diff --git a/build.sbt b/build.sbt
index 3fd808f3c..a7d28fc97 100644
--- a/build.sbt
+++ b/build.sbt
@@ -219,6 +219,7 @@ lazy val cli = project
   .settings(commonSettings)
   .settings(noPublish210Settings)
   .settings(packAutoSettings)
+  .settings(proguardSettings)
   .settings(
     name := "coursier-cli",
     libraryDependencies ++= {
@@ -229,7 +230,15 @@ lazy val cli = project
     },
     resourceGenerators in Compile += packageBin.in(bootstrap).in(Compile).map { jar =>
       Seq(jar)
-    }.taskValue
+    }.taskValue,
+    ProguardKeys.proguardVersion in Proguard := "5.2.1",
+    ProguardKeys.options in Proguard ++= Seq(
+      "-dontwarn",
+      "-keep class coursier.cli.Coursier {\n  public static void main(java.lang.String[]);\n}",
+      "-keep class coursier.cli.IsolatedClassLoader {\n  public java.lang.String[] getIsolationTargets();\n}"
+    ),
+    javaOptions in (Proguard, ProguardKeys.proguard) := Seq("-Xmx3172M"),
+    artifactPath in Proguard := (ProguardKeys.proguardDirectory in Proguard).value / "coursier-standalone.jar"
   )
 
 lazy val web = project
diff --git a/cache/src/main/scala/coursier/Cache.scala b/cache/src/main/scala/coursier/Cache.scala
index af10e8168..846828393 100644
--- a/cache/src/main/scala/coursier/Cache.scala
+++ b/cache/src/main/scala/coursier/Cache.scala
@@ -357,8 +357,8 @@ object Cache {
       artifact0.checksumUrls.get(sumType) match {
         case Some(sumFile) =>
           Task {
-            val sum = scala.io.Source.fromFile(sumFile)
-              .getLines()
+            val sum = new String(NioFiles.readAllBytes(new File(sumFile).toPath), "UTF-8")
+              .linesIterator
               .toStream
               .headOption
               .mkString
@@ -471,7 +471,7 @@ object Cache {
         pool = pool
       ).leftMap(_.message).map { f =>
         // FIXME Catch error here?
-        scala.io.Source.fromFile(f)("UTF-8").mkString
+        new String(NioFiles.readAllBytes(f.toPath), "UTF-8")
       }
   }
 
@@ -571,31 +571,29 @@ object Cache {
 
 }
 
-sealed trait FileError extends Product with Serializable {
-  def message: String
-}
+sealed abstract class FileError(val message: String) extends Product with Serializable
 
 object FileError {
 
-  case class DownloadError(message0: String) extends FileError {
-    def message = s"Download error: $message0"
-  }
-  case class NotFound(file: String) extends FileError {
-    def message = s"Not found: $file"
-  }
-  case class ChecksumNotFound(sumType: String, file: String) extends FileError {
-    def message = s"$sumType checksum not found: $file"
-  }
-  case class WrongChecksum(sumType: String, got: String, expected: String, file: String, sumFile: String) extends FileError {
-    def message = s"$sumType checksum validation failed: $file"
-  }
+  final case class DownloadError(reason: String) extends FileError(s"Download error: $reason")
 
-  sealed trait Recoverable extends FileError
-  case class Locked(file: File) extends Recoverable {
-    def message = s"Locked: $file"
-  }
-  case class ConcurrentDownload(url: String) extends Recoverable {
-    def message = s"Concurrent download: $url"
-  }
+  final case class NotFound(file: String) extends FileError(s"Not found: $file")
+
+  final case class ChecksumNotFound(
+    sumType: String,
+    file: String
+  ) extends FileError(s"$sumType checksum not found: $file")
+
+  final case class WrongChecksum(
+    sumType: String,
+    got: String,
+    expected: String,
+    file: String,
+    sumFile: String
+  ) extends FileError(s"$sumType checksum validation failed: $file")
+
+  sealed abstract class Recoverable(message: String) extends FileError(message)
+  final case class Locked(file: File) extends Recoverable(s"Locked: $file")
+  final case class ConcurrentDownload(url: String) extends Recoverable(s"Concurrent download: $url")
 
 }
diff --git a/cache/src/main/scala/coursier/CachePolicy.scala b/cache/src/main/scala/coursier/CachePolicy.scala
index 0bf51e6e3..2e739640a 100644
--- a/cache/src/main/scala/coursier/CachePolicy.scala
+++ b/cache/src/main/scala/coursier/CachePolicy.scala
@@ -1,6 +1,6 @@
 package coursier
 
