From 7a38a6582504d8a4244a3d704a9bf55a57705a08 Mon Sep 17 00:00:00 2001
From: Daniela Sfregola <daniela.sfregola@gmail.com>
Date: Sun, 15 Nov 2020 10:49:31 +0000
Subject: [PATCH 1/9] [unit 2] Migrated lesson 9 to scala 3.0.0-M1

---
 unit2/lesson9/build.sbt           | 2 +-
 unit2/lesson9/project/plugins.sbt | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)
 create mode 100644 unit2/lesson9/project/plugins.sbt

diff --git a/unit2/lesson9/build.sbt b/unit2/lesson9/build.sbt
index a6107a06..57c96075 100644
--- a/unit2/lesson9/build.sbt
+++ b/unit2/lesson9/build.sbt
@@ -2,4 +2,4 @@ name := "get-programming-with-scala-lesson9"
 
 version := "0.1"
 
-scalaVersion := "2.12.5"
\ No newline at end of file
+scalaVersion := "3.0.0-M1"
diff --git a/unit2/lesson9/project/plugins.sbt b/unit2/lesson9/project/plugins.sbt
new file mode 100644
index 00000000..04f707be
--- /dev/null
+++ b/unit2/lesson9/project/plugins.sbt
@@ -0,0 +1 @@
+addSbtPlugin("ch.epfl.lamp" % "sbt-dotty" % "0.4.5")

From d99fc2ac8a82c0b2fdf367fa9624358a534ef06f Mon Sep 17 00:00:00 2001
From: Daniela Sfregola <daniela.sfregola@gmail.com>
Date: Sun, 15 Nov 2020 11:42:12 +0000
Subject: [PATCH 2/9] [unit 2] Migrated lesson 10 to scala 3.0.0-M1

---
 unit2/lesson10/build.sbt           | 2 +-
 unit2/lesson10/project/plugins.sbt | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)
 create mode 100644 unit2/lesson10/project/plugins.sbt

diff --git a/unit2/lesson10/build.sbt b/unit2/lesson10/build.sbt
index 2a50c0d8..126ecee8 100644
--- a/unit2/lesson10/build.sbt
+++ b/unit2/lesson10/build.sbt
@@ -2,4 +2,4 @@ name := "get-programming-with-scala-lesson10"
 
 version := "0.1"
 
-scalaVersion := "2.12.5"
\ No newline at end of file
+scalaVersion := "3.0.0-M1"
diff --git a/unit2/lesson10/project/plugins.sbt b/unit2/lesson10/project/plugins.sbt
new file mode 100644
index 00000000..04f707be
--- /dev/null
+++ b/unit2/lesson10/project/plugins.sbt
@@ -0,0 +1 @@
+addSbtPlugin("ch.epfl.lamp" % "sbt-dotty" % "0.4.5")

From 01880c8c01ab910a5a3790e08fd3509f8346bc9e Mon Sep 17 00:00:00 2001
From: Daniela Sfregola <daniela.sfregola@gmail.com>
Date: Thu, 19 Nov 2020 09:51:18 +0000
Subject: [PATCH 3/9] [unit 2] Migrated lesson 11 to scala 3.0.0-M1

---
 unit2/lesson11/build.sbt           | 2 +-
 unit2/lesson11/project/plugins.sbt | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)
 create mode 100644 unit2/lesson11/project/plugins.sbt

diff --git a/unit2/lesson11/build.sbt b/unit2/lesson11/build.sbt
index d9c49987..ac05a9fb 100644
--- a/unit2/lesson11/build.sbt
+++ b/unit2/lesson11/build.sbt
@@ -2,4 +2,4 @@ name := "get-programming-with-scala-lesson11"
 
 version := "0.1"
 
