diff --git a/.drone.yml b/.drone.yml
index aa248459bcb1..8ef737a3da79 100644
--- a/.drone.yml
+++ b/.drone.yml
@@ -11,9 +11,7 @@ pipeline:
     image: lampepfl/dotty:24-04-2017
     pull: true
     commands:
-      - ln -s /var/cache/drone/scala-scala scala-scala
       - ln -s /var/cache/drone/ivy2 "$HOME/.ivy2"
-      - ./project/scripts/updateScalaLibrary
       - sbt -J-Xmx4096m -J-XX:ReservedCodeCacheSize=512m -J-XX:MaxMetaspaceSize=1024m -Ddotty.drone.mem=4096m "${CI_TEST}"
     when:
       branch:
diff --git a/.gitignore b/.gitignore
index 7508b4932d95..3648eddf0044 100644
--- a/.gitignore
+++ b/.gitignore
@@ -37,9 +37,6 @@ tests/partest-generated/
 tests/locks/
 /test-classes/
 
-# Used in tests
-scala-scala
-
 # Ignore output files but keep the directory
 out/
 build/
diff --git a/.gitmodules b/.gitmodules
index 37937bd8e575..f5ea01ebbaab 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -2,3 +2,11 @@
 	path = scala-backend
 	url = https://github.com/lampepfl/scala.git
 	branch = sharing-backend
+[submodule "scala2-library"]
+	path = scala2-library
+	url = https://github.com/lampepfl/scala.git
+	branch = dotty-library
+[submodule "collection-strawman"]
+	path = collection-strawman
+	url = https://github.com/scala/collection-strawman.git
+	branch = master
diff --git a/collection-strawman b/collection-strawman
new file mode 160000
index 000000000000..3dd7d3b36ecb
--- /dev/null
+++ b/collection-strawman
@@ -0,0 +1 @@
+Subproject commit 3dd7d3b36ecb30d35d9e2c4ccbd6b7a616d2666e
diff --git a/compiler/test/dotc/tests.scala b/compiler/test/dotc/tests.scala
index 3c07df88a952..4af6277f05f4 100644
--- a/compiler/test/dotc/tests.scala
+++ b/compiler/test/dotc/tests.scala
@@ -215,18 +215,18 @@ class tests extends CompilerTest {
 
   @Test def compileMixed = compileLine(
       """../tests/pos/B.scala
-        |../scala-scala/src/library/scala/collection/immutable/Seq.scala
-        |../scala-scala/src/library/scala/collection/parallel/ParSeq.scala
-        |../scala-scala/src/library/scala/package.scala
-        |../scala-scala/src/library/scala/collection/GenSeqLike.scala
-        |../scala-scala/src/library/scala/collection/SeqLike.scala
-        |../scala-scala/src/library/scala/collection/generic/GenSeqFactory.scala""".stripMargin)
-  @Test def compileIndexedSeq = compileLine("../scala-scala/src/library/scala/collection/immutable/IndexedSeq.scala")
-  @Test def compileParSetLike = compileLine("../scala-scala/src/library/scala/collection/parallel/mutable/ParSetLike.scala")
+        |../scala2-library/src/library/scala/collection/immutable/Seq.scala
+        |../scala2-library/src/library/scala/collection/parallel/ParSeq.scala
+        |../scala2-library/src/library/scala/package.scala
+        |../scala2-library/src/library/scala/collection/GenSeqLike.scala
+        |../scala2-library/src/library/scala/collection/SeqLike.scala
+        |../scala2-library/src/library/scala/collection/generic/GenSeqFactory.scala""".stripMargin)
+  @Test def compileIndexedSeq = compileLine("../scala2-library/src/library/scala/collection/immutable/IndexedSeq.scala")
+  @Test def compileParSetLike = compileLine("../scala2-library/src/library/scala/collection/parallel/mutable/ParSetLike.scala")
   @Test def compileParSetSubset = compileLine(
-      """../scala-scala/src/library/scala/collection/parallel/mutable/ParSetLike.scala
-        |../scala-scala/src/library/scala/collection/parallel/mutable/ParSet.scala
-        |../scala-scala/src/library/scala/collection/mutable/SetLike.scala""".stripMargin)(scala2mode ++ defaultOptions)
+      """../scala2-library/src/library/scala/collection/parallel/mutable/ParSetLike.scala
+        |../scala2-library/src/library/scala/collection/parallel/mutable/ParSet.scala
+        |../scala2-library/src/library/scala/collection/mutable/SetLike.scala""".stripMargin)(scala2mode ++ defaultOptions)
 