-sealed trait CachePolicy extends Product with Serializable
+sealed abstract class CachePolicy extends Product with Serializable
 
 object CachePolicy {
   case object LocalOnly extends CachePolicy
diff --git a/cli/src/main/scala-2.11/coursier/cli/Coursier.scala b/cli/src/main/scala-2.11/coursier/cli/Coursier.scala
index 64db345eb..d1a8af958 100644
--- a/cli/src/main/scala-2.11/coursier/cli/Coursier.scala
+++ b/cli/src/main/scala-2.11/coursier/cli/Coursier.scala
@@ -62,7 +62,7 @@ case class CacheOptions(
     cache: String = Cache.defaultBase.toString
 )
 
-sealed trait CoursierCommand extends Command
+sealed abstract class CoursierCommand extends Command
 
 case class Resolve(
   @Recurse
diff --git a/core/shared/src/main/scala/coursier/core/Definitions.scala b/core/shared/src/main/scala/coursier/core/Definitions.scala
index 57a7c6c69..f178a0cab 100644
--- a/core/shared/src/main/scala/coursier/core/Definitions.scala
+++ b/core/shared/src/main/scala/coursier/core/Definitions.scala
@@ -9,7 +9,7 @@ package coursier.core
  *
  * Using the same terminology as Ivy.
  */
-case class Module(
+final case class Module(
   organization: String,
   name: String,
   attributes: Map[String, String]
@@ -28,6 +28,8 @@ case class Module(
   override def toString =
     s"$organization:$name" +
     (if (attributes.nonEmpty) s";$attributesStr" else "")
+
+  override final lazy val hashCode = Module.unapply(this).get.hashCode()
 }
 
 /**
@@ -36,7 +38,7 @@ case class Module(
  * The remaining fields are left untouched, some being transitively
  * propagated (exclusions, optional, in particular).
  */
-case class Dependency(
+final case class Dependency(
   module: Module,
   version: String,
   configuration: String,
@@ -48,11 +50,13 @@ case class Dependency(
 
   transitive: Boolean
 ) {
-  def moduleVersion = (module, version)
+  lazy val moduleVersion = (module, version)
+
+  override lazy val hashCode = Dependency.unapply(this).get.hashCode()
 }
 
 // Maven-specific
-case class Attributes(
+final case class Attributes(
   `type`: String,
   classifier: String
 ) {
@@ -60,7 +64,7 @@ case class Attributes(
     Publication(name, `type`, ext, classifier)
 }
 
-case class Project(
+final case class Project(
   module: Module,
   version: String,
   // First String is configuration (scope for Maven)
@@ -83,7 +87,7 @@ case class Project(
   // Extra infos, not used during resolution
   info: Info
 ) {
-  def moduleVersion = (module, version)
+  lazy val moduleVersion = (module, version)
 
   /** All configurations that each configuration extends, including the ones it extends transitively */
   lazy val allConfigurations: Map[String, Set[String]] =
@@ -91,7 +95,7 @@ case class Project(
 }
 
 /** Extra project info, not used during resolution */
-case class Info(
+final case class Info(
   description: String,
   homePage: String,
   licenses: Seq[(String, Option[String])],
@@ -100,7 +104,7 @@ case class Info(
 )
 
 object Info {
-  case class Developer(
+  final case class Developer(
     id: String,
     name: String,
     url: String
@@ -110,10 +114,10 @@ object Info {
 }
 
 // Maven-specific
-case class Activation(properties: Seq[(String, Option[String])])
+final case class Activation(properties: Seq[(String, Option[String])])
 
 // Maven-specific
-case class Profile(
+final case class Profile(
   id: String,
   activeByDefault: Option[Boolean],
   activation: Activation,
@@ -123,7 +127,7 @@ case class Profile(
 )
 
 // Maven-specific
-case class Versions(
+final case class Versions(
   latest: String,
   release: String,
   available: List[String],
@@ -131,7 +135,7 @@ case class Versions(
 )
 
 object Versions {
-  case class DateTime(
+  final case class DateTime(
     year: Int,
     month: Int,
     day: Int,
@@ -142,7 +146,7 @@ object Versions {
 }
 
 // Maven-specific
-case class SnapshotVersion(
+final case class SnapshotVersion(
   classifier: String,
   extension: String,
   value: String,
@@ -150,7 +154,7 @@ case class SnapshotVersion(
 )
 
 // Maven-specific
-case class SnapshotVersioning(
+final case class SnapshotVersioning(
   module: Module,
   version: String,
   latest: String,
@@ -163,7 +167,7 @@ case class SnapshotVersioning(
 )
 
 // Ivy-specific
-case class Publication(
+final case class Publication(
   name: String,
   `type`: String,
   ext: String,
@@ -172,7 +176,7 @@ case class Publication(
   def attributes: Attributes = Attributes(`type`, classifier)
 }
 
