diff --git a/.travis.yml b/.travis.yml
index 3eb7b32..e43ddc3 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -2,16 +2,23 @@ language: bash
 
 sudo: required
 
+env:
+  - TRAVIS_BASH_VERSION="4.0"
+
+before_install:
+  - ./tests/integ-tests/install-bash.sh "$TRAVIS_BASH_VERSION"
+
 install:
-    - PATH=$PWD/bin:$PATH
-    - junest -- echo "Installing JuNest (\$(uname -m))"
-    - JUNEST_HOME=~/.junest-arm junest -a arm -- echo "Installing JuNest (\$(uname -m))"
-    # TODO: Remember to enable x86 tests when fixed
-    #- JUNEST_HOME=~/.junest-x86 junest -a x86 -- echo "Installing JuNest (\$(uname -m))"
+  - PATH=$PWD/bin:$PATH
+  - junest -- echo "Installing JuNest (\$(uname -m))"
+  - JUNEST_HOME=~/.junest-arm junest -a arm -- echo "Installing JuNest (\$(uname -m))"
+  # TODO: Remember to enable x86 tests when fixed
+  #- JUNEST_HOME=~/.junest-x86 junest -a x86 -- echo "Installing JuNest (\$(uname -m))"
 
 script:
-    - ./tests/unit-tests.sh
-    - junest --check ./bin/junest
-    - yes | junest --delete
-    - JUNEST_HOME=~/.junest-arm junest --check ./bin/junest --skip-root-tests
-    - yes | JUNEST_HOME=~/.junest-arm junest --delete
+  - bash --version
+  - ./tests/unit-tests/unit-tests.sh
+  - junest --check ./bin/junest
+  - yes | junest --delete
+  - JUNEST_HOME=~/.junest-arm junest --check ./bin/junest --skip-root-tests
+  - yes | JUNEST_HOME=~/.junest-arm junest --delete
diff --git a/LICENSE b/LICENSE
index 6b156fe..610ce97 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,4 +1,6 @@
-GNU GENERAL PUBLIC LICENSE
+
+
+                    GNU GENERAL PUBLIC LICENSE
                        Version 3, 29 June 2007
 
  Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
@@ -631,8 +633,8 @@ to attach them to the start of each source file to most effectively
 state the exclusion of warranty; and each file should have at least
 the "copyright" line and a pointer to where the full notice is found.
 
-    {one line to give the program's name and a brief idea of what it does.}
-    Copyright (C) {year}  {name of author}
+    JuNest: The Arch Linux based distro that runs upon any Linux distros without root access
+    Copyright (C) 2014 Filippo Squillace
 
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -652,7 +654,7 @@ Also add information on how to contact you by electronic and paper mail.
   If the program does terminal interaction, make it output a short
 notice like this when it starts in an interactive mode:
 
-    {project}  Copyright (C) {year}  {fullname}
+    JuNest  Copyright (C) 2014 Filippo Squillace
     This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
     This is free software, and you are welcome to redistribute it
     under certain conditions; type `show c' for details.
@@ -673,3 +675,4 @@ the library.  If this is what you want to do, use the GNU Lesser General
 Public License instead of this License.  But first, please read
 <http://www.gnu.org/philosophy/why-not-lgpl.html>.
 
+
diff --git a/README.md b/README.md
index 8f7a22e..ef21b49 100644
--- a/README.md
+++ b/README.md
@@ -58,14 +58,22 @@ visit the [pacman rosetta page](https://wiki.archlinux.org/index.php/Pacman_Rose
 
 Installation
 ============
-JuNest can works on GNU/Linux OS with kernel version greater or equal
-2.6.0 (JuNest was not tested on kernel versions older than this) on 64 bit, 32 bit and ARM architectures.
+
+## Dependencies ##
+JuNest comes with a very short list of dependencies in order to be installed in most
+of GNU/Linux distributions.
+Before installing JuNest be sure that all dependencies are properly installed in your system:
+
+- [bash (>=4.0)](https://www.gnu.org/software/bash/)
+- [GNU coreutils](https://www.gnu.org/software/coreutils/)
+
+The minimum recommended Linux kernel is 2.6.0+ on x86 32 and 64 bit and ARM architectures.
 
 ## Method one (Recommended) ##
-Just clone the JuNest repo somewhere (for example in ~/junest):
+Just clone the JuNest repo somewhere (for example in ~/.local/share/junest):
 
-    git clone git://github.com/fsquillace/junest ~/junest
-    export PATH=~/junest/bin:$PATH
+    git clone git://github.com/fsquillace/junest ~/.local/share/junest
+    export PATH=~/.local/share/junest/bin:$PATH
 
 ### Installation using AUR (Arch Linux only) ###
 If you are using an Arch Linux system you can, alternatively, install JuNest from the [AUR repository](https://aur.archlinux.org/):
@@ -81,22 +89,6 @@ Alternatively, another installation method would be to directly download the JuN
     curl https://dl.dropboxusercontent.com/u/42449030/junest/junest-${ARCH}.tar.gz | tar -xz -C ~/.junest
     export PATH=~/.junest/opt/junest/bin:$PATH
 
-Dependencies
-============
-JuNest comes with a very short list of dependencies in order to be installed in most
-of GNU/Linux distributions. The needed executables in the host OS are:
-
-- bash
-- chown (for root access only)
-- ln
-- mkdir
-- rm
-- tar
-- uname
-- wget or curl
-
-The minimum recommended linux kernel is 2.6.0+
-
 Advanced usage
 ==============
 
diff --git a/VERSION b/VERSION
new file mode 100644
index 0000000..b3ae5c7
--- /dev/null
+++ b/VERSION
@@ -0,0 +1 @@
+5.6.7
diff --git a/bin/jchroot b/bin/jchroot
index 98f8680..8eaa8d4 100755
--- a/bin/jchroot
+++ b/bin/jchroot
@@ -1,30 +1,14 @@
 #!/bin/bash
 #
-# This file is part of JuNest (https://github.com/fsquillace/junest)
-#
-# Copyright (c) 2015
-#
-# This program is free software; you can redistribute it and/or modify it
-# under the terms of the GNU Library General Public License as published
-# by the Free Software Foundation; either version 2, or (at your option)
-# any later version.
-#
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with this program.  If not, see <http://www.gnu.org/licenses/>.
-#
-
 # This script is the simplified and portable version of arch-chroot
 # (https://wiki.archlinux.org/index.php/Change_root#Using_arch-chroot)
+#
 
 set -e
 
-################################ IMPORTS ##################################
-source "$(dirname $0)/../lib/util.sh"
+JUNEST_BASE="$(readlink -f $(dirname $(readlink -f "$0"))/..)"
+
+source "${JUNEST_BASE}/lib/utils.sh"
 
 ################################ MAIN FUNCTIONS ###########################
 
diff --git a/bin/junest b/bin/junest
index 9ac3736..530a759 100755
--- a/bin/junest
+++ b/bin/junest
@@ -2,24 +2,10 @@
 #
 # This file is part of JuNest (https://github.com/fsquillace/junest).
 #
-# Copyright (c) 2015
-#
-# This program is free software; you can redistribute it and/or modify it
-# under the terms of the GNU Library General Public License as published
-# by the Free Software Foundation; either version 2, or (at your option)
-# any later version.
-#
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with this program.  If not, see <http://www.gnu.org/licenses/>.
-#
 
-JUNEST_BASE="$(dirname $0)/.."
+JUNEST_BASE="$(readlink -f $(dirname $(readlink -f "$0"))/..)"
 