   @Test def dottyBooted = {
     dottyBootedLib
diff --git a/compiler/test/dotty/tools/StdLibSources.scala b/compiler/test/dotty/tools/StdLibSources.scala
index 0c11210586a3..2b8a9574b758 100644
--- a/compiler/test/dotty/tools/StdLibSources.scala
+++ b/compiler/test/dotty/tools/StdLibSources.scala
@@ -10,7 +10,7 @@ object StdLibSources {
   /* For debug only */
   private val useExplicitWhiteList = false
 
-  private final val stdLibPath = "../scala-scala/src/library/"
+  private final val stdLibPath = "../scala2-library/src/library/"
 
   def blacklistFile: String = "../compiler/test/dotc/scala-collections.blacklist"
   private def whitelistFile: String = "../compiler/test/dotc/scala-collections.whitelist"
diff --git a/compiler/test/dotty/tools/dotc/CompilationTests.scala b/compiler/test/dotty/tools/dotc/CompilationTests.scala
index df7a1141cec9..8a2cc2130cb8 100644
--- a/compiler/test/dotty/tools/dotc/CompilationTests.scala
+++ b/compiler/test/dotty/tools/dotc/CompilationTests.scala
@@ -29,6 +29,7 @@ class CompilationTests extends ParallelTesting {
 
   @Test def compilePos: Unit = {
     compileList("compileStdLib", StdLibSources.whitelisted, scala2Mode.and("-migration", "-Yno-inline")) +
+    compileDir("../collection-strawman/src/main", defaultOptions) +
     compileDir("../compiler/src/dotty/tools/dotc/ast", defaultOptions) +
     compileDir("../compiler/src/dotty/tools/dotc/config", defaultOptions) +
     compileDir("../compiler/src/dotty/tools/dotc/core", allowDeepSubtypes) +
@@ -49,24 +50,24 @@ class CompilationTests extends ParallelTesting {
       "compileMixed",
       List(
         "../tests/pos/B.scala",
-        "../scala-scala/src/library/scala/collection/immutable/Seq.scala",
-        "../scala-scala/src/library/scala/collection/parallel/ParSeq.scala",
-        "../scala-scala/src/library/scala/package.scala",
-        "../scala-scala/src/library/scala/collection/GenSeqLike.scala",
-        "../scala-scala/src/library/scala/collection/SeqLike.scala",
-        "../scala-scala/src/library/scala/collection/generic/GenSeqFactory.scala"
+        "../scala2-library/src/library/scala/collection/immutable/Seq.scala",
+        "../scala2-library/src/library/scala/collection/parallel/ParSeq.scala",
+        "../scala2-library/src/library/scala/package.scala",
+        "../scala2-library/src/library/scala/collection/GenSeqLike.scala",
+        "../scala2-library/src/library/scala/collection/SeqLike.scala",
+        "../scala2-library/src/library/scala/collection/generic/GenSeqFactory.scala"
       ),
       defaultOptions
     ) +
     compileFilesInDir("../tests/pos-special/spec-t5545", defaultOptions) +
-    compileFile("../scala-scala/src/library/scala/collection/immutable/IndexedSeq.scala", defaultOptions) +
-    compileFile("../scala-scala/src/library/scala/collection/parallel/mutable/ParSetLike.scala", defaultOptions) +
+    compileFile("../scala2-library/src/library/scala/collection/immutable/IndexedSeq.scala", defaultOptions) +
+    compileFile("../scala2-library/src/library/scala/collection/parallel/mutable/ParSetLike.scala", defaultOptions) +
     compileList(
       "parSetSubset",
       List(
-       "../scala-scala/src/library/scala/collection/parallel/mutable/ParSetLike.scala",
-       "../scala-scala/src/library/scala/collection/parallel/mutable/ParSet.scala",
-       "../scala-scala/src/library/scala/collection/mutable/SetLike.scala"
+       "../scala2-library/src/library/scala/collection/parallel/mutable/ParSetLike.scala",
+       "../scala2-library/src/library/scala/collection/parallel/mutable/ParSet.scala",
+       "../scala2-library/src/library/scala/collection/mutable/SetLike.scala"
       ),
       scala2Mode
     ) +
diff --git a/compiler/test/dotty/tools/dotc/parsing/ScannerTest.scala b/compiler/test/dotty/tools/dotc/parsing/ScannerTest.scala
index b024a63dba2f..48ac280d0578 100644
--- a/compiler/test/dotty/tools/dotc/parsing/ScannerTest.scala
+++ b/compiler/test/dotty/tools/dotc/parsing/ScannerTest.scala
@@ -60,6 +60,6 @@ class ScannerTest extends DottyTest {
 