-scalaVersion := "2.12.5"
\ No newline at end of file
+scalaVersion := "3.0.0-M1"
diff --git a/unit2/lesson11/project/plugins.sbt b/unit2/lesson11/project/plugins.sbt
new file mode 100644
index 00000000..04f707be
--- /dev/null
+++ b/unit2/lesson11/project/plugins.sbt
@@ -0,0 +1 @@
+addSbtPlugin("ch.epfl.lamp" % "sbt-dotty" % "0.4.5")

From 42609190a255978f75506426155bb318d83bdece Mon Sep 17 00:00:00 2001
From: Daniela Sfregola <daniela.sfregola@gmail.com>
Date: Thu, 19 Nov 2020 12:00:52 +0000
Subject: [PATCH 4/9] [unit 2] Migrated lesson 12 to scala 3.0.0-M1

---
 unit2/lesson12/build.sbt                                 | 2 +-
 unit2/lesson12/project/plugins.sbt                       | 1 +
 unit2/lesson12/src/main/scala/listings/Listing-12.2.sc   | 6 +-----
 unit2/lesson12/src/main/scala/listings/Listing-12.6.sc   | 6 ++++++
 unit2/lesson12/src/main/scala/listings/Listing-12.7.sc   | 9 +++++++++
 .../src/main/scala/quickchecks/QuickCheck-12.4.sc        | 9 +++++++++
 6 files changed, 27 insertions(+), 6 deletions(-)
 create mode 100644 unit2/lesson12/project/plugins.sbt
 create mode 100644 unit2/lesson12/src/main/scala/listings/Listing-12.6.sc
 create mode 100644 unit2/lesson12/src/main/scala/listings/Listing-12.7.sc
 create mode 100644 unit2/lesson12/src/main/scala/quickchecks/QuickCheck-12.4.sc

diff --git a/unit2/lesson12/build.sbt b/unit2/lesson12/build.sbt
index d3d90270..c725ba8f 100644
--- a/unit2/lesson12/build.sbt
+++ b/unit2/lesson12/build.sbt
@@ -2,4 +2,4 @@ name := "get-programming-with-scala-lesson12"
 
 version := "0.1"
 
-scalaVersion := "2.12.6"
\ No newline at end of file
+scalaVersion := "3.0.0-M1"
diff --git a/unit2/lesson12/project/plugins.sbt b/unit2/lesson12/project/plugins.sbt
new file mode 100644
index 00000000..04f707be
--- /dev/null
+++ b/unit2/lesson12/project/plugins.sbt
@@ -0,0 +1 @@
+addSbtPlugin("ch.epfl.lamp" % "sbt-dotty" % "0.4.5")
diff --git a/unit2/lesson12/src/main/scala/listings/Listing-12.2.sc b/unit2/lesson12/src/main/scala/listings/Listing-12.2.sc
index f55fb4f9..005e83da 100644
--- a/unit2/lesson12/src/main/scala/listings/Listing-12.2.sc
+++ b/unit2/lesson12/src/main/scala/listings/Listing-12.2.sc
@@ -1,5 +1 @@
-trait Nameable {
-
-  def name: String
-
-}
+trait Nameable(name: String)
diff --git a/unit2/lesson12/src/main/scala/listings/Listing-12.6.sc b/unit2/lesson12/src/main/scala/listings/Listing-12.6.sc
new file mode 100644
index 00000000..7c6576d4
--- /dev/null
+++ b/unit2/lesson12/src/main/scala/listings/Listing-12.6.sc
@@ -0,0 +1,6 @@
+enum Suit {
+  case Clubs, Diamonds, Hearts, Spades
+}
+
+
+Suit.Hearts
diff --git a/unit2/lesson12/src/main/scala/listings/Listing-12.7.sc b/unit2/lesson12/src/main/scala/listings/Listing-12.7.sc
new file mode 100644
index 00000000..8b365a01
--- /dev/null
+++ b/unit2/lesson12/src/main/scala/listings/Listing-12.7.sc
@@ -0,0 +1,9 @@
+enum Country(val code: String) {
+  case Italy extends Country("IT")
+  case UnitedKingdom extends Country("UK")
+  case UnitedStates extends Country("US")
+  case Japan extends Country("JP")
+}
+
+
+Country.Italy.code
diff --git a/unit2/lesson12/src/main/scala/quickchecks/QuickCheck-12.4.sc b/unit2/lesson12/src/main/scala/quickchecks/QuickCheck-12.4.sc
new file mode 100644
index 00000000..b0e1cdae
--- /dev/null
+++ b/unit2/lesson12/src/main/scala/quickchecks/QuickCheck-12.4.sc
@@ -0,0 +1,9 @@
+// In Quick Check 12.3, you have implemented a sealed trait Currency with three implementations:
+// re-implementing using enumeration syntax for Scala 3.
+
+
+// ANSWER
+
+enum Currency {
+  case USD, CAD, EUR
+}