+source "${JUNEST_BASE}/lib/utils.sh"
 source "${JUNEST_BASE}/lib/core.sh"
 
 ###################################
@@ -27,9 +13,10 @@ source "${JUNEST_BASE}/lib/core.sh"
 ###################################
 
 usage() {
-    echo -e "$NAME: $DESCRIPTION"
+    echo -e "$NAME (v$(cat $JUNEST_BASE/VERSION)): $DESCRIPTION"
+    echo
     echo -e "Usage: $CMD [options] [--] [command]"
-	echo
+    echo
     echo -e "Setup options:"
     echo -e "-i, --setup-from-file <image>  Setup the $NAME image in ${JUNEST_HOME}"
     echo -e "-a, --arch <arch>              $NAME architecture to download (x86_64, x86, arm)."
@@ -54,9 +41,7 @@ usage() {
 }
 
 version() {
-	echo -e "$NAME $VERSION ($CODE_NAME): $DESCRIPTION"
-    echo -e "Copyright (c) $COPYRIGHT $AUTHOR"
-    echo -e "Homepage: $HOMEPAGE"
+    echo -e "$NAME $(cat $JUNEST_BASE/VERSION)"
 }
 
 check_cli(){
@@ -142,90 +127,94 @@ check_cli(){
 
 
 function parse_arguments(){
-	OPT_SETUP_FROM_FILE=false
-	IMAGE_FILE=""
-	OPT_FAKEROOT=false
-	OPT_ROOT=false
-	OPT_PROOT_ARGS=false
-	PROOT_ARGS=""
-	OPT_ARCH=false
-	ARCH_ARG=""
-	OPT_BUILD_IMAGE=false
-	OPT_DISABLE_VALIDATION=false
-	OPT_CHECK=false
-	CHECK_ARG=""
-	OPT_SKIP_ROOT_TEST=false
-	OPT_DELETE=false
-	OPT_HELP=false
-	OPT_VERSION=false
-	for opt in "$@"
-	do
-		case "$1" in
-			-i|--setup-from-file) OPT_SETUP_FROM_FILE=true ; shift ; IMAGE_FILE=$1 ; shift ;;
-			-f|--fakeroot) OPT_FAKEROOT=true ; shift ;;
-			-r|--root) OPT_ROOT=true ; shift ;;
-			-p|--proot-args) OPT_PROOT_ARGS=true ; shift ; PROOT_ARGS=$1; shift ;;
-			-a|--arch) OPT_ARCH=true ; shift ; ARCH_ARG=$1; shift ;;
-			-b|--build-image) OPT_BUILD_IMAGE=true ; shift ;;
-			-n|--disable-validation) OPT_DISABLE_VALIDATION=true ; shift ;;
-			-c|--check) OPT_CHECK=true ; shift ; CHECK_ARG=$1; shift ;;
-			-s|--skip-root-tests) OPT_SKIP_ROOT_TEST=true ; shift ;;
-			-d|--delete) OPT_DELETE=true ; shift ;;
-			-h|--help) OPT_HELP=true ; shift ;;
-			-v|--version) OPT_VERSION=true ; shift ;;
-			--) shift ; break ;;
-			-*) die "Invalid option $1" ;;
-			*) break ;;
-		esac
-	done
+    OPT_SETUP_FROM_FILE=false
+    IMAGE_FILE=""
+    OPT_FAKEROOT=false
+    OPT_ROOT=false
+    OPT_PROOT_ARGS=false
+    PROOT_ARGS=""
+    OPT_ARCH=false
+    ARCH_ARG=""
+    OPT_BUILD_IMAGE=false
+    OPT_DISABLE_VALIDATION=false
+    OPT_CHECK=false
+    CHECK_ARG=""
+    OPT_SKIP_ROOT_TEST=false
+    OPT_DELETE=false
+    OPT_HELP=false
+    OPT_VERSION=false
+    for opt in "$@"
+    do
+        case "$1" in
+            -i|--setup-from-file) OPT_SETUP_FROM_FILE=true ; shift ; IMAGE_FILE=$1 ; shift ;;
+            -f|--fakeroot) OPT_FAKEROOT=true ; shift ;;
+            -r|--root) OPT_ROOT=true ; shift ;;
+            -p|--proot-args) OPT_PROOT_ARGS=true ; shift ; PROOT_ARGS=$1; shift ;;
+            -a|--arch) OPT_ARCH=true ; shift ; ARCH_ARG=$1; shift ;;
+            -b|--build-image) OPT_BUILD_IMAGE=true ; shift ;;
+            -n|--disable-validation) OPT_DISABLE_VALIDATION=true ; shift ;;
+            -c|--check) OPT_CHECK=true ; shift ; CHECK_ARG=$1; shift ;;
+            -s|--skip-root-tests) OPT_SKIP_ROOT_TEST=true ; shift ;;
+            -d|--delete) OPT_DELETE=true ; shift ;;
+            -h|--help) OPT_HELP=true ; shift ;;
+            -v|--version) OPT_VERSION=true ; shift ;;
+            --) shift ; break ;;
+            -*) die "Invalid option $1" ;;
+            *) break ;;
+        esac
+    done
 
-	ARGS=()
-	for arg in "$@"
-	do
-		ARGS+=("$arg")
-	done
+    ARGS=()
+    for arg in "$@"
+    do
+        ARGS+=("$arg")
+    done
 }
 
 function execute_operation(){
-	$OPT_HELP && usage && return
-	$OPT_VERSION && version && return
+    $OPT_HELP && usage && return
+    $OPT_VERSION && version && return
 
-	if $OPT_BUILD_IMAGE; then
-		build_image_env $OPT_DISABLE_VALIDATION $OPT_SKIP_ROOT_TEST
-		return
-	elif $OPT_DELETE; then
-		delete_env
-		return
-	elif $OPT_CHECK; then
-		check_env "${JUNEST_HOME}" "${CHECK_ARG}" $OPT_SKIP_ROOT_TEST
-		return
-	fi
+    if $OPT_BUILD_IMAGE; then
+        build_image_env $OPT_DISABLE_VALIDATION $OPT_SKIP_ROOT_TEST
+        return
+    elif $OPT_DELETE; then
+        delete_env
+        return
+    elif $OPT_CHECK; then
+        check_env "${JUNEST_HOME}" "${CHECK_ARG}" $OPT_SKIP_ROOT_TEST
+        return
+    fi
 
-	if ! is_env_installed
-	then
-		if $OPT_SETUP_FROM_FILE; then
-			setup_env_from_file $IMAGE_FILE
-		else
-			setup_env $ARCH_ARG
-			unset ARCH_ARG
-		fi
-	elif $OPT_SETUP_FROM_FILE; then
-		die "Error: The image cannot be installed since $JUNEST_HOME is not empty."
-	fi
+    if ! is_env_installed
+    then
+        if $OPT_SETUP_FROM_FILE; then
+            setup_env_from_file $IMAGE_FILE
+        else
+            setup_env $ARCH_ARG
+            unset ARCH_ARG
+        fi
+    elif $OPT_SETUP_FROM_FILE; then
+        die "Error: The image cannot be installed since $JUNEST_HOME is not empty."
+    fi
 
-	[ -z "${ARCH_ARG}" ] || \
-		die "The option --arch cannot be specified since JuNest has already been downloaded in $JUNEST_HOME"
+    [ -z "${ARCH_ARG}" ] || \
+        die "The option --arch cannot be specified since JuNest has already been downloaded in $JUNEST_HOME"
 
