diff --git a/.gitignore b/.gitignore
index 96ca049..d4601a2 100644
--- a/.gitignore
+++ b/.gitignore
@@ -13,6 +13,7 @@ out
 .classpath
 .project
 .settings
+.vscode/settings.json
 
 # Compiled class file
 *.class
diff --git a/.vscode/settings.json b/.vscode/settings.json
deleted file mode 100644
index 52a1bb5..0000000
--- a/.vscode/settings.json
+++ /dev/null
@@ -1,4 +0,0 @@
-{
-  "java.configuration.updateBuildConfiguration": "automatic",
-  "plantuml.server": "https://www.plantuml.com/plantuml"
-}
diff --git a/build.gradle b/build.gradle
index 70fef4e..195ac77 100644
--- a/build.gradle
+++ b/build.gradle
@@ -18,17 +18,13 @@ repositories {
 }
 
 dependencies {
-    // This dependency is exported to consumers, that is to say found on their compile classpath.
-    api 'org.apache.commons:commons-math3:3.6.1'
-
-    // This dependency is used internally, and not exposed to consumers on their own compile classpath.
-    implementation 'com.google.guava:guava:28.0-jre'
-
-    // Use JUnit Jupiter API for testing.
-    testImplementation 'org.junit.jupiter:junit-jupiter-api:5.4.2'
-
-    // Use JUnit Jupiter Engine for testing.
-    testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.4.2'
+    api(platform("org.junit:junit-bom:5.7.0"))
+    api("org.junit.jupiter:junit-jupiter-api") {
+        because 'building extensions in "main" using JUnit Jupiter API'
+    }
+    testRuntimeOnly("org.junit.jupiter:junit-jupiter-engine") {
+        because 'at least one engine is needed at test runtime'
+    }
 }
 
 test {
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
index 5028f28..28ff446 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -1,5 +1,5 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-5.6.4-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.8.1-bin.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
diff --git a/src/main/java/com/tetras/Carre.java b/src/main/java/com/tetras/Carre.java
new file mode 100644
index 0000000..58f8c52
--- /dev/null
+++ b/src/main/java/com/tetras/Carre.java
@@ -0,0 +1,7 @@
+package com.tetras;
+
+public class Carre {
+    public void dessiner() {
+        System.out.println("Carré dessiné");
+    }
+}
\ No newline at end of file
diff --git a/src/main/java/com/tetras/Dessin.java b/src/main/java/com/tetras/Dessin.java
new file mode 100644
index 0000000..fa63415
--- /dev/null
+++ b/src/main/java/com/tetras/Dessin.java
@@ -0,0 +1,13 @@
+package com.tetras;
+
+public class Dessin {
+    public void dessiner() {
+        System.out.println("Dessin dessiné");
+    }
+
+    public void ajouter(Carre carre) {
+    }
+
+    public void ajouter(Rond rond) {
+    }
+}
\ No newline at end of file
diff --git a/src/main/java/com/tetras/Rond.java b/src/main/java/com/tetras/Rond.java
new file mode 100644
index 0000000..c9cf841
--- /dev/null
+++ b/src/main/java/com/tetras/Rond.java
@@ -0,0 +1,7 @@
+package com.tetras;
+
+public class Rond {
+    public void dessiner() {
+        System.out.println("Rond dessiné");
+    }
+}
\ No newline at end of file
diff --git a/src/main/resources/TODO.txt b/src/main/resources/TODO.txt
new file mode 100644
index 0000000..390c386
--- /dev/null
+++ b/src/main/resources/TODO.txt
@@ -0,0 +1 @@
+Remove me
\ No newline at end of file
diff --git a/src/test/java/com/tetras/DessinTest.java b/src/test/java/com/tetras/DessinTest.java
new file mode 100644
index 0000000..96342bf
--- /dev/null
+++ b/src/test/java/com/tetras/DessinTest.java
@@ -0,0 +1,45 @@
+package com.tetras;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.io.ByteArrayOutputStream;
+import java.io.PrintStream;
+import java.io.PrintWriter;
+import java.io.StringWriter;
+
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+public class DessinTest {
+
+    private final ByteArrayOutputStream outContent = new ByteArrayOutputStream();
+    private final PrintStream originalOut = System.out;
+
+    @BeforeEach
+    public void setUpStreams() {
+        System.setOut(new PrintStream(outContent));
+    }
+
+    @AfterEach
+    public void restoreStreams() {
+        System.setOut(originalOut);
+    }
+
+    @Test
+    public void testDessiner() {
+        //
+        Dessin dessin = new Dessin();
+        dessin.ajouter(new Rond());
+        dessin.ajouter(new Carre());
+        dessin.dessiner();
+        //
+        StringWriter out = new StringWriter();
+        PrintWriter writer = new PrintWriter(out);
+        writer.println("Rond dessiné");
+        writer.println("Carré dessiné");
+        writer.println("Dessin dessiné");
+        //
+        assertEquals(out.toString(), outContent.toString());
+    }
+}
\ No newline at end of file
diff --git a/src/uml/composition.puml b/src/uml/composition.puml
new file mode 100644
index 0000000..8ded402
--- /dev/null
+++ b/src/uml/composition.puml
@@ -0,0 +1,13 @@
+@startuml Composite
+class Carre {
+    + dessiner() :void
+}
+class Rond {
+    + dessiner() :void
+}
+class Dessin {
+    + dessiner():void
+    + ajouter(Rond): void
+    + ajouter(Carre): void
+}
+@enduml
\ No newline at end of file