-case class Artifact(
+final case class Artifact(
   url: String,
   checksumUrls: Map[String, String],
   extra: Map[String, Artifact],
diff --git a/core/shared/src/main/scala/coursier/core/Resolution.scala b/core/shared/src/main/scala/coursier/core/Resolution.scala
index ed3304d5e..8a2eb6b28 100644
--- a/core/shared/src/main/scala/coursier/core/Resolution.scala
+++ b/core/shared/src/main/scala/coursier/core/Resolution.scala
@@ -1,9 +1,10 @@
 package coursier.core
 
+import java.util.concurrent.ConcurrentHashMap
 import java.util.regex.Pattern.quote
 
 import scala.annotation.tailrec
-import scala.collection.mutable
+import scala.collection.JavaConverters._
 import scalaz.{ \/-, -\/ }
 
 object Resolution {
@@ -76,7 +77,7 @@ object Resolution {
   def substituteProps(s: String, properties: Map[String, String]) = {
     val matches = propRegex
       .findAllMatchIn(s)
-      .toList
+      .toVector
       .reverse
 
     if (matches.isEmpty) s
@@ -172,7 +173,7 @@ object Resolution {
   ): (Seq[Dependency], Seq[Dependency], Map[Module, String]) = {
 
     val mergedByModVer = dependencies
-      .toList
+      .toVector
       .groupBy(dep => dep.module)
       .map { case (module, deps) =>
         module -> {
@@ -203,7 +204,7 @@ object Resolution {
 
     val merged = mergedByModVer
       .values
-      .toList
+      .toVector
 
     (
       merged
@@ -424,35 +425,60 @@ object Resolution {
  * @param projectCache: cache of known projects
  * @param errorCache: keeps track of the modules whose project definition could not be found
  */
-case class Resolution(
+final case class Resolution(
   rootDependencies: Set[Dependency],
   dependencies: Set[Dependency],
   forceVersions: Map[Module, String],
   conflicts: Set[Dependency],
   projectCache: Map[Resolution.ModuleVersion, (Artifact.Source, Project)],
   errorCache: Map[Resolution.ModuleVersion, Seq[String]],
+  finalDependenciesCache: Map[Dependency, Seq[Dependency]],
   filter: Option[Dependency => Boolean],
   profileActivation: Option[(String, Activation, Map[String, String]) => Boolean]
 ) {
 
+  def copyWithCache(
+    rootDependencies: Set[Dependency] = rootDependencies,
+    dependencies: Set[Dependency] = dependencies,
+    forceVersions: Map[Module, String] = forceVersions,
+    conflicts: Set[Dependency] = conflicts,
+    projectCache: Map[Resolution.ModuleVersion, (Artifact.Source, Project)] = projectCache,
+    errorCache: Map[Resolution.ModuleVersion, Seq[String]] = errorCache,
+    filter: Option[Dependency => Boolean] = filter,
+    profileActivation: Option[(String, Activation, Map[String, String]) => Boolean] = profileActivation
+  ): Resolution =
+    copy(
+      rootDependencies,
+      dependencies,
+      forceVersions,
+      conflicts,
+      projectCache,
+      errorCache,
+      finalDependenciesCache ++ finalDependenciesCache0.asScala,
+      filter,
+      profileActivation
+    )
+
   import Resolution._
 
-  private val finalDependenciesCache =
-    new mutable.HashMap[Dependency, Seq[Dependency]]()
-  private def finalDependencies0(dep: Dependency) =
-    finalDependenciesCache.synchronized {
-      finalDependenciesCache.getOrElseUpdate(dep, {
-        if (dep.transitive)
-          projectCache.get(dep.moduleVersion) match {
-            case Some((_, proj)) =>
-              finalDependencies(dep, proj)
-                .filter(filter getOrElse defaultFilter)
-            case None => Nil
-          }
-        else
-          Nil
-      })
-    }
+  private[core] val finalDependenciesCache0 = new ConcurrentHashMap[Dependency, Seq[Dependency]]
+
+  private def finalDependencies0(dep: Dependency): Seq[Dependency] =
+    if (dep.transitive) {
+      val deps = finalDependenciesCache.getOrElse(dep, finalDependenciesCache0.get(dep))
+
+      if (deps == null)
+        projectCache.get(dep.moduleVersion) match {
+          case Some((_, proj)) =>
+            val res = finalDependencies(dep, proj).filter(filter getOrElse defaultFilter)
+            finalDependenciesCache0.put(dep, res)
+            res
+          case None => Nil
+        }
+      else
+        deps
+    } else
+      Nil
 
   /**
    * Transitive dependencies of the current dependencies, according to
@@ -460,9 +486,9 @@ case class Resolution(
    *
    * No attempt is made to solve version conflicts here.
    */
-  def transitiveDependencies: Seq[Dependency] =
+  lazy val transitiveDependencies: Seq[Dependency] =
     (dependencies -- conflicts)
-      .toList
+      .toVector
       .flatMap(finalDependencies0)
 