-	if $OPT_FAKEROOT; then
-		run_env_as_fakeroot "${PROOT_ARGS}" "${ARGS[@]}"
-	elif $OPT_ROOT; then
-		run_env_as_root "${ARGS[@]}"
-	else
-		run_env_as_user "${PROOT_ARGS}" "${ARGS[@]}"
-	fi
+    if $OPT_FAKEROOT; then
+        run_env_as_fakeroot "${PROOT_ARGS}" "${ARGS[@]}"
+    elif $OPT_ROOT; then
+        run_env_as_root "${ARGS[@]}"
+    else
+        run_env_as_user "${PROOT_ARGS}" "${ARGS[@]}"
+    fi
 }
 
-parse_arguments "$@"
-check_cli
-execute_operation
+function cli() {
+    parse_arguments "$@"
+    check_cli
+    execute_operation
+}
+
+cli "$@"
 # vim: set ts=4 sw=4 noet:
diff --git a/lib/core.sh b/lib/core.sh
index 4cd08f0..7012391 100644
--- a/lib/core.sh
+++ b/lib/core.sh
@@ -1,48 +1,31 @@
 #!/usr/bin/env bash
 #
-# Copyright (c) 2015
+# This module contains all core functionalities for JuNest.
 #
-# This program is free software; you can redistribute it and/or modify it
-# under the terms of the GNU Library General Public License as published
-# by the Free Software Foundation; either version 2, or (at your option)
-# any later version.
+# Dependencies:
+# - lib/utils.sh
 #
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with this program.  If not, see <http://www.gnu.org/licenses/>.
-#
-
-# References:
-# https://wiki.archlinux.org/index.php/PKGBUILD
-# https://wiki.archlinux.org/index.php/Creating_Packages
+# vim: ft=sh
 
 set -e
 
-################################ IMPORTS #################################
-source "$(dirname ${BASH_ARGV[0]})/util.sh"
-
-################################# VARIABLES ##############################
-
 NAME='JuNest'
 CMD='junest'
-VERSION='5.6.7'
-CODE_NAME='Nitida'
 DESCRIPTION='The Arch Linux based distro that runs upon any Linux distros without root access'
-AUTHOR='Filippo Squillace <feel dot sqoox at gmail.com>'
-HOMEPAGE="https://github.com/fsquillace/${CMD}"
-COPYRIGHT='2012-2016'
 
+NOT_AVAILABLE_ARCH=102
+NOT_EXISTING_FILE=103
+ARCHITECTURE_MISMATCH=104
+ROOT_ACCESS_ERROR=105
+NESTED_ENVIRONMENT=106
+VARIABLE_NOT_SET=107
 
 if [ "$JUNEST_ENV" == "1" ]
 then
-    die "Error: Nested ${NAME} environments are not allowed"
+    die_on_status $NESTED_ENVIRONMENT "Error: Nested ${NAME} environments are not allowed"
 elif [ ! -z $JUNEST_ENV ] && [ "$JUNEST_ENV" != "0" ]
 then
-    die "The variable JUNEST_ENV is not properly set"
+    die_on_status $VARIABLE_NOT_SET "The variable JUNEST_ENV is not properly set"
 fi
 
 [ -z ${JUNEST_HOME} ] && JUNEST_HOME=~/.${CMD}
@@ -101,6 +84,9 @@ WGET="wget --no-check-certificate"
 CURL="curl -L -J -O -k"
 TAR=tar
 CHOWN="chown"
+LN=ln
+RM=rm
+MKDIR=mkdir
 
 LD_EXEC="$LD_LIB --library-path ${JUNEST_HOME}/usr/lib:${JUNEST_HOME}/lib"
 
@@ -109,19 +95,19 @@ LD_EXEC="$LD_LIB --library-path ${JUNEST_HOME}/usr/lib:${JUNEST_HOME}/lib"
 # image.
 
 function ln_cmd(){
-    ln $@ || $LD_EXEC ${JUNEST_HOME}/usr/bin/ln $@
+    $LN $@ || $LD_EXEC ${JUNEST_HOME}/usr/bin/$LN $@
 }
 
 function rm_cmd(){
-    rm $@ || $LD_EXEC ${JUNEST_HOME}/usr/bin/rm $@
+    $RM $@ || $LD_EXEC ${JUNEST_HOME}/usr/bin/$RM $@
 }
 
 function chown_cmd(){
-    $CHOWN $@ || $LD_EXEC ${JUNEST_HOME}/usr/bin/chown $@
+    $CHOWN $@ || $LD_EXEC ${JUNEST_HOME}/usr/bin/$CHOWN $@
 }
 
 function mkdir_cmd(){
-    mkdir $@ || $LD_EXEC ${JUNEST_HOME}/usr/bin/mkdir $@
+    $MKDIR $@ || $LD_EXEC ${JUNEST_HOME}/usr/bin/$MKDIR $@
 }
 
 function proot_cmd(){
@@ -148,6 +134,19 @@ function chroot_cmd(){
 
 ################################# MAIN FUNCTIONS ##############################
 
+#######################################
+# Check if the JuNest system is installed in JUNEST_HOME.
+#
+# Globals:
+#   JUNEST_HOME (RO)  : Contains the JuNest home directory.
+# Arguments:
+#   None
+# Returns:
+#   0                 : If JuNest is installed
+#   1                 : If JuNest is not installed
+# Output:
+#   None
+#######################################
 function is_env_installed(){
     [ -d "$JUNEST_HOME" ] && [ "$(ls -A $JUNEST_HOME)" ] && return 0
     return 1
@@ -155,8 +154,8 @@ function is_env_installed(){
 
 
 function _cleanup_build_directory(){
-# $1: maindir (optional) - str: build directory to get rid
     local maindir=$1
+    check_not_null "$maindir"
     builtin cd $ORIGIN_WD
     trap - QUIT EXIT ABRT KILL TERM INT
     rm_cmd -fr "$maindir"
@@ -164,17 +163,21 @@ function _cleanup_build_directory(){
 
 
 function _prepare_build_directory(){
+    local maindir=$1
+    check_not_null "$maindir"
     trap - QUIT EXIT ABRT KILL TERM INT
     trap "rm_cmd -rf ${maindir}; die \"Error occurred when installing ${NAME}\"" EXIT QUIT ABRT KILL TERM INT
 }
 
 
 function _setup_env(){
+    local imagepath=$1
+    check_not_null "$imagepath"
+
     is_env_installed && die "Error: ${NAME} has been already installed in $JUNEST_HOME"
+
     mkdir_cmd -p "${JUNEST_HOME}"
-    imagepath=$1
     $TAR -zxpf ${imagepath} -C ${JUNEST_HOME}
-    mkdir_cmd -p ${JUNEST_HOME}/run/lock
     info "The default mirror URL is ${DEFAULT_MIRROR}."
     info "Remember to refresh the package databases from the server:"
     info "    pacman -Syy"
@@ -182,14 +185,33 @@ function _setup_env(){
 }
 
 
+#######################################
+# Setup JuNest.
+#
+# Globals:
+#   JUNEST_HOME (RO)      : The JuNest home directory in which JuNest needs
+#                           to be installed.
+#   ARCH (RO)             : The host architecture.
+#   JUNEST_TEMPDIR (RO)   : The JuNest temporary directory for building
+#                           the JuNest system from the image.
+#   ENV_REPO (RO)         : URL of the site containing JuNest images.
+#   NAME (RO)             : The JuNest name.
+#   DEFAULT_MIRROR (RO)   : Arch Linux URL mirror.
+# Arguments:
+#   arch ($1?)            : The JuNest architecture image to download.
+#                           Defaults to the host architecture
+# Returns:
+#   $NOT_AVAILABLE_ARCH   : If the architecture is not one of the available ones.
+# Output:
+#   None
+#######################################
 function setup_env(){
-    local arch=$ARCH
-    [ -z $1 ] || arch="$1"
+    local arch=${1:-$ARCH}
     contains_element $arch "${ARCH_LIST[@]}" || \
-        die "The architecture is not one of: ${ARCH_LIST[@]}"
+        die_on_status $NOT_AVAILABLE_ARCH "The architecture is not one of: ${ARCH_LIST[@]}"
 
     local maindir=$(TMPDIR=$JUNEST_TEMPDIR mktemp -d -t ${CMD}.XXXXXXXXXX)
-    _prepare_build_directory
+    _prepare_build_directory $maindir
 
     info "Downloading ${NAME}..."
     builtin cd ${maindir}
@@ -202,21 +224,51 @@ function setup_env(){
     _cleanup_build_directory ${maindir}
 }
 