From 37d98a0bbd2a91d2034a26fb8e4530826c27b264 Mon Sep 17 00:00:00 2001
From: Daniela Sfregola <daniela.sfregola@gmail.com>
Date: Thu, 19 Nov 2020 12:33:29 +0000
Subject: [PATCH 5/9] [unit 2] Migrated lesson 13 to scala 3.0.0-M1

---
 unit2/lesson13/build.sbt           | 2 +-
 unit2/lesson13/project/plugins.sbt | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)
 create mode 100644 unit2/lesson13/project/plugins.sbt

diff --git a/unit2/lesson13/build.sbt b/unit2/lesson13/build.sbt
index 5c29a38b..52811039 100644
--- a/unit2/lesson13/build.sbt
+++ b/unit2/lesson13/build.sbt
@@ -2,4 +2,4 @@ name := "get-programming-with-scala-lesson13"
 
 version := "0.1"
 
-scalaVersion := "2.12.6"
\ No newline at end of file
+scalaVersion := "3.0.0-M1"
diff --git a/unit2/lesson13/project/plugins.sbt b/unit2/lesson13/project/plugins.sbt
new file mode 100644
index 00000000..04f707be
--- /dev/null
+++ b/unit2/lesson13/project/plugins.sbt
@@ -0,0 +1 @@
+addSbtPlugin("ch.epfl.lamp" % "sbt-dotty" % "0.4.5")

From e0db3d05757c2388208633cc156ebc4b102ac6b9 Mon Sep 17 00:00:00 2001
From: Daniela Sfregola <daniela.sfregola@gmail.com>
Date: Mon, 28 Dec 2020 13:03:26 +0000
Subject: [PATCH 6/9] [unit 2] Upgraded to Scala 3.0.0-M3

---
 unit2/lesson10/build.sbt                | 2 +-
 unit2/lesson10/project/build.properties | 2 +-
 unit2/lesson10/project/plugins.sbt      | 2 +-
 unit2/lesson11/build.sbt                | 2 +-
 unit2/lesson11/project/build.properties | 2 +-
 unit2/lesson11/project/plugins.sbt      | 2 +-
 unit2/lesson12/build.sbt                | 2 +-
 unit2/lesson12/project/build.properties | 2 +-
 unit2/lesson12/project/plugins.sbt      | 2 +-
 unit2/lesson13/build.sbt                | 2 +-
 unit2/lesson13/project/build.properties | 2 +-
 unit2/lesson13/project/plugins.sbt      | 2 +-
 unit2/lesson9/build.sbt                 | 2 +-
 unit2/lesson9/project/build.properties  | 2 +-
 unit2/lesson9/project/plugins.sbt       | 2 +-
 15 files changed, 15 insertions(+), 15 deletions(-)

diff --git a/unit2/lesson10/build.sbt b/unit2/lesson10/build.sbt
index 126ecee8..43da1fcd 100644
--- a/unit2/lesson10/build.sbt
+++ b/unit2/lesson10/build.sbt
@@ -2,4 +2,4 @@ name := "get-programming-with-scala-lesson10"
 
 version := "0.1"
 