   @Test
   def scanScala() = {
-    scanDir("../scala-scala/src")
+    scanDir("../scala2-library/src")
   }
 }
diff --git a/compiler/test/dotty/tools/dotc/parsing/desugarPackage.scala b/compiler/test/dotty/tools/dotc/parsing/desugarPackage.scala
index 84bf7a2d174e..0ca15b9172c9 100644
--- a/compiler/test/dotty/tools/dotc/parsing/desugarPackage.scala
+++ b/compiler/test/dotty/tools/dotc/parsing/desugarPackage.scala
@@ -12,7 +12,7 @@ object desugarPackage extends DeSugarTest {
     val start = System.nanoTime()
     val startNodes = Trees.ntrees
     parseDir("./src")
-    parseDir("./scala-scala/src")
+    parseDir("./scala2-library/src")
     val ms1 = (System.nanoTime() - start)/1000000
     val nodes = Trees.ntrees
     val buf = parsedTrees map desugarTree
diff --git a/compiler/test/dotty/tools/dotc/parsing/parsePackage.scala b/compiler/test/dotty/tools/dotc/parsing/parsePackage.scala
index df5368ffe337..9e0e2829233e 100644
--- a/compiler/test/dotty/tools/dotc/parsing/parsePackage.scala
+++ b/compiler/test/dotty/tools/dotc/parsing/parsePackage.scala
@@ -68,7 +68,7 @@ object parsePackage extends ParserTest {
     nodes = 0
     val start = System.nanoTime()
     parseDir("./src")
-    parseDir("./scala-scala/src")
+    parseDir("./scala2-library/src")
     val ms1 = (System.nanoTime() - start)/1000000
     val buf = parsedTrees map transformer.transform
     val ms2 = (System.nanoTime() - start)/1000000
diff --git a/doc-tool/test/UsecaseTest.scala b/doc-tool/test/UsecaseTest.scala
index 4eb072b98ff8..f0f38d09f79d 100644
--- a/doc-tool/test/UsecaseTest.scala
+++ b/doc-tool/test/UsecaseTest.scala
@@ -223,12 +223,12 @@ class UsecaseTest extends DottyDocTest {
   }
 
   @Test def checkIterator =
-    checkFiles("../scala-scala/src/library/scala/collection/Iterator.scala" :: Nil) { _ =>
+    checkFiles("../scala2-library/src/library/scala/collection/Iterator.scala" :: Nil) { _ =>
       // success if typer throws no errors! :)
     }
 