-
+#######################################
+# Setup JuNest from file.
+#
+# Globals:
+#   JUNEST_HOME (RO)      : The JuNest home directory in which JuNest needs
+#                           to be installed.
+#   NAME (RO)             : The JuNest name.
+#   DEFAULT_MIRROR (RO)   : Arch Linux URL mirror.
+# Arguments:
+#   imagefile ($1)        : The JuNest image file.
+# Returns:
+#   $NOT_EXISTING_FILE    : If the image file does not exist.
+# Output:
+#   None
+#######################################
 function setup_env_from_file(){
     local imagefile=$1
-    [ ! -e ${imagefile} ] && die "Error: The ${NAME} image file ${imagefile} does not exist"
+    check_not_null "$imagefile"
+    [ ! -e ${imagefile} ] && die_on_status $NOT_EXISTING_FILE "Error: The ${NAME} image file ${imagefile} does not exist"
 
     info "Installing ${NAME} from ${imagefile}..."
     _setup_env ${imagefile}
-
-    builtin cd $ORIGIN_WD
 }
 
+#######################################
+# Run JuNest as real root.
+#
+# Globals:
+#   JUNEST_HOME (RO)         : The JuNest home directory.
+#   UID (RO)                 : The user ID.
+#   SUDO_USER (RO)           : The sudo user ID.
+#   SUDO_GID (RO)            : The sudo group ID.
+#   SH (RO)                  : Contains the default command to run in JuNest.
+# Arguments:
+#   cmd ($@?)                : The command to run inside JuNest environment.
+#                              Default command is defined by SH variable.
+# Returns:
+#   $ARCHITECTURE_MISMATCH   : If host and JuNest architecture are different.
+# Output:
+#   -                        : The command output.
+#######################################
 function run_env_as_root(){
     source ${JUNEST_HOME}/etc/junest/info
     [ "$JUNEST_ARCH" != "$ARCH" ] && \
-        die "The host system architecture is not correct: $ARCH != $JUNEST_ARCH"
+        die_on_status $ARCHITECTURE_MISMATCH "The host system architecture is not correct: $ARCH != $JUNEST_ARCH"
 
     local uid=$UID
     # SUDO_USER is more reliable compared to SUDO_UID
@@ -227,11 +279,7 @@ function run_env_as_root(){
 
     # With chown the ownership of the files is assigned to the real user
     trap - QUIT EXIT ABRT KILL TERM INT
-    trap "[ -z $uid ] || chown_cmd -R ${uid} ${JUNEST_HOME}; rm_cmd -f ${JUNEST_HOME}/etc/mtab" EXIT QUIT ABRT KILL TERM INT
-
-    # The mtab file should already be available in the image.
-    # This following instruction will be deleted
-    [ ! -e ${JUNEST_HOME}/etc/mtab ] && ln_cmd -s /proc/self/mounts ${JUNEST_HOME}/etc/mtab
+    trap "[ -z $uid ] || chown_cmd -R ${uid} ${JUNEST_HOME};" EXIT QUIT ABRT KILL TERM INT
 
     JUNEST_ENV=1 chroot_cmd "$JUNEST_HOME" "${SH[@]}" "-c" "${main_cmd}"
 }
@@ -268,36 +316,89 @@ function _run_env_with_qemu(){
     _run_env_with_proot "$proot_args" "${@}"
 }
 
+#######################################
+# Run JuNest as fakeroot.
+#
+# Globals:
+#   JUNEST_HOME (RO)         : The JuNest home directory.
+#   EUID (RO)                : The user ID.
+#   SH (RO)                  : Contains the default command to run in JuNest.
+# Arguments:
+#   cmd ($@?)                : The command to run inside JuNest environment.
+#                              Default command is defined by SH variable.
+# Returns:
+#   $ROOT_ACCESS_ERROR       : If the user is the real root.
+# Output:
+#   -                        : The command output.
+#######################################
 function run_env_as_fakeroot(){
     (( EUID == 0 )) && \
-        die "You cannot access with root privileges. Use --root option instead."
-    # The mtab file should already be available in the image.
-    # This following instruction will be deleted
-    [ ! -e ${JUNEST_HOME}/etc/mtab ] && ln_cmd -s /proc/self/mounts ${JUNEST_HOME}/etc/mtab
+        die_on_status $ROOT_ACCESS_ERROR "You cannot access with root privileges. Use --root option instead."
+
     _run_env_with_qemu "-S ${JUNEST_HOME} $1" "${@:2}"
 }
 
+#######################################
+# Run JuNest as normal user.
+#
+# Globals:
+#   JUNEST_HOME (RO)         : The JuNest home directory.
+#   EUID (RO)                : The user ID.
+#   SH (RO)                  : Contains the default command to run in JuNest.
+# Arguments:
+#   cmd ($@?)                : The command to run inside JuNest environment.
+#                              Default command is defined by SH variable.
+# Returns:
+#   $ROOT_ACCESS_ERROR       : If the user is the real root.
+# Output:
+#   -                        : The command output.
+#######################################
 function run_env_as_user(){
     (( EUID == 0 )) && \
-        die "You cannot access with root privileges. Use --root option instead."
-    # The mtab file should already be available in the image.
-    # This following instruction will be deleted
-    [ ! -e ${JUNEST_HOME}/etc/mtab ] && ln_cmd -s /proc/self/mounts ${JUNEST_HOME}/etc/mtab
-    _run_env_with_qemu "$(_provide_bindings_as_user) -r ${JUNEST_HOME} $1" "${@:2}"
+        die_on_status $ROOT_ACCESS_ERROR "You cannot access with root privileges. Use --root option instead."
+
+    _provide_bindings_as_user
+    local bindings="$RESULT"
+    unset RESULT
+    _run_env_with_qemu "$bindings -r ${JUNEST_HOME} $1" "${@:2}"
 }
 
+#######################################
+# Provide the proot binding options for the normal user.
+#
+# Globals:
+#   HOME (RO)       : The home directory.
+#   RESULT (WO)     : Contains the binding options.
+# Arguments:
+#   None
+# Returns:
+#   None
+# Output:
+#   None
+#######################################
 function _provide_bindings_as_user(){
     # The list of bindings can be found in `proot --help`. This function excludes
     # /etc/mtab file so that it will not give conflicts with the related
     # symlink in the image.
-    local existing_bindings=""
+    RESULT=""
     for bind in "/etc/host.conf" "/etc/hosts" "/etc/hosts.equiv" "/etc/netgroup" "/etc/networks" "/etc/passwd" "/etc/group" "/etc/nsswitch.conf" "/etc/resolv.conf" "/etc/localtime" "/dev" "/sys" "/proc" "/tmp" "$HOME"
     do
-        [ -e "$bind" ] && existing_bindings="-b $bind $existing_bindings"
+        [ -e "$bind" ] && RESULT="-b $bind $RESULT"
     done
-    echo $existing_bindings
 }
 