-scalaVersion := "3.0.0-M1"
+scalaVersion := "3.0.0-M3"
diff --git a/unit2/lesson10/project/build.properties b/unit2/lesson10/project/build.properties
index edb69425..fc08caee 100644
--- a/unit2/lesson10/project/build.properties
+++ b/unit2/lesson10/project/build.properties
@@ -1 +1 @@
-sbt.version = 1.4.2
+sbt.version = 1.4.4
diff --git a/unit2/lesson10/project/plugins.sbt b/unit2/lesson10/project/plugins.sbt
index 04f707be..a3cd5d37 100644
--- a/unit2/lesson10/project/plugins.sbt
+++ b/unit2/lesson10/project/plugins.sbt
@@ -1 +1 @@
-addSbtPlugin("ch.epfl.lamp" % "sbt-dotty" % "0.4.5")
+addSbtPlugin("ch.epfl.lamp" % "sbt-dotty" % "0.5.1")
diff --git a/unit2/lesson11/build.sbt b/unit2/lesson11/build.sbt
index ac05a9fb..4a2ff32e 100644
--- a/unit2/lesson11/build.sbt
+++ b/unit2/lesson11/build.sbt
@@ -2,4 +2,4 @@ name := "get-programming-with-scala-lesson11"
 
 version := "0.1"
 
-scalaVersion := "3.0.0-M1"
+scalaVersion := "3.0.0-M3"
diff --git a/unit2/lesson11/project/build.properties b/unit2/lesson11/project/build.properties
index edb69425..fc08caee 100644
--- a/unit2/lesson11/project/build.properties
+++ b/unit2/lesson11/project/build.properties
@@ -1 +1 @@
-sbt.version = 1.4.2
+sbt.version = 1.4.4
diff --git a/unit2/lesson11/project/plugins.sbt b/unit2/lesson11/project/plugins.sbt
index 04f707be..a3cd5d37 100644
--- a/unit2/lesson11/project/plugins.sbt
+++ b/unit2/lesson11/project/plugins.sbt
@@ -1 +1 @@
-addSbtPlugin("ch.epfl.lamp" % "sbt-dotty" % "0.4.5")
+addSbtPlugin("ch.epfl.lamp" % "sbt-dotty" % "0.5.1")
diff --git a/unit2/lesson12/build.sbt b/unit2/lesson12/build.sbt
index c725ba8f..754fb0bb 100644
--- a/unit2/lesson12/build.sbt
+++ b/unit2/lesson12/build.sbt
@@ -2,4 +2,4 @@ name := "get-programming-with-scala-lesson12"
 
 version := "0.1"
 
-scalaVersion := "3.0.0-M1"
+scalaVersion := "3.0.0-M3"
diff --git a/unit2/lesson12/project/build.properties b/unit2/lesson12/project/build.properties
index edb69425..fc08caee 100644
--- a/unit2/lesson12/project/build.properties
+++ b/unit2/lesson12/project/build.properties
@@ -1 +1 @@
-sbt.version = 1.4.2
+sbt.version = 1.4.4
diff --git a/unit2/lesson12/project/plugins.sbt b/unit2/lesson12/project/plugins.sbt
index 04f707be..a3cd5d37 100644
--- a/unit2/lesson12/project/plugins.sbt
+++ b/unit2/lesson12/project/plugins.sbt
@@ -1 +1 @@
-addSbtPlugin("ch.epfl.lamp" % "sbt-dotty" % "0.4.5")
+addSbtPlugin("ch.epfl.lamp" % "sbt-dotty" % "0.5.1")
diff --git a/unit2/lesson13/build.sbt b/unit2/lesson13/build.sbt
index 52811039..3688cfef 100644
--- a/unit2/lesson13/build.sbt
+++ b/unit2/lesson13/build.sbt
@@ -2,4 +2,4 @@ name := "get-programming-with-scala-lesson13"
 
 version := "0.1"
 
