diff --git a/scripts/_common.sh b/scripts/_common.sh
index 7a693aa..0f16e79 100644
--- a/scripts/_common.sh
+++ b/scripts/_common.sh
@@ -1,3 +1,122 @@
 #!/bin/bash
 
+# LOCAL ADDITION:
+# save file locally if not in the cache
+#
+# Download, check integrity, uncompress and patch the source from app.src
+#
+# The file conf/app.src need to contains:
+#
+# SOURCE_URL=Address to download the app archive
+# SOURCE_SUM=Control sum
+# # (Optional) Program to check the integrity (sha256sum, md5sum...)
+# # default: sha256
+# SOURCE_SUM_PRG=sha256
+# # (Optional) Archive format
+# # default: tar.gz
+# SOURCE_FORMAT=tar.gz
+# # (Optional) Put false if sources are directly in the archive root
+# # default: true
+# SOURCE_IN_SUBDIR=false
+# # (Optionnal) Name of the local archive (offline setup support)
+# # default: ${src_id}.${src_format}
+# SOURCE_FILENAME=example.tar.gz
+#
+# Details:
+# This helper downloads sources from SOURCE_URL if there is no local source
+# archive in /opt/yunohost-apps-src/APP_ID/SOURCE_FILENAME
+#
+# Next, it checks the integrity with "SOURCE_SUM_PRG -c --status" command.
+#
+# If it's ok, the source archive will be uncompressed in $dest_dir. If the
+# SOURCE_IN_SUBDIR is true, the first level directory of the archive will be
+# removed.
+#
+# Finally, patches named sources/patches/${src_id}-*.patch and extra files in
+# sources/extra_files/$src_id will be applied to dest_dir
+#
+#
+# usage: ynh_setup_source dest_dir [source_id]
+# | arg: dest_dir  - Directory where to setup sources
+# | arg: source_id - Name of the app, if the package contains more than one app
+ynh_setup_source_local () {
+    local dest_dir=$1
+    local src_id=${2:-app} # If the argument is not given, source_id equals "app"
 
