main/scala/Main.scala
@@ -26,7 +26,10 @@ object Main extends App {
     "sbt.global.base",
     sys.props("user.home") + "/.sbt"
   ))
-  val prefix = new File(sbtBase, "boot").getAbsolutePath
+  val prefixes = Seq(new File(sbtBase, "boot").getAbsolutePath) ++
+    Seq("coursier.sbt-launcher.dirs.scala-jars", "coursier.sbt-launcher.dirs.base")
+      .flatMap(sys.props.get(_))
+      .map(new File(_).getAbsolutePath)
 
   def fromBootAndUnique(name: String): Unit = {
     val jars = cp.filter(_.getName.startsWith(name)).distinct
@@ -34,7 +37,7 @@ object Main extends App {
 
     val Seq(jar) = jars
 
-    assert(jar.getAbsolutePath.startsWith(prefix), s"JAR for $name ($jar) not under $prefix")
+    assert(prefixes.exists(jar.getAbsolutePath.startsWith), s"JAR for $name ($jar) not under any of ${prefixes.mkString(", ")}")
   }
 
   val props = Thread.currentThread()
diff --git a/modules/sbt-lm-coursier/src/main/scala/coursier/sbtlmcoursier/LmCoursierPlugin.scala b/modules/sbt-lm-coursier/src/main/scala/coursier/sbtlmcoursier/LmCoursierPlugin.scala
index 9c5c1da1c..857871620 100644
--- a/modules/sbt-lm-coursier/src/main/scala/coursier/sbtlmcoursier/LmCoursierPlugin.scala
+++ b/modules/sbt-lm-coursier/src/main/scala/coursier/sbtlmcoursier/LmCoursierPlugin.scala
@@ -7,7 +7,7 @@ import coursier.sbtcoursiershared.SbtCoursierShared
 import sbt.{AutoPlugin, Classpaths, Def, Setting, Task, taskKey}
 import sbt.Project.inTask
 import sbt.KeyRanks.DTask
-import sbt.Keys.{appConfiguration, autoScalaLibrary, classpathTypes, dependencyResolution, excludeDependencies, scalaBinaryVersion, scalaOrganization, scalaVersion, streams, updateClassifiers, updateSbtClassifiers}
+import sbt.Keys.{appConfiguration, autoScalaLibrary, classpathTypes, dependencyResolution, excludeDependencies, scalaBinaryVersion, scalaModuleInfo, scalaOrganization, scalaVersion, streams, updateClassifiers, updateSbtClassifiers}
 import sbt.librarymanagement.DependencyResolution
 
 object LmCoursierPlugin extends AutoPlugin {
@@ -84,7 +84,7 @@ object LmCoursierPlugin extends AutoPlugin {
           streams.value.log
         )
         val fallbackDeps = coursierFallbackDependencies.value
-        val autoScalaLib = autoScalaLibrary.value
+        val autoScalaLib = autoScalaLibrary.value && scalaModuleInfo.value.forall(_.overrideScalaVersion)
         val profiles = mavenProfiles.value
 
         val authenticationByRepositoryId = coursierCredentials.value.mapValues(_.authentication)
diff --git a/modules/sbt-shading/src/main/scala/coursier/Shading.scala b/modules/sbt-shading/src/main/scala/coursier/Shading.scala
index 77d9b5a63..dfeb45bcc 100644
--- a/modules/sbt-shading/src/main/scala/coursier/Shading.scala
+++ b/modules/sbt-shading/src/main/scala/coursier/Shading.scala
@@ -8,7 +8,7 @@ import com.tonicsystems.jarjar.classpath.ClassPath
 import com.tonicsystems.jarjar.transform.JarTransformer
 import com.tonicsystems.jarjar.transform.config.ClassRename
 import com.tonicsystems.jarjar.transform.jar.DefaultJarProcessor
-import coursier.core.{Configuration, Orders, Type}
+import coursier.core.{Configuration, Orders}
 import sbt.file
 
 object Shading {
diff --git a/modules/sbt-shading/src/main/scala/coursier/ShadingPlugin.scala b/modules/sbt-shading/src/main/scala/coursier/ShadingPlugin.scala
index f27ef8b90..f7412dff3 100644
--- a/modules/sbt-shading/src/main/scala/coursier/ShadingPlugin.scala
+++ b/modules/sbt-shading/src/main/scala/coursier/ShadingPlugin.scala
@@ -2,7 +2,7 @@ package coursier
 
 import java.io.File
 
-import coursier.core.{Configuration, Type}
+import coursier.core.Configuration
 import coursier.ivy.IvyXml.{mappings => ivyXmlMappings}
 import coursier.sbtcoursier.{CoursierPlugin, InputsTasks, Keys}
 import coursier.sbtcoursiershared.{IvyXml, SbtCoursierShared}
diff --git a/project/Settings.scala b/project/Settings.scala
index a06e76ca3..b870c5c7f 100644
--- a/project/Settings.scala
+++ b/project/Settings.scala
@@ -42,7 +42,8 @@ object Settings {
         "-Xmx1024M",
         "-Dplugin.name=" + name.value,
         "-Dplugin.version=" + version.value,
-        "-Dsbttest.base=" + (sourceDirectory.value / "sbt-test").getAbsolutePath
+        "-Dsbttest.base=" + (sourceDirectory.value / "sbt-test").getAbsolutePath,
+        "-Dcoursier.sbt-launcher.add-plugin=false"
       ),
       scriptedBufferLog := false,
       sbtPlugin := true,
diff --git a/scripts/travis.sh b/scripts/travis.sh
index b45bd8a02..55382af60 100755
--- a/scripts/travis.sh
+++ b/scripts/travis.sh
@@ -1,12 +1,6 @@
 #!/usr/bin/env bash
 set -euvx
 
-downloadInstallSbtExtras() {
-  mkdir -p bin
-  curl -L -o bin/sbt https://github.com/paulp/sbt-extras/raw/9ade5fa54914ca8aded44105bf4b9a60966f3ccd/sbt
-  chmod +x bin/sbt
-}
-
 lmCoursier() {
   [ "${LM_COURSIER:-""}" = 1 ]
 }
@@ -55,8 +49,6 @@ addPgpKeys() {
 }
 
 
-downloadInstallSbtExtras
-
 if sbtShading; then
   runSbtShadingTests
 elif sbtPgpCoursier; then