-scalaVersion := "3.0.0-M1"
+scalaVersion := "3.0.0-M3"
diff --git a/unit2/lesson13/project/build.properties b/unit2/lesson13/project/build.properties
index edb69425..fc08caee 100644
--- a/unit2/lesson13/project/build.properties
+++ b/unit2/lesson13/project/build.properties
@@ -1 +1 @@
-sbt.version = 1.4.2
+sbt.version = 1.4.4
diff --git a/unit2/lesson13/project/plugins.sbt b/unit2/lesson13/project/plugins.sbt
index 04f707be..a3cd5d37 100644
--- a/unit2/lesson13/project/plugins.sbt
+++ b/unit2/lesson13/project/plugins.sbt
@@ -1 +1 @@
-addSbtPlugin("ch.epfl.lamp" % "sbt-dotty" % "0.4.5")
+addSbtPlugin("ch.epfl.lamp" % "sbt-dotty" % "0.5.1")
diff --git a/unit2/lesson9/build.sbt b/unit2/lesson9/build.sbt
index 57c96075..e4c80134 100644
--- a/unit2/lesson9/build.sbt
+++ b/unit2/lesson9/build.sbt
@@ -2,4 +2,4 @@ name := "get-programming-with-scala-lesson9"
 
 version := "0.1"
 
-scalaVersion := "3.0.0-M1"
+scalaVersion := "3.0.0-M3"
diff --git a/unit2/lesson9/project/build.properties b/unit2/lesson9/project/build.properties
index edb69425..fc08caee 100644
--- a/unit2/lesson9/project/build.properties
+++ b/unit2/lesson9/project/build.properties
@@ -1 +1 @@
-sbt.version = 1.4.2
+sbt.version = 1.4.4
diff --git a/unit2/lesson9/project/plugins.sbt b/unit2/lesson9/project/plugins.sbt
index 04f707be..a3cd5d37 100644
--- a/unit2/lesson9/project/plugins.sbt
+++ b/unit2/lesson9/project/plugins.sbt
@@ -1 +1 @@
-addSbtPlugin("ch.epfl.lamp" % "sbt-dotty" % "0.4.5")
+addSbtPlugin("ch.epfl.lamp" % "sbt-dotty" % "0.5.1")

From 4a3ba95b506b11e0588a320258619db97c26c34d Mon Sep 17 00:00:00 2001
From: Daniela Sfregola <daniela.sfregola@gmail.com>
Date: Sat, 9 Jan 2021 12:58:32 +0000
Subject: [PATCH 7/9] [unit 2] Minor changes

---
 .../src/main/scala/listings/Listing-11.2.sc   |  2 +-
 .../src/main/scala/listings/Listing-12.2.sc   |  7 ++++++-
 .../src/main/scala/listings/Listing-12.4.sc   | 21 +++++++++++++++++++
 .../src/main/scala/listings/Listing-12.6.sc   |  2 ++
 .../src/main/scala/listings/Listing-9.4.md    |  1 -
 5 files changed, 30 insertions(+), 3 deletions(-)
 delete mode 100644 unit2/lesson9/src/main/scala/listings/Listing-9.4.md

diff --git a/unit2/lesson11/src/main/scala/listings/Listing-11.2.sc b/unit2/lesson11/src/main/scala/listings/Listing-11.2.sc
index e4c2429a..21ef4d90 100644
--- a/unit2/lesson11/src/main/scala/listings/Listing-11.2.sc
+++ b/unit2/lesson11/src/main/scala/listings/Listing-11.2.sc
@@ -2,7 +2,7 @@
   * public class MySingleton {
   * private static MySingleton instance = null;
   **
-  *protected MySingleton() {}
+  *private MySingleton() {}
   **
   *public static MySingleton getInstance() {
   * if(instance == null) {
diff --git a/unit2/lesson12/src/main/scala/listings/Listing-12.2.sc b/unit2/lesson12/src/main/scala/listings/Listing-12.2.sc
index 005e83da..d54bf393 100644
--- a/unit2/lesson12/src/main/scala/listings/Listing-12.2.sc
+++ b/unit2/lesson12/src/main/scala/listings/Listing-12.2.sc
@@ -1 +1,6 @@
-trait Nameable(name: String)
+trait Nameable {
+  def name: String
+}
+
+// which you can rewrite in Scala 3 as:
+// trait Nameable(name: String)
diff --git a/unit2/lesson12/src/main/scala/listings/Listing-12.4.sc b/unit2/lesson12/src/main/scala/listings/Listing-12.4.sc
index 7067d750..d57bca99 100644
--- a/unit2/lesson12/src/main/scala/listings/Listing-12.4.sc
+++ b/unit2/lesson12/src/main/scala/listings/Listing-12.4.sc
@@ -19,3 +19,24 @@ class Dog(val name: String) extends Animal with Nameable {
 