+#######################################
+# Remove an existing JuNest system.
+#
+# Globals:
+#  JUNEST_HOME (RO)         : The JuNest home directory to remove.
+# Arguments:
+#  None
+# Returns:
+#  None
+# Output:
+#  None
+#######################################
 function delete_env(){
     ! ask "Are you sure to delete ${NAME} located in ${JUNEST_HOME}" "N" && return
     if mountpoint -q ${JUNEST_HOME}
@@ -364,6 +465,7 @@ function build_image_env(){
     # yaourt requires sed
     sudo pacstrap -G -M -d ${maindir}/root pacman coreutils libunistring archlinux-keyring sed
     sudo bash -c "echo 'Server = $DEFAULT_MIRROR' >> ${maindir}/root/etc/pacman.d/mirrorlist"
+    mkdir -p ${maindir}/root/run/lock
 
     info "Install ${NAME} script..."
     sudo pacman --noconfirm --root ${maindir}/root -S git
diff --git a/lib/util.sh b/lib/util.sh
deleted file mode 100644
index 6865c16..0000000
--- a/lib/util.sh
+++ /dev/null
@@ -1,93 +0,0 @@
-#!/usr/bin/env bash
-#
-# This file is part of JuNest (https://github.com/fsquillace/junest)
-#
-# Copyright (c) 2015
-#
-# This program is free software; you can redistribute it and/or modify it
-# under the terms of the GNU Library General Public License as published
-# by the Free Software Foundation; either version 2, or (at your option)
-# any later version.
-#
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with this program.  If not, see <http://www.gnu.org/licenses/>.
-
-function echoerr(){
-    echo "$@" 1>&2
-}
-function die(){
-# $@: msg (mandatory) - str: Message to print
-    error $@
-    exit 1
-}
-function error(){
-# $@: msg (mandatory) - str: Message to print
-    echoerr -e "\033[1;31m$@\033[0m"
-}
-function warn(){
-# $@: msg (mandatory) - str: Message to print
-    echoerr -e "\033[1;33m$@\033[0m"
-}
-function info(){
-# $@: msg (mandatory) - str: Message to print
-    echo -e "\033[1;37m$@\033[0m"
-}
-
-function ask(){
-    # $1: question string
-    # $2: default value - can be either Y, y, N, n (by default Y)
-
-    local default="Y"
-    [ -z $2 ] || default=$(echo "$2" | tr '[:lower:]' '[:upper:]')
-
-    local other="n"
-    [ "$default" == "N" ] && other="y"
-
-    local prompt="$1 (${default}/${other})> "
-
-    local res="none"
-    while [ "$res" != "Y" ] && [ "$res" != "N"  ] && [ "$res" != "" ];
-    do
-        read -p "$prompt" res
-        res=$(echo "$res" | tr '[:lower:]' '[:upper:]')
-    done
-
-    [ "$res" == "" ] && res="$default"
-
-    if [ "$res" == "Y" ]
-    then
-        return 0
-    else
-        return 1
-    fi
-
-}
-
-function insert_quotes_on_spaces(){
-# It inserts quotes between arguments.
-# Useful to preserve quotes on command
-# to be used inside sh -c/bash -c
-    C=''
-    whitespace="[[:space:]]"
-    for i in "$@"
-    do
-        if [[ $i =~ $whitespace ]]
-        then
-            C="$C \"$i\""
-        else
-            C="$C $i"
-        fi
-    done
-    echo $C
-}
-
-contains_element () {
-  local e
-  for e in "${@:2}"; do [[ "$e" == "$1" ]] && return 0; done
-  return 1
-}
diff --git a/lib/utils.sh b/lib/utils.sh
new file mode 100644
index 0000000..840fbe9
--- /dev/null
+++ b/lib/utils.sh
@@ -0,0 +1,195 @@
+#!/usr/bin/env bash
+
+NULL_EXCEPTION=11
+WRONG_ANSWER=33
+
+#######################################
+# Check if the argument is null.
+#
+# Globals:
+#   None
+# Arguments:
+#   argument ($1)    : Argument to check.
+# Returns:
+#   0                : If argument is not null.
+#   NULL_EXCEPTION   : If argument is null.
+# Output:
+#   None
+#######################################
+function check_not_null() {
+    [ -z "$1" ] && { error "Error: null argument $1"; return $NULL_EXCEPTION; }
+    return 0
+}
+
+#######################################
+# Redirect message to stderr.
+#
+# Globals:
+#   None
+# Arguments:
+#   msg ($@): Message to print.
+# Returns:
+#   None
+# Output:
+#   Message printed to stderr.
+#######################################
+function echoerr() {
+    echo "$@" 1>&2;
+}
+
+#######################################
+# Print an error message to stderr and exit program.
+#
+# Globals:
+#   None
+# Arguments:
+#   msg ($@)   : Message to print.
+# Returns:
+#   1          : The unique exit status printed.
+# Output:
+#   Message printed to stderr.
+#######################################
+function die() {
+    error $@
+    exit 1
+}
+
+#######################################
+# Print an error message to stderr and exit program with a given status.
+#
+# Globals:
+#   None
+# Arguments:
+#   status ($1)     : The exit status to use.
+#   msg ($2-)       : Message to print.
+# Returns:
+#   $?              : The $status exit status.
+# Output:
+#   Message printed to stderr.
+#######################################
+function die_on_status() {
+    status=$1
+    shift
+    error $@
+    exit $status
+}
+
+#######################################
+# Print an error message to stderr.
+#
+# Globals:
+#   None
+# Arguments:
+#   msg ($@): Message to print.
+# Returns:
+#   None
+# Output:
+#   Message printed to stderr.
+#######################################
+function error() {
+    echoerr -e "\033[1;31m$@\033[0m"
+}
+
+#######################################
+# Print a warn message to stderr.
+#
+# Globals:
+#   None
+# Arguments:
+#   msg ($@): Message to print.
+# Returns:
+#   None
+# Output:
+#   Message printed to stderr.
+#######################################
+function warn() {
+    # $@: msg (mandatory) - str: Message to print
+    echoerr -e "\033[1;33m$@\033[0m"
+}
+
+#######################################
+# Print an info message to stdout.
+#
+# Globals:
+#   None
+# Arguments:
+#   msg ($@): Message to print.
+# Returns:
+#   None
+# Output:
+#   Message printed to stdout.
+#######################################
+function info(){
+    echo -e "\033[1;36m$@\033[0m"
+}
+
+#######################################
+# Ask a question and wait to receive an answer from stdin.
+# It returns $default_answer if no answer has be received from stdin.
+#
+# Globals:
+#   None
+# Arguments:
+#   question ($1)       : The question to ask.
+#   default_answer ($2) : Possible values: 'Y', 'y', 'N', 'n' (default: 'Y')
+# Returns:
+#   0                   : If user replied with either 'Y' or 'y'.
+#   1                   : If user replied with either 'N' or 'n'.
+#   WRONG_ANSWER        : If `default_answer` is not one of the possible values.
+# Output:
+#   Print the question to ask.
+#######################################
+function ask(){
+    local question=$1
+    local default_answer=$2
+    check_not_null $question
+
+    if [ ! -z "$default_answer" ]
+    then
+        local answers="Y y N n"
+        [[ "$answers" =~ "$default_answer" ]] || { error "The default answer: $default_answer is wrong."; return $WRONG_ANSWER; }
+    fi
+
+    local default="Y"
+    [ -z "$default_answer" ] || default=$(echo "$default_answer" | tr '[:lower:]' '[:upper:]')
+
+    local other="n"
+    [ "$default" == "N" ] && other="y"
+
+    local prompt=$(info "$question (${default}/${other})> ")
+
+    local res="none"
+    while [ "$res" != "Y" ] && [ "$res" != "N"  ] && [ "$res" != "" ];
+    do
+        read -p "$prompt" res
+        res=$(echo "$res" | tr '[:lower:]' '[:upper:]')
+    done
+
+    [ "$res" == "" ] && res="$default"
+
+    [ "$res" == "Y" ]
+}
+
+function insert_quotes_on_spaces(){
+# It inserts quotes between arguments.
+# Useful to preserve quotes on command
+# to be used inside sh -c/bash -c
+    C=''
+    whitespace="[[:space:]]"
+    for i in "$@"
+    do
+        if [[ $i =~ $whitespace ]]
+        then
+            C="$C \"$i\""
+        else
+            C="$C $i"
+        fi
+    done
+    echo $C
+}
+
+contains_element () {
+  local e
+  for e in "${@:2}"; do [[ "$e" == "$1" ]] && return 0; done
+  return 1
+}
diff --git a/tests/integ-tests/install-bash.sh b/tests/integ-tests/install-bash.sh
new file mode 100755
index 0000000..575c9c5
--- /dev/null
+++ b/tests/integ-tests/install-bash.sh
@@ -0,0 +1,13 @@
+#!/bin/sh
+set -ex
+
+VERSION=$1
+
+cd /tmp
+wget http://ftp.gnu.org/gnu/bash/bash-$VERSION.tar.gz
+
+tar -zxf bash-$VERSION.tar.gz
+cd /tmp/bash-$VERSION*
+./configure
+make
+sudo make install
diff --git a/tests/test-cli.sh b/tests/test-cli.sh
deleted file mode 100755
index 46d38d1..0000000
--- a/tests/test-cli.sh
+++ /dev/null
@@ -1,202 +0,0 @@
-#!/bin/bash
-source $(dirname $0)/../bin/junest -h &> /dev/null
-
-# Disable the exiterr
-set +e
-
-function setUp(){
-    function is_env_installed(){
-        return 0
-    }
-}
-
-## Mock functions ##
-function usage(){
-    echo "usage"
-}
-function version(){
-    echo "version"
-}
-function build_image_env(){
-    local disable_validation=$1
-    local skip_root_tests=$2
-    echo "build_image_env($disable_validation,$skip_root_tests)"
-}
-function check_env(){
-    local env_home=$1
-    local cmd_script=$2
-    local skip_root_tests=$3
-    echo "check_env($env_home,$cmd_script,$skip_root_tests)"
-}
-function delete_env(){
-    echo "delete_env"
-}
-function setup_env_from_file(){
-    echo "setup_env_from_file($1)"
-}
-function setup_env(){
-    echo "setup_env($1)"
-}
-function run_env_as_fakeroot(){
-    local proot_args="$1"
-    shift
-    echo "run_env_as_fakeroot($proot_args,$@)"
-}
-function run_env_as_root(){
-    echo "run_env_as_root $@"
-}
-function run_env_as_user(){
-    local proot_args="$1"
-    shift
-    echo "run_env_as_user($proot_args,$@)"
-}
-
-function wrap_env(){
-    parse_arguments "$@"
-    check_cli
-    execute_operation
-}
-
-function test_help(){
-    local output=$(wrap_env -h)
-    assertEquals $output "usage"
-    local output=$(wrap_env --help)
-    assertEquals $output "usage"
-}
-function test_version(){
-    local output=$(wrap_env -v)
-    assertEquals $output "version"
-    local output=$(wrap_env --version)
-    assertEquals $output "version"
-}
-function test_build_image_env(){
-    local output=$(wrap_env -b)
-    assertEquals $output "build_image_env(false,false)"
-    local output=$(wrap_env --build-image)
-    assertEquals $output "build_image_env(false,false)"
-    local output=$(wrap_env -b -s)
-    assertEquals $output "build_image_env(false,true)"
-    local output=$(wrap_env -b -n)
-    assertEquals $output "build_image_env(true,false)"
-    local output=$(wrap_env -b -n -s)
-    assertEquals $output "build_image_env(true,true)"
-    local output=$(wrap_env --build-image --disable-validation --skip-root-tests)
-    assertEquals $output "build_image_env(true,true)"
-}
-function test_check_env(){
-    local output=$(wrap_env -c myscript)
-    assertEquals $output "check_env(${JUNEST_HOME},myscript,false)"
-    local output=$(wrap_env --check myscript)
-    assertEquals $output "check_env(${JUNEST_HOME},myscript,false)"
-    local output=$(wrap_env -c myscript -s)
-    assertEquals $output "check_env(${JUNEST_HOME},myscript,true)"
-    local output=$(wrap_env --check myscript --skip-root-tests)
-    assertEquals $output "check_env(${JUNEST_HOME},myscript,true)"
-}
-function test_delete_env(){
-    local output=$(wrap_env -d)
-    assertEquals $output "delete_env"
-    local output=$(wrap_env --delete)
-    assertEquals $output "delete_env"
-}
-#function test_setup_env_from_file(){
-    #local output=$(wrap_env -i myimage)
-    #assertEquals $output "setup_env_from_file(myimage)"
-    #local output=$(wrap_env --setup-from-file myimage)
-    #assertEquals $output "setup_env_from_file(myimage)"
-#}
-function test_setup_env_from_file(){
-    is_env_installed(){
-        return 1
-    }
-    local output=$(wrap_env -i myimage)
-    assertEquals "$output" "$(echo -e "setup_env_from_file(myimage)\nrun_env_as_user(,)")"
-    local output=$(wrap_env --setup-from-file myimage)
-    assertEquals "$output" "$(echo -e "setup_env_from_file(myimage)\nrun_env_as_user(,)")"
-
-    is_env_installed(){
-        return 0
-    }
-    $(wrap_env -i myimage 2> /dev/null)
-    assertEquals 1 $?
-}
-
-function test_setup_env(){
-    is_env_installed(){
-        return 1
-    }
