--- a/setup.py	Fri May 03 10:42:54 2019 +0200
+++ b/setup.py	Fri May 03 19:06:37 2019 +0200
@@ -26,6 +26,13 @@
 with open(os.path.join(pkg_root, "README.txt"), "rt") as rf:
     long_description = rf.read()
 
+yaml_requirements = [
+    "PyYAML>=3.0",
+]
+
+all_requirements = []
+all_requirements.extend(yaml_requirements)
+
 setup(
     name="ConfigMix",
     version=version,
@@ -58,5 +65,9 @@
         "Programming Language :: Python :: 3.6",
         "Topic :: Software Development :: Libraries :: Python Modules"
     ],
-    install_requires = ["PyYAML>=3.0"],
+    extras_require={
+        "yaml": yaml_requirements,
+        "all" : all_requirements,
+    },
+    tests_require=all_requirements,
 )