   def move(x: Int, y: Int) = "let's go to ($x, $y)!"
 }
+
+class Cat extends Animal {
+
+  override val sleep = "sleepy cat!"
+
+  def eat(food: String) = s"the cat is eating $food"
+
+  def move(x: Int, y: Int) = s"the cat is moving to ($x,$y)"
+}
+
+
+val tiggerTheDog = new Dog("Tigger")
+val cat = new Cat
+
+def feedTreat(animal: Animal) = animal.eat("treat")
+feedTreat(tiggerTheDog)
+feedTreat(cat)
+
+def welcome(nameable: Nameable) = println(s"Hi, ${nameable.name}!")
+welcome(tiggerTheDog)
+welcome(cat) // Doesn't compile - Cat doesn't extend Nameable
diff --git a/unit2/lesson12/src/main/scala/listings/Listing-12.6.sc b/unit2/lesson12/src/main/scala/listings/Listing-12.6.sc
index 7c6576d4..36498370 100644
--- a/unit2/lesson12/src/main/scala/listings/Listing-12.6.sc
+++ b/unit2/lesson12/src/main/scala/listings/Listing-12.6.sc
@@ -4,3 +4,5 @@ enum Suit {
 
 
 Suit.Hearts
+Suit.values
+Suit.fromOrdinal(0)
diff --git a/unit2/lesson9/src/main/scala/listings/Listing-9.4.md b/unit2/lesson9/src/main/scala/listings/Listing-9.4.md
deleted file mode 100644
index 03f89d02..00000000
--- a/unit2/lesson9/src/main/scala/listings/Listing-9.4.md
+++ /dev/null
@@ -1 +0,0 @@
-See files MyFile1.scala and MyFile2.scala in the directory src/main/scala/my/example/io

From 83a206aacc91cee8838a0f310ed2fc16e8e9967c Mon Sep 17 00:00:00 2001
From: Daniela Sfregola <daniela.sfregola@gmail.com>
Date: Tue, 26 Jan 2021 14:31:11 +0000
Subject: [PATCH 8/9] [unit 2] More Minor changes

---
 unit2/lesson11/src/main/scala/quickchecks/QuickCheck-11.1.sc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/unit2/lesson11/src/main/scala/quickchecks/QuickCheck-11.1.sc b/unit2/lesson11/src/main/scala/quickchecks/QuickCheck-11.1.sc
index 9f6a3343..e18fce78 100644
--- a/unit2/lesson11/src/main/scala/quickchecks/QuickCheck-11.1.sc
+++ b/unit2/lesson11/src/main/scala/quickchecks/QuickCheck-11.1.sc
@@ -13,7 +13,7 @@ new MySnippet
 // scala> new MySnippet
 // <console>:11: error: not found: type MySnippet
 //
-// The first statement successfully defines an object called “MySnippet”.
+// The first expression successfully defines an object called “MySnippet”.
 // The second one is incorrect: you cannot request the creation of an object.
 // When using the keyword new the compiler looks for a class or type called “MySnippet”:
 // an object is neither, so the compiler rejects it with a missing type error.