   /**
@@ -476,7 +502,7 @@ case class Resolution(
    * Returns a tuple made of the conflicting dependencies, all
    * the dependencies, and the retained version of each module.
    */
-  def nextDependenciesAndConflicts: (Seq[Dependency], Seq[Dependency], Map[Module, String]) =
+  lazy val nextDependenciesAndConflicts: (Seq[Dependency], Seq[Dependency], Map[Module, String]) =
     // TODO Provide the modules whose version was forced by dependency overrides too
     merge(
       rootDependencies.map(withDefaultConfig) ++ dependencies ++ transitiveDependencies,
@@ -486,7 +512,7 @@ case class Resolution(
   /**
    * The modules we miss some info about.
    */
-  def missingFromCache: Set[ModuleVersion] = {
+  lazy val missingFromCache: Set[ModuleVersion] = {
     val modules = dependencies
       .map(_.moduleVersion)
     val nextModules = nextDependenciesAndConflicts._2
@@ -500,7 +526,7 @@ case class Resolution(
   /**
    * Whether the resolution is done.
    */
-  def isDone: Boolean = {
+  lazy val isDone: Boolean = {
     def isFixPoint = {
       val (nextConflicts, _, _) = nextDependenciesAndConflicts
 
@@ -520,7 +546,7 @@ case class Resolution(
    *
    * The versions of all the dependencies returned are erased (emptied).
    */
-  def reverseDependencies: Map[Dependency, Vector[Dependency]] = {
+  lazy val reverseDependencies: Map[Dependency, Vector[Dependency]] = {
     val (updatedConflicts, updatedDeps, _) = nextDependenciesAndConflicts
 
     val trDepsSeq =
@@ -546,7 +572,7 @@ case class Resolution(
    *
    * The versions of all the dependencies returned are erased (emptied).
    */
-  def remainingDependencies: Set[Dependency] = {
+  lazy val remainingDependencies: Set[Dependency] = {
     val rootDependencies0 = rootDependencies
       .map(withDefaultConfig)
       .map(eraseVersion)
@@ -568,7 +594,7 @@ case class Resolution(
               broughtBy
                 .filter(x => remaining.contains(x) || rootDependencies0(x))
             )
-            .toList
+            .toVector
             .toMap
         )
     }
@@ -581,7 +607,7 @@ case class Resolution(
   /**
    * The final next dependency set, stripped of no more required ones.
    */
-  def newDependencies: Set[Dependency] = {
+  lazy val newDependencies: Set[Dependency] = {
     val remainingDependencies0 = remainingDependencies
 
     nextDependenciesAndConflicts._2
@@ -589,10 +615,10 @@ case class Resolution(
       .toSet
   }
 
-  private def nextNoMissingUnsafe: Resolution = {
+  private lazy val nextNoMissingUnsafe: Resolution = {
     val (newConflicts, _, _) = nextDependenciesAndConflicts
 
-    copy(
+    copyWithCache(
       dependencies = newDependencies ++ newConflicts,
       conflicts = newConflicts.toSet
     )
@@ -856,7 +882,7 @@ case class Resolution(
         newDeps
     }
 
-    copy(
+    copyWithCache(
       rootDependencies = dependencies,
       dependencies = helper(dependencies.map(updateVersion))
       // don't know if something should be done about conflicts
diff --git a/core/shared/src/main/scala/coursier/core/ResolutionProcess.scala b/core/shared/src/main/scala/coursier/core/ResolutionProcess.scala
index 4ea83f9d0..8d6f3b43f 100644
--- a/core/shared/src/main/scala/coursier/core/ResolutionProcess.scala
+++ b/core/shared/src/main/scala/coursier/core/ResolutionProcess.scala
@@ -5,7 +5,7 @@ import scalaz._
 import scala.annotation.tailrec
 
 
-sealed trait ResolutionProcess {
+sealed abstract class ResolutionProcess {
   def run[F[_]](
     fetch: Fetch.Metadata[F],
     maxIterations: Int = 50
@@ -52,7 +52,7 @@ sealed trait ResolutionProcess {
   def current: Resolution
 }
 
-case class Missing(
+final case class Missing(
   missing: Seq[(Module, String)],
   current: Resolution,
   cont: Resolution => ResolutionProcess
@@ -74,7 +74,7 @@ case class Missing(
     def cont0(res: Resolution) = {
       val res0 =
         successes.foldLeft(res){case (acc, (modVer, (source, proj))) =>
-          acc.copy(projectCache = acc.projectCache + (
+          acc.copyWithCache(projectCache = acc.projectCache + (
             modVer -> (source, acc.withDependencyManagement(proj))
           ))
         }
@@ -83,7 +83,7 @@ case class Missing(
     }
 
     val current0 = current
-      .copy(errorCache = current.errorCache ++ errors)
+      .copyWithCache(errorCache = current.errorCache ++ errors)
 
     if (depMgmtMissing.isEmpty)
       cont0(current0)
@@ -93,7 +93,7 @@ case class Missing(
 
