diff --git a/HowtoThumbor.md b/HowtoThumbor.md
index 15b68eda..add56f53 100644
--- a/HowtoThumbor.md
+++ b/HowtoThumbor.md
@@ -27,7 +27,18 @@ python-webcolors          |         |        |           |
 La procédure suivante fonctionne, a priori :
 
 ~~~
-apt install \
+# echo 'deb http://mirror.evolix.org/debian jessie-backports main' >>/etc/apt/sources.list
+# cat >/etc/apt/preferences.d/backports <<eof
+Package: *
+Pin: release n=jessie-backports
+Pin-Priority: 50
+
+Package: python-backports-abc python-pil python-tornado python-derpconf python-pexif python-schedule python-statsd
+Pin: release n=jessie-backports
+Pin-Priority: 999
+eof
+# apt update
+# apt install \
     libc6                     \
     python                    \
     libpython2.7-stdlib       \
@@ -40,25 +51,18 @@ apt install \
     python-six                \
     python-pkg-resources      \
     python-singledispatch     \
+    python-backports-abc      \
+    python-pil                \
+    python-tornado            \
+    python-derpconf           \
+    python-pexif              \
+    python-schedule           \
+    python-statsd             \
     python-opencv
-wget \
-    http://ftp.fr.debian.org/debian/pool/main/p/python-backports-abc/python-backports-abc_0.5-1~bpo8+1_all.deb \
-    http://ftp.fr.debian.org/debian/pool/main/p/pillow/python-pil_3.4.2-1~bpo8+1_amd64.deb                     \
-    http://ftp.fr.debian.org/debian/pool/main/p/python-tornado/python-tornado_4.4.3-1~bpo8+1_amd64.deb         \
-    http://ftp.fr.debian.org/debian/pool/main/d/derpconf/python-derpconf_0.8.0-1~bpo8+1_all.deb                \
-    http://ftp.fr.debian.org/debian/pool/main/p/pexif/python-pexif_0.15-1~bpo8+1_all.deb                       \
-    http://ftp.fr.debian.org/debian/pool/main/s/schedule/python-schedule_0.3.2-1~bpo8+1_all.deb                \
-    http://ftp.fr.debian.org/debian/pool/main/p/python-statsd/python-statsd_3.2.1-2~bpo8+1_all.deb             \
-    http://ftp.fr.debian.org/debian/pool/main/libt/libthumbor/python-libthumbor_1.3.2-1_all.deb                \
+# wget \
+    http://ftp.fr.debian.org/debian/pool/main/libt/libthumbor/python-libthumbor_1.3.2-1_all.deb \
     http://ftp.fr.debian.org/debian/pool/main/t/thumbor/thumbor_6.3.2-4_amd64.deb
-dpkg -i \
-    python-backports-abc_0.5-1~bpo8+1_all.deb \
-    python-pil_3.4.2-1~bpo8+1_amd64.deb       \
-    python-tornado_4.4.3-1~bpo8+1_amd64.deb   \
-    python-derpconf_0.8.0-1~bpo8+1_all.deb    \
-    python-pexif_0.15-1~bpo8+1_all.deb        \
-    python-schedule_0.3.2-1~bpo8+1_all.deb    \
-    python-statsd_3.2.1-2~bpo8+1_all.deb      \
-    python-libthumbor_1.3.2-1_all.deb         \
+# dpkg -i \
+    python-libthumbor_1.3.2-1_all.deb \
     thumbor_6.3.2-4_amd64.deb
 ~~~
\ No newline at end of file