From bd8ab1e60024c13c579ebe2e2a00f64262e9b8d4 Mon Sep 17 00:00:00 2001
From: Daniela Sfregola <daniela.sfregola@gmail.com>
Date: Sun, 21 Feb 2021 10:48:03 +0000
Subject: [PATCH 9/9] [unit 2] Upgrade to Scala 3-RC1

---
 unit2/lesson10/build.sbt                | 2 +-
 unit2/lesson10/project/build.properties | 2 +-
 unit2/lesson10/project/plugins.sbt      | 2 +-
 unit2/lesson11/build.sbt                | 2 +-
 unit2/lesson11/project/build.properties | 2 +-
 unit2/lesson11/project/plugins.sbt      | 2 +-
 unit2/lesson12/build.sbt                | 2 +-
 unit2/lesson12/project/build.properties | 2 +-
 unit2/lesson12/project/plugins.sbt      | 2 +-
 unit2/lesson13/build.sbt                | 2 +-
 unit2/lesson13/project/build.properties | 2 +-
 unit2/lesson13/project/plugins.sbt      | 2 +-
 unit2/lesson9/build.sbt                 | 2 +-
 unit2/lesson9/project/build.properties  | 2 +-
 unit2/lesson9/project/plugins.sbt       | 2 +-
 15 files changed, 15 insertions(+), 15 deletions(-)

diff --git a/unit2/lesson10/build.sbt b/unit2/lesson10/build.sbt
index 43da1fcd..bae25533 100644
--- a/unit2/lesson10/build.sbt
+++ b/unit2/lesson10/build.sbt
@@ -2,4 +2,4 @@ name := "get-programming-with-scala-lesson10"
 
 version := "0.1"
 
-scalaVersion := "3.0.0-M3"
+scalaVersion := "3.0.0-RC1"
diff --git a/unit2/lesson10/project/build.properties b/unit2/lesson10/project/build.properties
index fc08caee..d18a12ed 100644
--- a/unit2/lesson10/project/build.properties
+++ b/unit2/lesson10/project/build.properties
@@ -1 +1 @@
-sbt.version = 1.4.4
+sbt.version = 1.4.7
diff --git a/unit2/lesson10/project/plugins.sbt b/unit2/lesson10/project/plugins.sbt
index a3cd5d37..b6f51067 100644
--- a/unit2/lesson10/project/plugins.sbt
+++ b/unit2/lesson10/project/plugins.sbt
@@ -1 +1 @@
-addSbtPlugin("ch.epfl.lamp" % "sbt-dotty" % "0.5.1")
+addSbtPlugin("ch.epfl.lamp" % "sbt-dotty" % "0.5.3")
diff --git a/unit2/lesson11/build.sbt b/unit2/lesson11/build.sbt
index 4a2ff32e..79280f24 100644
--- a/unit2/lesson11/build.sbt
+++ b/unit2/lesson11/build.sbt
@@ -2,4 +2,4 @@ name := "get-programming-with-scala-lesson11"
 
 version := "0.1"
 
-scalaVersion := "3.0.0-M3"
+scalaVersion := "3.0.0-RC1"
diff --git a/unit2/lesson11/project/build.properties b/unit2/lesson11/project/build.properties
index fc08caee..d18a12ed 100644
--- a/unit2/lesson11/project/build.properties
+++ b/unit2/lesson11/project/build.properties
@@ -1 +1 @@
-sbt.version = 1.4.4
+sbt.version = 1.4.7
diff --git a/unit2/lesson11/project/plugins.sbt b/unit2/lesson11/project/plugins.sbt
index a3cd5d37..b6f51067 100644
--- a/unit2/lesson11/project/plugins.sbt
+++ b/unit2/lesson11/project/plugins.sbt
@@ -1 +1 @@
-addSbtPlugin("ch.epfl.lamp" % "sbt-dotty" % "0.5.1")
+addSbtPlugin("ch.epfl.lamp" % "sbt-dotty" % "0.5.3")
diff --git a/unit2/lesson12/build.sbt b/unit2/lesson12/build.sbt
index 754fb0bb..886247bd 100644
--- a/unit2/lesson12/build.sbt
+++ b/unit2/lesson12/build.sbt
@@ -2,4 +2,4 @@ name := "get-programming-with-scala-lesson12"
 
 version := "0.1"
 