+    # Load value from configuration file (see above for a small doc about this file
+    # format)
+    local src_url=$(grep 'SOURCE_URL=' "$YNH_CWD/../conf/${src_id}.src" | cut -d= -f2-)
+    local src_sum=$(grep 'SOURCE_SUM=' "$YNH_CWD/../conf/${src_id}.src" | cut -d= -f2-)
+    local src_sumprg=$(grep 'SOURCE_SUM_PRG=' "$YNH_CWD/../conf/${src_id}.src" | cut -d= -f2-)
+    local src_format=$(grep 'SOURCE_FORMAT=' "$YNH_CWD/../conf/${src_id}.src" | cut -d= -f2-)
+    local src_in_subdir=$(grep 'SOURCE_IN_SUBDIR=' "$YNH_CWD/../conf/${src_id}.src" | cut -d= -f2-)
+    local src_filename=$(grep 'SOURCE_FILENAME=' "$YNH_CWD/../conf/${src_id}.src" | cut -d= -f2-)
+
+    # Default value
+    src_sumprg=${src_sumprg:-sha256sum}
+    src_in_subdir=${src_in_subdir:-true}
+    src_format=${src_format:-tar.gz}
+    src_format=$(echo "$src_format" | tr '[:upper:]' '[:lower:]')
+    if [ "$src_filename" = "" ] ; then
+        src_filename="${src_id}.${src_format}"
+    fi
+    local local_src="/var/cache/yunohost/ynh_setup_source/${YNH_APP_ID}/${src_filename}"
+
+    # if cache file exists and the checksum isn't good, download it again
+    # if not, just download the file
+
+    if test -e "$local_src"
+    then
+    	echo "${src_sum} ${local_src}" | ${src_sumprg} -c --status \
+        	|| wget -nv -O $local_src $src_url
+    else
+    	mkdir -p "/var/cache/yunohost/ynh_setup_source/${YNH_APP_ID}"
+    	wget -nv -O $local_src $src_url
+    fi
+    cp $local_src $src_filename
+
+    # Check the control sum
+    echo "${src_sum} ${src_filename}" | ${src_sumprg} -c --status \
+        || ynh_die "Corrupt source"
+
+    # Extract source into the app dir
+    mkdir -p "$dest_dir"
+    if [ "$src_format" = "zip" ]
+    then
+        # Zip format
+        # Using of a temp directory, because unzip doesn't manage --strip-components
+        if $src_in_subdir ; then
+            local tmp_dir=$(mktemp -d)
+            unzip -quo $src_filename -d "$tmp_dir"
+            cp -a $tmp_dir/*/. "$dest_dir"
+            ynh_secure_remove "$tmp_dir"
+        else
+            unzip -quo $src_filename -d "$dest_dir"
+        fi
+    else
+        local strip=""
+        if $src_in_subdir ; then
+            strip="--strip-components 1"
+        fi
+        if [[ "$src_format" =~ ^tar.gz|tar.bz2|tar.xz$ ]] ; then
+            tar -xf $src_filename -C "$dest_dir" $strip
+        else
+            ynh_die "Archive format unrecognized."
+        fi
+    fi
+
+    # Apply patches
+    if (( $(find $YNH_CWD/../sources/patches/ -type f -name "${src_id}-*.patch" 2> /dev/null | wc -l) > "0" )); then
+        local old_dir=$(pwd)
+        (cd "$dest_dir" \
+            && for p in $YNH_CWD/../sources/patches/${src_id}-*.patch; do \
+                patch -p1 < $p; done) \
+            || ynh_die "Unable to apply patches"
+        cd $old_dir
+    fi
+
+    # Add supplementary files
+    if test -e "$YNH_CWD/../sources/extra_files/${src_id}"; then
+        cp -a $YNH_CWD/../sources/extra_files/$src_id/. "$dest_dir"
+    fi
+}
diff --git a/scripts/install b/scripts/install
index 3139491..8d711e9 100644
--- a/scripts/install
+++ b/scripts/install
@@ -79,7 +79,7 @@ ynh_mysql_setup_db "$db_user" "$db_name"
 #=================================================
 
 # Download, check integrity, uncompress and patch the source from app.src
-ynh_setup_source "$final_path"
+ynh_setup_source_local "$final_path"
 
 # Modify assets to take path into account
 # TODO: try to include this as a patch if still needed
@@ -149,13 +149,24 @@ ynh_replace_string "__DB_NAME__"   "$db_name" "$final_path/syncserver.ini"
 # ynh_replace_string "media\/img@$path_url\/media\/img@g" $final_path/syncserver/page/sync_files/responsive-bundle.css
 
 #=================================================
-# make
+# pip installation
 #=================================================
 
+virtualenv "$final_path/local"
 # Init virtualenv
 (
+	set +o nounset
+	source "$final_path/local/bin/activate"
+	set -o nounset
 	cd "$final_path"
-	make build
+	pip install --upgrade pip
+	CFLAGS="-Wno-error -Wno-error=format-security" \
+		ARCHFLAGS="-Wno-error=unused-command-line-argument-hard-error-in-future" \
+		pip install --requirement "$final_path/requirements.txt"
+
+	python "$final_path/setup.py" develop
+
+	touch "$final_path/local/COMPLETE"
 )
 
 #=================================================
diff --git a/scripts/upgrade b/scripts/upgrade
index 7a61628..8c64704 100644
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -101,7 +101,7 @@ ynh_install_app_dependencies make python-dev python-virtualenv \
 #=================================================
 
 # Download, check integrity, uncompress and patch the source from app.src
-ynh_setup_source "$final_path"
+ynh_setup_source_local "$final_path"
 
 #=================================================
 # NGINX CONFIGURATION