 }
 
-case class Continue(
+final case class Continue(
   current: Resolution,
   cont: Resolution => ResolutionProcess
 ) extends ResolutionProcess {
@@ -108,7 +108,7 @@ case class Continue(
 
 }
 
-case class Done(resolution: Resolution) extends ResolutionProcess {
+final case class Done(resolution: Resolution) extends ResolutionProcess {
   def current: Resolution = resolution
 }
 
diff --git a/core/shared/src/main/scala/coursier/core/Version.scala b/core/shared/src/main/scala/coursier/core/Version.scala
index b15d3f9ff..34da4d71d 100644
--- a/core/shared/src/main/scala/coursier/core/Version.scala
+++ b/core/shared/src/main/scala/coursier/core/Version.scala
@@ -20,7 +20,7 @@ case class Version(repr: String) extends Ordered[Version] {
 
 object Version {
 
-  sealed trait Item extends Ordered[Item] {
+  sealed abstract class Item extends Ordered[Item] {
     def compare(other: Item): Int =
       (this, other) match {
         case (Number(a), Number(b)) => a.compare(b)
@@ -43,27 +43,27 @@ object Version {
     def compareToEmpty: Int = 1
   }
 
-  sealed trait Numeric extends Item {
+  sealed abstract class Numeric extends Item {
     def repr: String
     def next: Numeric
   }
-  case class Number(value: Int) extends Numeric {
+  final case class Number(value: Int) extends Numeric {
     val order = 0
     def next: Number = Number(value + 1)
     def repr: String = value.toString
     override def compareToEmpty = value.compare(0)
   }
-  case class BigNumber(value: BigInt) extends Numeric {
+  final case class BigNumber(value: BigInt) extends Numeric {
     val order = 0
     def next: BigNumber = BigNumber(value + 1)
     def repr: String = value.toString
     override def compareToEmpty = value.compare(0)
   }
-  case class Qualifier(value: String, level: Int) extends Item {
+  final case class Qualifier(value: String, level: Int) extends Item {
     val order = -2
     override def compareToEmpty = level.compare(0)
   }
-  case class Literal(value: String) extends Item {
+  final case class Literal(value: String) extends Item {
     val order = -1
     override def compareToEmpty = if (value.isEmpty) 0 else 1
   }
@@ -93,7 +93,7 @@ object Version {
   val qualifiersMap = qualifiers.map(q => q.value -> q).toMap
 
   object Tokenizer {
-    sealed trait Separator
+    sealed abstract class Separator
     case object Dot extends Separator
     case object Hyphen extends Separator
     case object Underscore extends Separator
diff --git a/core/shared/src/main/scala/coursier/core/Versions.scala b/core/shared/src/main/scala/coursier/core/Versions.scala
index ae4877200..5398f262c 100644
--- a/core/shared/src/main/scala/coursier/core/Versions.scala
+++ b/core/shared/src/main/scala/coursier/core/Versions.scala
@@ -82,21 +82,23 @@ object VersionInterval {
   val zero = VersionInterval(None, None, fromIncluded = false, toIncluded = false)
 }
 
-sealed trait VersionConstraint {
-  def interval: VersionInterval
-  def repr: String
-}
+sealed abstract class VersionConstraint(
+  val interval: VersionInterval,
+  val repr: String
+)
+
 object VersionConstraint {
   /** Currently treated as minimum... */
-  case class Preferred(version: Version) extends VersionConstraint {
-    def interval: VersionInterval = VersionInterval(Some(version), Option.empty, fromIncluded = true, toIncluded = false)
-    def repr: String = version.repr
-  }
-  case class Interval(interval: VersionInterval) extends VersionConstraint {
-    def repr: String = interval.repr
-  }
-  case object None extends VersionConstraint {
-    val interval = VersionInterval.zero
-    def repr: String = "" // Once parsed, "(,)" becomes "" because of this
-  }
-}
\ No newline at end of file
+  final case class Preferred(version: Version) extends VersionConstraint(
+    VersionInterval(Some(version), Option.empty, fromIncluded = true, toIncluded = false),
+    version.repr
+  )
+  final case class Interval(interval0: VersionInterval) extends VersionConstraint(
+    interval0,
+    interval0.repr
+  )
+  case object None extends VersionConstraint(
+    VersionInterval.zero,
+    "" // Once parsed, "(,)" becomes "" because of this
+  )
+}
diff --git a/core/shared/src/main/scala/coursier/ivy/Pattern.scala b/core/shared/src/main/scala/coursier/ivy/Pattern.scala
index 5054bd6dc..820fad6d0 100644
--- a/core/shared/src/main/scala/coursier/ivy/Pattern.scala
+++ b/core/shared/src/main/scala/coursier/ivy/Pattern.scala
@@ -23,7 +23,7 @@ object Pattern {
     def apply(content: String): Map[String, String] => String \/ String
   }
   object PatternPart {
-    case class Literal(override val effectiveStart: Int, override val effectiveEnd: Int) extends PatternPart(effectiveStart, effectiveEnd) {
+    final case class Literal(override val effectiveStart: Int, override val effectiveEnd: Int) extends PatternPart(effectiveStart, effectiveEnd) {
       def apply(content: String): Map[String, String] => String \/ String = {
         assert(content.length == effectiveEnd - effectiveStart)
         val matches = variableRegex.findAllMatchIn(content).toList
@@ -54,7 +54,7 @@ object Pattern {
           helper(0, matches, new StringBuilder)
       }
     }
-    case class Optional(start0: Int, end0: Int) extends PatternPart(start0 + 1, end0 - 1) {
+    final case class Optional(start0: Int, end0: Int) extends PatternPart(start0 + 1, end0 - 1) {
       override def start = start0
       override def end = end0
 