-    local output=$(wrap_env -a arm)
-    assertEquals "$output" "$(echo -e "setup_env(arm)\nrun_env_as_user(,)")"
-    local output=$(wrap_env --arch arm)
-    assertEquals "$output" "$(echo -e "setup_env(arm)\nrun_env_as_user(,)")"
-    local output=$(wrap_env)
-    assertEquals "$output" "$(echo -e "setup_env()\nrun_env_as_user(,)")"
-
-    is_env_installed(){
-        return 0
-    }
-    $(wrap_env -a arm 2> /dev/null)
-    assertEquals 1 $?
-}
-function test_run_env_as_fakeroot(){
-    local output=$(wrap_env -f)
-    assertEquals $output "run_env_as_fakeroot(,)"
-    local output=$(wrap_env --fakeroot)
-    assertEquals $output "run_env_as_fakeroot(,)"
-
-    local output=$(wrap_env -f -p "-b arg")
-    assertEquals "${output[@]}" "run_env_as_fakeroot(-b arg,)"
-    local output=$(wrap_env -f -p "-b arg" -- command -kv)
-    assertEquals "${output[@]}" "run_env_as_fakeroot(-b arg,command -kv)"
-    local output=$(wrap_env -f command --as)
-    assertEquals "${output[@]}" "run_env_as_fakeroot(,command --as)"
-    $(wrap_env -a "myarch" -f command --as 2> /dev/null)
-    assertEquals 1 $?
-}
-function test_run_env_as_user(){
-    local output=$(wrap_env)
-    assertEquals $output "run_env_as_user(,)"
-
-    local output=$(wrap_env -p "-b arg")
-    assertEquals "$output" "run_env_as_user(-b arg,)"
-    local output=$(wrap_env -p "-b arg" -- command -ll)
-    assertEquals "$output" "run_env_as_user(-b arg,command -ll)"
-    local output=$(wrap_env command -ls)
-    assertEquals "$output" "run_env_as_user(,command -ls)"
-    $(wrap_env -a "myarch" -- command -ls 2> /dev/null)
-    assertEquals 1 $?
-}
-function test_run_env_as_root(){
-    local output=$(wrap_env -r)
-    assertEquals $output "run_env_as_root"
-
-    local output=$(wrap_env -r command)
-    assertEquals "${output[@]}" "run_env_as_root command"
-}
-
-function test_check_cli(){
-    $(wrap_env -b -h 2> /dev/null)
-    assertEquals $? 1
-    $(wrap_env -b -c 2> /dev/null)
-    assertEquals $? 1
-    $(wrap_env -d -s 2> /dev/null)
-    assertEquals $? 1
-    $(wrap_env -n -v 2> /dev/null)
-    assertEquals $? 1
-    $(wrap_env -d -r 2> /dev/null)
-    assertEquals $? 1
-    $(wrap_env -h -f 2> /dev/null)
-    assertEquals $? 1
-    $(wrap_env -v -i fsd 2> /dev/null)
-    assertEquals $? 1
-    $(wrap_env -f -r 2> /dev/null)
-    assertEquals $? 1
-    $(wrap_env -p args -v 2> /dev/null)
-    assertEquals $? 1
-    $(wrap_env -a arch -v 2> /dev/null)
-    assertEquals $? 1
-    $(wrap_env -d args 2> /dev/null)
-    assertEquals $? 1
-}
-
-source $(dirname $0)/shunit2
diff --git a/tests/test-core.sh b/tests/test-core.sh
deleted file mode 100755
index bd57032..0000000
--- a/tests/test-core.sh
+++ /dev/null
@@ -1,362 +0,0 @@
-#!/bin/bash
-
-function oneTimeSetUp(){
-    [ -z "$SKIP_ROOT_TESTS" ] && SKIP_ROOT_TESTS=0
-
-    CURRPWD=$PWD
-    ENV_MAIN_HOME=/tmp/envtesthome
-    [ -e $ENV_MAIN_HOME ] || JUNEST_HOME=$ENV_MAIN_HOME bash --rcfile "$(dirname $0)/../lib/core.sh" -ic "setup_env"
-    JUNEST_HOME=""
-}
-
-function install_mini_env(){
-    cp -rfa $ENV_MAIN_HOME/* $JUNEST_HOME
-}
-
-function setUp(){
-    cd $CURRPWD
-    JUNEST_HOME=$(TMPDIR=/tmp mktemp -d -t envhome.XXXXXXXXXX)
-    JUNEST_BASE="$CURRPWD/$(dirname $0)/.."
-    source "${JUNEST_BASE}/lib/core.sh"
-    ORIGIN_WD=$(TMPDIR=/tmp mktemp -d -t envowd.XXXXXXXXXX)
-    cd $ORIGIN_WD
-    JUNEST_TEMPDIR=$(TMPDIR=/tmp mktemp -d -t envtemp.XXXXXXXXXX)
-
-    set +e
-
-    trap - QUIT EXIT ABRT KILL TERM INT
-    trap "rm -rf ${JUNEST_HOME}; rm -rf ${ORIGIN_WD}; rm -rf ${JUNEST_TEMPDIR}" EXIT QUIT ABRT KILL TERM INT
-}
-
-
-function tearDown(){
-    # the CA directories are read only and can be deleted only by changing the mod
-    [ -d ${JUNEST_HOME}/etc/ca-certificates ] && chmod -R +w ${JUNEST_HOME}/etc/ca-certificates
-    rm -rf $JUNEST_HOME
-    rm -rf $ORIGIN_WD
-    rm -rf $JUNEST_TEMPDIR
-    trap - QUIT EXIT ABRT KILL TERM INT
-}
-
-
-function test_is_env_installed(){
-    is_env_installed
-    assertEquals $? 1
-    touch $JUNEST_HOME/just_file
-    is_env_installed
-    assertEquals $? 0
-}
-
-
-function test_download(){
-    WGET=/bin/true
-    CURL=/bin/false
-    download_cmd
-    assertEquals $? 0
-
-    WGET=/bin/false
-    CURL=/bin/true
-    download_cmd
-    assertEquals $? 0
-
-    $(WGET=/bin/false CURL=/bin/false download_cmd something 2> /dev/null)
-    assertEquals $? 1
-}
-
-function test_ln(){
-    install_mini_env
-
-    touch ln_file
-    ln_cmd -s ln_file new_file
-    assertEquals $? 0
-    assertTrue "[ -e new_file ]"
-    rm new_file
-
-    touch ln_file
-    OLDPATH="$PATH"
-    PATH=""
-    ln_cmd -s ln_file new_file 2> /dev/null
-    local ret=$?
-    PATH="$OLDPATH"
-    assertEquals $ret 0
-    assertTrue "[ -e new_file ]"
-}
-
-function test_rm(){
-    install_mini_env
-
-    touch rm_file
-    rm_cmd rm_file
-    assertEquals $? 0
-    assertTrue "[ ! -e rm_file ]"
-
-    touch rm_file
-    OLDPATH="$PATH"
-    PATH=""
-    rm_cmd rm_file 2> /dev/null
-    local ret=$?
-    PATH="$OLDPATH"
-    assertEquals $ret 0
-    assertTrue "[ ! -e rm_file ]"
-}
-
-function test_chown(){
-    install_mini_env
-
-    local id=$(id -u)
-
-    touch chown_file
-    chown_cmd $id chown_file
-    assertEquals $? 0
-
-    touch chown_file
-    OLDPATH="$PATH"
-    PATH=""
-    chown_cmd $id chown_file 2> /dev/null
-    local ret=$?
-    PATH="$OLDPATH"
-    assertEquals $ret 0
-}
-
-function test_mkdir(){
-    install_mini_env
-
-    mkdir_cmd -p new_dir/new_dir
-    assertEquals $? 0
-    assertTrue "[ -d new_dir/new_dir ]"
-    rm -rf new_dir
-
-    OLDPATH="$PATH"
-    PATH=""
-    mkdir_cmd -p new_dir/new_dir 2> /dev/null
-    local ret=$?
-    PATH="$OLDPATH"
-    assertEquals $ret 0
-    assertTrue "[ -d new_dir/new_dir ]"
-}
-
-function test_setup_env(){
-    wget_mock(){
-        # Proof that the setup is happening
-        # inside $JUNEST_TEMPDIR
-        local cwd=${PWD#${JUNEST_TEMPDIR}}
-        local parent_dir=${PWD%${cwd}}
-        assertEquals "$JUNEST_TEMPDIR" "${parent_dir}"
