diff --git a/README.md b/README.md
index 06850f3..3925017 100644
--- a/README.md
+++ b/README.md
@@ -1,8 +1,8 @@
-# ynh-dev - Yunohost dev environnement manager
+# ynh-dev - Yunohost dev environment manager
 
 Report issues here: https://github.com/yunohost/issues
 
-ynh-dev is a CLI tool to manage your local development environement for YunoHost. This allow you to develop on the various repository of the YunoHost project.
+ynh-dev is a CLI tool to manage your local development environment for YunoHost. This allow you to develop on the various repository of the YunoHost project.
 
 In particular, it allows :
 
@@ -25,33 +25,50 @@ Here is the development flow:
 2. Manage YunoHost's dev LXCs
 3. Developping on your host, and testing in the container
 
-### 1. Setup ynh-dev and the development environnement
+### 1. Setup ynh-dev and the development environment
 
 First you need to install the dependencies. ynh-dev essentially requires git, vagrant, and an LXC ecosystem.
 
 Please consider using the [latest Vagrant version from their website](https://www.vagrantup.com/downloads.html), distribution versions can include weird bugs that have been fixed upstream. If you still prefer to do that, here are the instructions:
 
-- Debian, Ubuntu, Mint
+The following commands should work on **Linux Mint 19** (and possibly on any Debian Stretch?) :
 
 ```bash
-sudo apt-get install vagrant virtualbox git
-```
-
-The following commands should work on Linux Mint 19 (and possibly on any Debian Stretch?) :
-
-```bash
-apt update
-apt install git vagrant lxc-templates lxctl lxc cgroup-lite redir bridge-utils libc6 debootstrap
+sudo apt update
+sudo apt install git vagrant lxc-templates lxctl lxc cgroup-lite redir bridge-utils libc6 debootstrap
 vagrant plugin install vagrant-lxc
 echo "cgroup        /sys/fs/cgroup        cgroup        defaults    0    0" | sudo tee -a /etc/fstab
 sudo mount /sys/fs/cgroup
-lxc-checkconfig 
+lxc-checkconfig
 echo "veth" | sudo tee -a /etc/modules
 ```
 
-If you run Archlinux, this page should be quite useful to setup LXC : https://github.com/fgrehm/vagrant-lxc/wiki/Usage-on-Arch-Linux-hosts
+On **Debian Buster**, I had to re-patch the driver.rb of vagrant-lxc plugin with [this version](https://raw.githubusercontent.com/fgrehm/vagrant-lxc/2a5510b34cc59cd3cb8f2dcedc3073852d841101/lib/vagrant-lxc/driver.rb) (especially the `roofs_path` function). I also had to install `apparmor` then `systemctl restart apparmor` for `lxc-start` to work. Also check instruction on https://feeding.cloud.geek.nz/posts/lxc-setup-on-debian-stretch/
 
-Then, go into your favorite development folder and deploy ynh-dev with : 
+If you run **Archlinux**, this page should be quite useful to setup LXC : https://github.com/fgrehm/vagrant-lxc/wiki/Usage-on-Arch-Linux-hosts
+
+On **both Debian and Archlinux**, typically `/etc/default/lxc-net` and `/etc/lxc/default.conf` should look like this :
+
+```
+ > cat /etc/default/lxc-net
+USE_LXC_BRIDGE="true"
+LXC_BRIDGE="lxcbr0"
+LXC_ADDR="10.0.3.1"
+LXC_NETMASK="255.255.255.0"
+LXC_NETWORK="10.0.3.0/24"
+LXC_DHCP_RANGE="10.0.3.2,10.0.3.254"
+LXC_DHCP_MAX="253"
+
+> cat /etc/lxc/default.conf
+lxc.net.0.type = veth
+lxc.net.0.link = lxcbr0
+lxc.net.0.flags = up
+lxc.net.0.hwaddr = 00:16:3e:xx:xx:xx
+```
+
+On **Debian Buster**, for backup stuff to work correctly with apparmor, I also had to add `mount options=(ro, remount, bind, rbind),` and `  mount options=(ro, remount, bind, relatime),` to `/etc/apparmor.d/lxc/lxc-default-cgns` and restart the apparmor service.
+
+Then, go into your favorite development folder and deploy ynh-dev with :
 
 ```bash
 curl https://raw.githubusercontent.com/yunohost/ynh-dev/master/deploy.sh | bash
@@ -66,6 +83,7 @@ When ran on the host, the `./ynh-dev` command allows you to manage YunoHost's de
 First, you might want to start a new LXC with :
 
 ```bash
+cd ynh-dev  # if not already done
 ./ynh-dev start
 ```
 
@@ -133,7 +151,7 @@ Depending on what you want to achieve, you might want to run the postinstall rig
 Deploy a `ynh-dev` folder at the root of the filesystem with :
 