@@ -78,7 +78,7 @@ object Pattern {
 
 }
 
-case class Pattern(
+final case class Pattern(
   pattern: String,
   properties: Map[String, String]
 ) {
diff --git a/core/shared/src/main/scala/coursier/package.scala b/core/shared/src/main/scala/coursier/package.scala
index d15ba3985..15ab6efb4 100644
--- a/core/shared/src/main/scala/coursier/package.scala
+++ b/core/shared/src/main/scala/coursier/package.scala
@@ -70,6 +70,7 @@ package object coursier {
       conflicts: Set[Dependency] = Set.empty,
       projectCache: Map[ModuleVersion, (Artifact.Source, Project)] = Map.empty,
       errorCache: Map[ModuleVersion, Seq[String]] = Map.empty,
+      finalDependencies: Map[Dependency, Seq[Dependency]] = Map.empty,
       filter: Option[Dependency => Boolean] = None,
       profileActivation: Option[(String, core.Activation, Map[String, String]) => Boolean] = None
     ): Resolution =
@@ -80,6 +81,7 @@ package object coursier {
         conflicts,
         projectCache,
         errorCache,
+        finalDependencies,
         filter,
         profileActivation
       )
diff --git a/core/shared/src/main/scala/coursier/util/Properties.scala b/core/shared/src/main/scala/coursier/util/Properties.scala
index 365c182ea..d521c1ed7 100644
--- a/core/shared/src/main/scala/coursier/util/Properties.scala
+++ b/core/shared/src/main/scala/coursier/util/Properties.scala
@@ -1,11 +1,11 @@
 package coursier.util
 
-import java.util.Properties
+import java.util.{ Properties => JProperties }
 
 object Properties {
 
   private lazy val props = {
-    val p = new Properties()
+    val p = new JProperties()
     p.load(
       getClass
         .getClassLoader
diff --git a/coursier-standalone b/coursier-standalone
index 5419cf784..14c18fecb 100755
Binary files a/coursier-standalone and b/coursier-standalone differ
diff --git a/project/generate-standalone-launcher.sh b/project/generate-standalone-launcher.sh
index 791e9f2d6..2109a34f3 100755
--- a/project/generate-standalone-launcher.sh
+++ b/project/generate-standalone-launcher.sh
@@ -23,6 +23,10 @@ cat >> coursier.pro << EOF
 -keep class coursier.cli.Coursier {
   public static void main(java.lang.String[]);
 }
+
+-keep class coursier.cli.IsolatedClassLoader {
+  public java.lang.String[] getIsolationTargets();
+}
 EOF
 
 # -noverify added in launcher below because of errors like
diff --git a/project/plugins.sbt b/project/plugins.sbt
index 0d8c0281b..3e1a804b9 100644
--- a/project/plugins.sbt
+++ b/project/plugins.sbt
@@ -4,3 +4,4 @@ addSbtPlugin("com.jsuereth" % "sbt-pgp" % "1.0.0")
 addSbtPlugin("org.scoverage" % "sbt-scoverage" % "1.1.0")
 addSbtPlugin("org.tpolecat" % "tut-plugin" % "0.4.0")
 addSbtPlugin("com.github.alexarchambault" % "coursier-sbt-plugin" % "1.0.0-M4")
+addSbtPlugin("com.typesafe.sbt" % "sbt-proguard" % "0.2.2")
diff --git a/tests/shared/src/test/scala/coursier/test/CentralTests.scala b/tests/shared/src/test/scala/coursier/test/CentralTests.scala
index db05027ee..76ef8b9ac 100644
--- a/tests/shared/src/test/scala/coursier/test/CentralTests.scala
+++ b/tests/shared/src/test/scala/coursier/test/CentralTests.scala
@@ -90,8 +90,7 @@ object CentralTests extends TestSuite {
     'logback{
       async {
         val dep = Dependency(Module("ch.qos.logback", "logback-classic"), "1.1.3")
-        val res = await(resolve(Set(dep)))
-          .copy(projectCache = Map.empty, errorCache = Map.empty) // No validating these here
+        val res = await(resolve(Set(dep))).clearCaches
 