   @Test def checkIterableLike =
-    checkFiles("../scala-scala/src/library/scala/collection/IterableLike.scala" :: Nil) { _ =>
+    checkFiles("../scala2-library/src/library/scala/collection/IterableLike.scala" :: Nil) { _ =>
       // success if typer throws no errors! :)
     }
 }
diff --git a/docs/docs/contributing/workflow.md b/docs/docs/contributing/workflow.md
index a8001366ae41..86320426f972 100644
--- a/docs/docs/contributing/workflow.md
+++ b/docs/docs/contributing/workflow.md
@@ -11,8 +11,6 @@ This document details common workflow patterns when working with Dotty.
 # Start by cloning the repository:
 git clone --recursive https://github.com/lampepfl/dotty.git
 cd dotty
-# Clone dotty-compatible stdlib. Needed for running the test suite.
-git clone -b dotty-library https://github.com/DarkDimius/scala.git scala-scala
 ```
 
 ## Compiling files with dotc ##
diff --git a/project/Build.scala b/project/Build.scala
index 5da8d8549581..f5baa18b8c17 100644
--- a/project/Build.scala
+++ b/project/Build.scala
@@ -24,8 +24,6 @@ object ExposedValues extends AutoPlugin {
 
 object Build {
 
-  projectChecks()
-
   val scalacVersion = "2.11.11" // Do not rename, this is grepped in bin/common.
 
   val dottyOrganization = "ch.epfl.lamp"
@@ -152,7 +150,7 @@ object Build {
     scalacOptions ++= Seq("-bootclasspath", sys.props("sun.boot.class.path")),
 
     // sbt gets very unhappy if two projects use the same target
-    target := baseDirectory.value / ".." / "out" / name.value,
+    target := baseDirectory.value / ".." / "out" / "bootstrap" / name.value,
 
     // The non-bootstrapped dotty-library is not necessary when bootstrapping dotty
     autoScalaLibrary := false,
@@ -234,7 +232,7 @@ object Build {
     settings(commonNonBootstrappedSettings).
     settings(
       triggeredMessage in ThisBuild := Watched.clearWhenTriggered,
-
+      submoduleChecks,
       addCommandAlias("run", "dotty-compiler/run") ++
       addCommandAlias("legacyTests", "dotty-compiler/testOnly dotc.tests")
     )
@@ -995,14 +993,15 @@ object DottyInjectedPlugin extends AutoPlugin {
     ))
   }
 
-  private def projectChecks(): Unit = {
-    val scalaScala = new File("scala-scala")
-    if (!scalaScala.exists()) {
-      println(
-        s"""[WARNING] Missing `dotty/scala-scala` library
-           |You can clone the library with:
-           |  > git clone -b dotty-library https://github.com/DarkDimius/scala.git ${scalaScala.getAbsolutePath}
+  lazy val submoduleChecks = onLoad in Global := (onLoad in Global).value andThen { state =>
+    val submodules = List(new File("scala-backend"), new File("scala2-library"), new File("collection-strawman"))
+    if (!submodules.forall(f => f.exists && f.listFiles().nonEmpty)) {
+      sLog.value.log(Level.Error,
+        s"""Missing some of the submodules
+           |You can initialize the modules with:
+           |  > git submodule update --init
         """.stripMargin)
     }
+    state
   }
 }
diff --git a/project/scripts/updateScalaLibrary b/project/scripts/updateScalaLibrary
deleted file mode 100755
index 3aad6aa867ef..000000000000
--- a/project/scripts/updateScalaLibrary
+++ /dev/null
@@ -1,23 +0,0 @@
-#!/usr/bin/env bash
-
-update() {
-  [[ -d $baseDir ]] || mkdir -p $baseDir
-  cd $baseDir
-
-  if [ ! -d $baseDir/$3 ]; then git clone "https://github.com/$1/$2.git" $3; fi
-
-  cd $3
-
-  git fetch --tags "https://github.com/$1/$2.git"
-  (git fetch "https://github.com/$1/$2.git" $4 && git checkout -fq FETCH_HEAD) #|| git checkout -fq $4 # || fallback is for local testing on tag
-  git reset --hard
-  echo updated $1/$2:$4 under $3. Last commits:
-  git --no-pager log --pretty=format:"%h - %an, %aD : %s" -n 10 # show last commits
-  cd -
-}
-
-export LC_ALL=en_US.UTF-8
-
-baseDir=`pwd`
-
-update DarkDimius scala scala-scala dotty-library
diff --git a/scala2-library b/scala2-library
new file mode 160000
index 000000000000..c14809b706da
--- /dev/null
+++ b/scala2-library
@@ -0,0 +1 @@
+Subproject commit c14809b706da013349581c713a7fde04ed47d2d3