diff --git a/.gitignore b/.gitignore
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,4 @@
 build/
+
+/vendor/
+composer.lock
diff --git a/Makefile b/Makefile
--- a/Makefile
+++ b/Makefile
@@ -3,12 +3,19 @@
 ### We use PHPUnit to test several parts of our infrastructure.
 ###
 
+PHPUNIT=vendor/bin/phpunit
+
 ENV_FOR_TEST_FULL= \
 	DOCKER_ACCESS=1 \
 	DOCKER_HOST=equatower.nasqueron.org \
 
-test:
-	phpunit --log-junit build/phpunit.xml -v .
+all: test
+
+vendor:
+	composer install
+
+test: vendor
+	${PHPUNIT} --log-junit build/phpunit.xml -v
 
-test-full:
-	sh -c "${ENV_FOR_TEST_FULL} phpunit --log-junit build/phpunit.xml -v ."
+test-full: vendor
+	sh -c "${ENV_FOR_TEST_FULL} ${PHPUNIT} --log-junit build/phpunit.xml -v"
diff --git a/composer.json b/composer.json
new file mode 100644
--- /dev/null
+++ b/composer.json
@@ -0,0 +1,15 @@
+{
+    "name": "nasqueron/tests-prod-environment-behaves-correctly",
+    "description": "Tests to validate production environment",
+    "type": "project",
+    "require": {
+        "phpunit/phpunit": "^7.3"
+    },
+    "license": "BSD-2-Clause",
+    "authors": [
+        {
+            "name": "Sébastien Santoro",
+            "email": "dereckson@espace-win.org"
+        }
+    ]
+}
diff --git a/phpunit.xml b/phpunit.xml
new file mode 100644
--- /dev/null
+++ b/phpunit.xml
@@ -0,0 +1,11 @@
+<phpunit
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/7.3/phpunit.xsd"
+>
+    <testsuites>
+        <testsuite name="Main">
+            <directory>.</directory>
+            <exclude>vendor</exclude>
+        </testsuite>
+    </testsuites>
+</phpunit>