-scalaVersion := "3.0.0-M3"
+scalaVersion := "3.0.0-RC1"
diff --git a/unit2/lesson12/project/build.properties b/unit2/lesson12/project/build.properties
index fc08caee..d18a12ed 100644
--- a/unit2/lesson12/project/build.properties
+++ b/unit2/lesson12/project/build.properties
@@ -1 +1 @@
-sbt.version = 1.4.4
+sbt.version = 1.4.7
diff --git a/unit2/lesson12/project/plugins.sbt b/unit2/lesson12/project/plugins.sbt
index a3cd5d37..b6f51067 100644
--- a/unit2/lesson12/project/plugins.sbt
+++ b/unit2/lesson12/project/plugins.sbt
@@ -1 +1 @@
-addSbtPlugin("ch.epfl.lamp" % "sbt-dotty" % "0.5.1")
+addSbtPlugin("ch.epfl.lamp" % "sbt-dotty" % "0.5.3")
diff --git a/unit2/lesson13/build.sbt b/unit2/lesson13/build.sbt
index 3688cfef..079385af 100644
--- a/unit2/lesson13/build.sbt
+++ b/unit2/lesson13/build.sbt
@@ -2,4 +2,4 @@ name := "get-programming-with-scala-lesson13"
 
 version := "0.1"
 
-scalaVersion := "3.0.0-M3"
+scalaVersion := "3.0.0-RC1"
diff --git a/unit2/lesson13/project/build.properties b/unit2/lesson13/project/build.properties
index fc08caee..d18a12ed 100644
--- a/unit2/lesson13/project/build.properties
+++ b/unit2/lesson13/project/build.properties
@@ -1 +1 @@
-sbt.version = 1.4.4
+sbt.version = 1.4.7
diff --git a/unit2/lesson13/project/plugins.sbt b/unit2/lesson13/project/plugins.sbt
index a3cd5d37..b6f51067 100644
--- a/unit2/lesson13/project/plugins.sbt
+++ b/unit2/lesson13/project/plugins.sbt
@@ -1 +1 @@
-addSbtPlugin("ch.epfl.lamp" % "sbt-dotty" % "0.5.1")
+addSbtPlugin("ch.epfl.lamp" % "sbt-dotty" % "0.5.3")
diff --git a/unit2/lesson9/build.sbt b/unit2/lesson9/build.sbt
index e4c80134..b88fad5d 100644
--- a/unit2/lesson9/build.sbt
+++ b/unit2/lesson9/build.sbt
@@ -2,4 +2,4 @@ name := "get-programming-with-scala-lesson9"
 
 version := "0.1"
 
-scalaVersion := "3.0.0-M3"
+scalaVersion := "3.0.0-RC1"
diff --git a/unit2/lesson9/project/build.properties b/unit2/lesson9/project/build.properties
index fc08caee..d18a12ed 100644
--- a/unit2/lesson9/project/build.properties
+++ b/unit2/lesson9/project/build.properties
@@ -1 +1 @@
-sbt.version = 1.4.4
+sbt.version = 1.4.7
diff --git a/unit2/lesson9/project/plugins.sbt b/unit2/lesson9/project/plugins.sbt
index a3cd5d37..b6f51067 100644
--- a/unit2/lesson9/project/plugins.sbt
+++ b/unit2/lesson9/project/plugins.sbt
@@ -1 +1 @@
-addSbtPlugin("ch.epfl.lamp" % "sbt-dotty" % "0.5.1")
+addSbtPlugin("ch.epfl.lamp" % "sbt-dotty" % "0.5.3")