 ```
-cd / 
+cd /
 curl https://raw.githubusercontent.com/yunohost/ynh-dev/master/deploy.sh | bash
 cd /ynh-dev
 ```
@@ -152,4 +170,4 @@ any `yunohost` command will run from the code of the git clone. The `use-git` ac
 
 ## More info
 
-[yunohost.org/dev_fr](https://yunohost.org/dev_fr) (in french) not up-to-date.
+* [yunohost.org/dev](https://yunohost.org/dev) not up-to-date.
diff --git a/prebuild/prebuild.sh b/prebuild/prebuild.sh
deleted file mode 100755
index 99aaeb7..0000000
--- a/prebuild/prebuild.sh
+++ /dev/null
@@ -1,19 +0,0 @@
-#!/bin/bash
-
-# Compute box name
-BOX="ynh-dev"
-
-# Create box
-vagrant up $BOX
-
-# Package box
-vagrant package $BOX --output /tmp/$BOX.box
-
-# Destroy current box
-vagrant destroy $BOX
-
-# User message, and exit
-echo ""
-echo "Your Vagrant box was packaged to /tmp/$BOX.box"
-echo "You might want to run : vagrant box add 'yunohost/ynh-dev' /tmp/$BOX.box"
-exit
diff --git a/ynh-dev b/ynh-dev
index e342f46..ff1a528 100755
--- a/ynh-dev
+++ b/ynh-dev
@@ -17,6 +17,8 @@ function show_usage() {
   ip              Give the ip of the guest container
   use-git [PKG]   Use Git repositories from dev environment path
   test [PKG]      Deploy, update and run tests for some packages
+                  Tests for single modules and functions can ran with
+                  e.g. ./ynh-dev test yunohost/appurl:urlavailable
 
 EOF
 }
@@ -109,8 +111,24 @@ function create_sym_link() {
 #               Actions                                          #
 ##################################################################
 
+function check_lxc_setup()
+{
+    local LXC_VERSION=$(lxc-info --version)
+
+    [[ "${LXC_VERSION:0:1}" == 3 ]] \
+        || critical "You need at least version 3 of LXC otherwise the box won't work"
+
+    [[ $(systemctl is-active lxc-net) == "active" ]] \
+        || critical "Service lxc-net should be running ... You probably need to fix your lxc network conf before being able to use lxc's."
+
+    ip a | grep -q lxcbr0 \
+        || critical "There is no 'lxcbr0' interface. You probably need to fix your lxc network conf before being able to use lxc's."
+}
+
 function start_ynhdev()
 {
+    check_lxc_setup
+
     local NAME=${1:-ynh-dev}
     local BOX_NAME="yunohost/ynh-dev"
     local BOX_URL="https://build.yunohost.org/yunohost-$BOX_NAME-lxc.box"
@@ -131,28 +149,33 @@ function start_ynhdev()
 
 function ssh_ynhdev()
 {
+    check_lxc_setup
     local NAME=${1:-ynh-dev}
     vagrant ssh $NAME -c "echo 'You are now inside the LXC !'; cd /ynh-dev; sudo su"
 }
 
 function destroy_ynhdev()
 {
+    check_lxc_setup
     local NAME=${1:-ynh-dev}
     vagrant destroy $NAME
 }
 
 function rebuild_ynhdev()
 {
+    check_lxc_setup
+
     local BOX="ynh-dev"
 
     set -x
     cd prebuild
 
     # Create box
-    vagrant up $BOX
+    vagrant up $BOX --provider=lxc --provision || critical "Could not create the box ?"
 
     # Package box
-    vagrant package $BOX --output /tmp/$BOX.box
+    rm -f /tmp/ynh-dev.box
+    vagrant package $BOX --output /tmp/$BOX.box || critical "Could not package package the box ?"
 
     # Destroy current box
     vagrant destroy $BOX
@@ -161,7 +184,7 @@ function rebuild_ynhdev()
 
     # User message, and exit
     info "The Vagrant box was packaged to /tmp/$BOX.box"
-    info "You might want to run : vagrant box add 'yunohost/ynh-dev' /tmp/$BOX.box"
+    info "You might want to run : vagrant box add 'yunohost/ynh-dev' /tmp/$BOX.box --force"
 }
 
 function show_vm_ip()
@@ -238,7 +261,7 @@ function use_git()
                     sudo apt install nodejs
 
                     cd /ynh-dev/yunohost-admin/src
-                    sudo npm install
+                    sudo npm install --no-bin-links
                     sudo npm install -g bower
                     sudo npm install -g gulp
                 fi
@@ -270,10 +293,14 @@ function run_tests()
     local PACKAGES="$@"
     for PACKAGE in "$PACKAGES";
     do
+        TEST_FUNCTION=$(echo "$PACKAGE" | tr '/:' ' ' | awk '{print $3}')
+        TEST_MODULE=$(echo "$PACKAGE" | tr '/:' ' ' | awk '{print $2}')
+        PACKAGE=$(echo "$PACKAGE" | tr '/:' ' ' | awk '{print $1}')
+
         case $PACKAGE in
             yunohost)
                 # Pytest and tests dependencies
-                if ! type "pytest" > /dev/null; then
+                if ! type "pytest" > /dev/null 2>&1; then
                     info "> Installing pytest ..."
                     apt-get install python-pip -y
                     pip2 install pytest
@@ -293,12 +320,23 @@ function run_tests()
                 git pull > /dev/null 2>&1
 
                 # Run tests
-                info "Running tests for YunoHost ..."
+                info "Running tests for YunoHost"
                 [ -e "/etc/yunohost/installed" ] || critical "You should run postinstallation before running tests :s."
-                cd /ynh-dev/yunohost/
-                py.test tests
-                cd /ynh-dev/yunohost/src/yunohost
-                py.test tests
+                if [[ -z "$TEST_MODULE" ]]
+                then
+                    cd /ynh-dev/yunohost/
+                    py.test tests
+                    cd /ynh-dev/yunohost/src/yunohost
+                    py.test tests
+                else
+                    cd /ynh-dev/yunohost/src/yunohost
+                    if [[ -z "$TEST_FUNCTION" ]]
+                    then
+                        py.test tests/test_"$TEST_MODULE".py
+                    else
+                        py.test tests/test_"$TEST_MODULE".py::test_"$TEST_FUNCTION"
+                    fi
+                fi
                 ;;
         esac
     done