diff --git a/component/python-cryptography/buildout.cfg b/component/python-cryptography/buildout.cfg
index b1f8ca604b6fb840e0c1a8ee037da1d83d3e36c3..0a61c5ddfef33b6a1fc2bb5fadfce131dbd05d6c 100644
--- a/component/python-cryptography/buildout.cfg
+++ b/component/python-cryptography/buildout.cfg
@@ -14,6 +14,6 @@ environment = python-cryptography-env
 
 [python-cryptography-env]
 PATH = ${pkgconfig:location}/bin:%(PATH)s
-PKG_CONFIG_PATH = ${libffi:location}/lib/pkgconfig
-LD_LIBRARY_PATH = ${libffi:location}/lib
-CPATH = ${openssl:location}/include
+PKG_CONFIG_PATH = ${libffi:location}/lib/pkgconfig:${openssl:location}/lib/pkgconfig
+LD_LIBRARY_PATH = ${libffi:location}/lib:${openssl:location}/lib
+CPATH = ${libffi:location}/include:${openssl:location}/include
diff --git a/software/backupserver/software.cfg b/software/backupserver/software.cfg
index d9e332a69532eb6f8fa7f0b1d041c7847cf4ea5a..5af5bc8383bd4c18444cea0afca2a45b959e1440 100644
--- a/software/backupserver/software.cfg
+++ b/software/backupserver/software.cfg
@@ -1,5 +1,9 @@
 [buildout]
 extends =
+  ../../component/lxml-python/buildout.cfg
+  ../../component/python-2.7/buildout.cfg
+  ../../component/python-cffi/buildout.cfg
+  ../../component/python-cryptography/buildout.cfg
   ../../component/dash/buildout.cfg
   ../../component/dcron/buildout.cfg
   ../../component/logrotate/buildout.cfg
@@ -37,9 +41,19 @@ parts =
 [extra-eggs]
 recipe = zc.recipe.egg
 interpreter = pythonforrssgen
+python = python2.7
 eggs =
   PyRSS2Gen
 
+[lxml-python]
+python = python2.7
+
+[python-cffi]
+python = python2.7
+
+[python-cryptography]
+python = python2.7
+
 [networkcache]
 # signature certificates of the following uploaders.
 #   Romain Courteaud