         val expected = Resolution(
           rootDependencies = Set(dep),
@@ -106,8 +105,7 @@ object CentralTests extends TestSuite {
     'asm{
       async {
         val dep = Dependency(Module("org.ow2.asm", "asm-commons"), "5.0.2")
-        val res = await(resolve(Set(dep)))
-          .copy(projectCache = Map.empty, errorCache = Map.empty) // No validating these here
+        val res = await(resolve(Set(dep))).clearCaches
 
         val expected = Resolution(
           rootDependencies = Set(dep),
@@ -123,7 +121,7 @@ object CentralTests extends TestSuite {
       async {
         val dep = Dependency(Module("joda-time", "joda-time"), "[2.2,2.8]")
         val res0 = await(resolve(Set(dep)))
-        val res = res0.copy(projectCache = Map.empty, errorCache = Map.empty)
+        val res = res0.clearCaches
 
         val expected = Resolution(
           rootDependencies = Set(dep),
diff --git a/tests/shared/src/test/scala/coursier/test/ResolutionTests.scala b/tests/shared/src/test/scala/coursier/test/ResolutionTests.scala
index c83a9ddd5..a47c54967 100644
--- a/tests/shared/src/test/scala/coursier/test/ResolutionTests.scala
+++ b/tests/shared/src/test/scala/coursier/test/ResolutionTests.scala
@@ -203,7 +203,7 @@ object ResolutionTests extends TestSuite {
         val dep = Dependency(Module("acme", "config"), "1.3.0")
         val res = await(resolve0(
           Set(dep)
-        ))
+        )).clearFinalDependenciesCache
 
         val expected = Resolution(
           rootDependencies = Set(dep),
@@ -220,7 +220,7 @@ object ResolutionTests extends TestSuite {
         val trDep = Dependency(Module("acme", "play-json"), "2.4.0")
         val res = await(resolve0(
           Set(dep)
-        ))
+        )).clearFinalDependenciesCache
 
         val expected = Resolution(
           rootDependencies = Set(dep),
@@ -243,7 +243,7 @@ object ResolutionTests extends TestSuite {
         )
         val res = await(resolve0(
           Set(dep)
-        )).copy(filter = None, projectCache = Map.empty)
+        )).clearCaches
 
         val expected = Resolution(
           rootDependencies = Set(dep),
@@ -264,7 +264,7 @@ object ResolutionTests extends TestSuite {
         )
         val res = await(resolve0(
           Set(dep)
-        )).copy(filter = None, projectCache = Map.empty)
+        )).clearCaches
 
         val expected = Resolution(
           rootDependencies = Set(dep),
@@ -285,7 +285,7 @@ object ResolutionTests extends TestSuite {
         )
         val res = await(resolve0(
           Set(dep)
-        )).copy(filter = None, projectCache = Map.empty)
+        )).clearCaches
 
         val expected = Resolution(
           rootDependencies = Set(dep),
@@ -300,7 +300,7 @@ object ResolutionTests extends TestSuite {
         val dep = Dependency(Module("hudsucker", "mail"), "10.0")
         val res = await(resolve0(
           Set(dep)
-        )).copy(filter = None, projectCache = Map.empty)
+        )).clearCaches
 
         val expected = Resolution(
           rootDependencies = Set(dep),
@@ -319,7 +319,7 @@ object ResolutionTests extends TestSuite {
         )
         val res = await(resolve0(
           Set(dep)
-        )).copy(filter = None, projectCache = Map.empty)
+        )).clearCaches
 
         val expected = Resolution(
           rootDependencies = Set(dep),
@@ -337,7 +337,7 @@ object ResolutionTests extends TestSuite {
           Dependency(Module("org.gnome", "desktop"), "7.0"))
         val res = await(resolve0(
           Set(dep)
-        )).copy(filter = None, projectCache = Map.empty, errorCache = Map.empty)
+        )).clearCaches
 
         val expected = Resolution(
           rootDependencies = Set(dep),
@@ -354,7 +354,7 @@ object ResolutionTests extends TestSuite {
           Dependency(Module("gov.nsa", "secure-pgp"), "10.0", exclusions = Set(("*", "crypto"))))
         val res = await(resolve0(
           Set(dep)
-        )).copy(filter = None, projectCache = Map.empty, errorCache = Map.empty)
+        )).clearCaches
 
         val expected = Resolution(
           rootDependencies = Set(dep),
@@ -369,7 +369,7 @@ object ResolutionTests extends TestSuite {
         val dep = Dependency(Module("com.thoughtworks.paranamer", "paranamer"), "2.6")
         val res = await(resolve0(
           Set(dep)
-        )).copy(filter = None, projectCache = Map.empty, errorCache = Map.empty)
+        )).clearCaches
 
         val expected = Resolution(
           rootDependencies = Set(dep),
@@ -386,7 +386,7 @@ object ResolutionTests extends TestSuite {
           Dependency(Module("org.escalier", "librairie-standard"), "2.11.6"))
         val res = await(resolve0(
           Set(dep)
-        )).copy(filter = None, projectCache = Map.empty, errorCache = Map.empty)
+        )).clearCaches
 
         val expected = Resolution(
           rootDependencies = Set(dep),
@@ -405,7 +405,7 @@ object ResolutionTests extends TestSuite {
               Dependency(Module("org.escalier", "librairie-standard"), "2.11.6"))
             val res = await(resolve0(
               Set(dep)
-            )).copy(filter = None, projectCache = Map.empty, errorCache = Map.empty)
+            )).clearCaches
 
             val expected = Resolution(
               rootDependencies = Set(dep),
@@ -426,7 +426,7 @@ object ResolutionTests extends TestSuite {
           Dependency(Module("org.escalier", "librairie-standard"), "2.11.6"))
         val res = await(resolve0(
           Set(dep)
-        )).copy(filter = None, projectCache = Map.empty, errorCache = Map.empty)
+        )).clearCaches
 
         val expected = Resolution(
           rootDependencies = Set(dep),
@@ -447,7 +447,7 @@ object ResolutionTests extends TestSuite {
         val res = await(resolve0(
           Set(dep),
           filter = Some(_ => true)
-        )).copy(filter = None, projectCache = Map.empty, errorCache = Map.empty)
+        )).clearCaches.clearFilter
 
         val expected = Resolution(
           rootDependencies = Set(dep),
@@ -470,7 +470,7 @@ object ResolutionTests extends TestSuite {
         val res = await(resolve0(
           deps,
           filter = Some(_ => true)
-        )).copy(filter = None, projectCache = Map.empty, errorCache = Map.empty)
+        )).clearCaches.clearFilter
 
         val expected = Resolution(
           rootDependencies = deps,
@@ -492,7 +492,7 @@ object ResolutionTests extends TestSuite {
           val res = await(resolve0(
             deps,
             forceVersions = depOverrides
-          )).copy(filter = None, projectCache = Map.empty, errorCache = Map.empty)
+          )).clearCaches
 
           val expected = Resolution(
             rootDependencies = deps,
@@ -516,7 +516,7 @@ object ResolutionTests extends TestSuite {
           val res = await(resolve0(
             deps,
             forceVersions = depOverrides
-          )).copy(filter = None, projectCache = Map.empty, errorCache = Map.empty)
+          )).clearCaches
 
           val expected = Resolution(
             rootDependencies = deps,
@@ -542,7 +542,7 @@ object ResolutionTests extends TestSuite {
           val res = await(resolve0(
             deps,
             forceVersions = depOverrides
-          )).copy(filter = None, projectCache = Map.empty, errorCache = Map.empty)
+          )).clearCaches
 
           val expected = Resolution(
             rootDependencies = deps,
diff --git a/tests/shared/src/test/scala/coursier/test/package.scala b/tests/shared/src/test/scala/coursier/test/package.scala
index 30fa8f3ea..7fe13dce0 100644
--- a/tests/shared/src/test/scala/coursier/test/package.scala
+++ b/tests/shared/src/test/scala/coursier/test/package.scala
@@ -6,6 +6,24 @@ package object test {
     def withCompileScope: Dependency = underlying.copy(configuration = "compile")
   }
 
+  implicit class ResolutionOps(val underlying: Resolution) extends AnyVal {
+
+    // The content of these fields is typically not validated in the tests.
+    // It can be cleared with these method to it easier to compare `underlying`
+    // to an expected value.
+
+    def clearFinalDependenciesCache: Resolution =
+      underlying.copy(finalDependenciesCache = Map.empty)
+    def clearCaches: Resolution =
+      underlying.copy(
+        projectCache = Map.empty,
+        errorCache = Map.empty,
+        finalDependenciesCache = Map.empty
+      )
+    def clearFilter: Resolution =
+      underlying.copy(filter = None)
+  }
+
   object Profile {
     type Activation = core.Activation
     object Activation {