-        touch file
-        tar -czvf ${CMD}-${ARCH}.tar.gz file
-    }
-    WGET=wget_mock
-    setup_env 1> /dev/null
-    assertTrue "[ -e $JUNEST_HOME/file ]"
-    assertTrue "[ -e $JUNEST_HOME/run/lock ]"
-
-    $(setup_env "noarch" 2> /dev/null)
-    assertEquals 1 $?
-}
-
-
-function test_setup_env_from_file(){
-    touch file
-    tar -czvf ${CMD}-${ARCH}.tar.gz file 1> /dev/null
-    setup_env_from_file ${CMD}-${ARCH}.tar.gz &> /dev/null
-    assertTrue "[ -e $JUNEST_HOME/file ]"
-    assertTrue "[ -e $JUNEST_HOME/run/lock ]"
-
-    $(setup_env_from_file noexist.tar.gz 2> /dev/null)
-    assertEquals $? 1
-}
-
-function test_setup_env_from_file_with_absolute_path(){
-    touch file
-    tar -czvf ${CMD}-${ARCH}.tar.gz file 1> /dev/null
-    setup_env_from_file ${ORIGIN_WD}/${CMD}-${ARCH}.tar.gz &> /dev/null
-    assertTrue "[ -e $JUNEST_HOME/file ]"
-    assertTrue "[ -e $JUNEST_HOME/run/lock ]"
-}
-
-function test_run_env_as_root(){
-    [ $SKIP_ROOT_TESTS -eq 1 ] && return
-
-    install_mini_env
-    CHROOT="sudo $CHROOT"
-    CLASSIC_CHROOT="sudo $CLASSIC_CHROOT"
-    CHOWN="sudo $CHOWN"
-
-    local output=$(run_env_as_root pwd)
-    assertEquals "/" "$output"
-    run_env_as_root [ -e /run/lock ]
-    assertEquals 0 $?
-    run_env_as_root [ -e $HOME ]
-    assertEquals 0 $?
-
-    # test that normal user has ownership of the files created by root
-    run_env_as_root touch /a_root_file
-    # This ensure that the trap will be executed
-    kill -TERM $$
-    local output=$(run_env_as_root stat -c '%u' /a_root_file)
-    assertEquals "$UID" "$output"
-
-    SH=("sh" "--login" "-c" "type -t type")
-    local output=$(run_env_as_root)
-    assertEquals "builtin" "$output"
-    SH=("sh" "--login" "-c" "[ -e /run/lock ]")
-    run_env_as_root
-    assertEquals 0 $?
-    SH=("sh" "--login" "-c" "[ -e $HOME ]")
-    run_env_as_root
-    assertEquals 0 $?
-}
-
-function test_run_env_as_root_different_arch(){
-    [ $SKIP_ROOT_TESTS -eq 1 ] && return
-
-    install_mini_env
-    echo "JUNEST_ARCH=XXX" > ${JUNEST_HOME}/etc/junest/info
-    $(run_env_as_root pwd 2> /dev/null)
-    assertEquals 1 $?
-}
-
-function test_run_env_as_classic_root(){
-    [ $SKIP_ROOT_TESTS -eq 1 ] && return
-
-    install_mini_env
-    CHROOT="sudo unknowncommand"
-    CLASSIC_CHROOT="sudo $CLASSIC_CHROOT"
-    CHOWN="sudo $CHOWN"
-
-    local output=$(run_env_as_root pwd 2> /dev/null)
-    assertEquals "/" "$output"
-    run_env_as_root [ -e /run/lock ] 2> /dev/null
-    assertEquals 0 $?
-}
-
-function test_run_env_as_junest_root(){
-    [ $SKIP_ROOT_TESTS -eq 1 ] && return
-
-    install_mini_env
-    CHROOT="sudo unknowncommand"
-    CLASSIC_CHROOT="sudo unknowncommand"
-    LD_EXEC="sudo $LD_EXEC"
-    CHOWN="sudo $CHOWN"
-
-    local output=$(run_env_as_root pwd 2> /dev/null)
-    assertEquals "/" "$output"
-    run_env_as_root [ -e /run/lock ] 2> /dev/null
-    assertEquals 0 $?
-    run_env_as_root [ -e $HOME ] 2> /dev/null
-    assertEquals 1 $?
-}
-
-function test_run_env_as_user(){
-    install_mini_env
-    local output=$(run_env_as_user "-k 3.10" "/usr/bin/mkdir" "-v" "/newdir2" | awk -F: '{print $1}')
-    assertEquals "$output" "/usr/bin/mkdir"
-    assertTrue "[ -e $JUNEST_HOME/newdir2 ]"
-
-    SH=("/usr/bin/echo")
-    local output=$(run_env_as_user "-k 3.10")
-    assertEquals "-c :" "$output"
-}
-
-function test_run_env_as_proot_mtab(){
-    install_mini_env
-    $(run_env_as_fakeroot "-k 3.10" "echo")
-    assertTrue "[ -e $JUNEST_HOME/etc/mtab ]"
-    $(run_env_as_user "-k 3.10" "echo")
-    assertTrue "[ -e $JUNEST_HOME/etc/mtab ]"
-}
-
-function test_run_env_as_root_mtab(){
-    [ $SKIP_ROOT_TESTS -eq 1 ] && return
-
-    install_mini_env
-    CHROOT="sudo $CHROOT"
-    CLASSIC_CHROOT="sudo $CLASSIC_CHROOT"
-    CHOWN="sudo $CHOWN"
-    $(run_env_as_root "echo")
-    assertTrue "[ ! -e $JUNEST_HOME/etc/mtab ]"
-}
-
-function test_run_env_with_quotes(){
-    install_mini_env
-    local output=$(run_env_as_user "-k 3.10" "bash" "-c" "/usr/bin/mkdir -v /newdir2" | awk -F: '{print $1}')
-    assertEquals "/usr/bin/mkdir" "$output"
-    assertTrue "[ -e $JUNEST_HOME/newdir2 ]"
-}
-
-function test_run_env_as_user_proot_args(){
-    install_mini_env
-    run_env_as_user "--help" "" &> /dev/null
-    assertEquals 0 $?
-
-    mkdir $JUNEST_TEMPDIR/newdir
-    touch $JUNEST_TEMPDIR/newdir/newfile
-    run_env_as_user "-b $JUNEST_TEMPDIR/newdir:/newdir -k 3.10" "ls" "-l" "/newdir/newfile" &> /dev/null
-    assertEquals 0 $?
-
-    $(_run_env_with_proot --helps 2> /dev/null)
-    assertEquals 1 $?
-}
-
-function test_run_env_with_proot_compat(){
-    PROOT="/bin/true"
-    _run_env_with_proot "" "" &> /dev/null
-    assertEquals 0 $?
-
-    $(PROOT="/bin/false" _run_env_with_proot --helps 2> /dev/null)
-    assertEquals 1 $?
-}
-
-function test_run_env_with_proot_as_root(){
-    [ $SKIP_ROOT_TESTS -eq 1 ] && return
-
-    install_mini_env
-
-    $(sudo run_env_as_user 2> /dev/null)
-    assertEquals 1 $?
-    $(sudo run_env_as_fakeroot 2> /dev/null)
-    assertEquals 1 $?
-}
-
-function test_run_proot_seccomp(){
-    envv(){
-        env
-    }
-    PROOT=envv
-    local output=$(proot_cmd | grep "^PROOT_NO_SECCOMP")
-    assertEquals "" "$output"
-
-    envv(){
-        env | grep "^PROOT_NO_SECCOMP"
-    }
-    PROOT=envv
-    local output=$(proot_cmd | grep "^PROOT_NO_SECCOMP")
-    # The variable PROOT_NO_SECCOMP will be produced
-    # twice due to the fallback mechanism
-    assertEquals "PROOT_NO_SECCOMP=1
-PROOT_NO_SECCOMP=1" "$output"
-}
-
-function test_run_env_as_fakeroot(){
-    install_mini_env
-    local output=$(run_env_as_fakeroot "-k 3.10" "id" | awk '{print $1}')
-    assertEquals "uid=0(root)" "$output"
-}
-
-function test_delete_env(){
-    install_mini_env
-    echo "N" | delete_env 1> /dev/null
-    is_env_installed
-    assertEquals 0 $?
-    echo "Y" | delete_env 1> /dev/null
-    is_env_installed
-    assertEquals 1 $?
-}
-
-function test_nested_env(){
-    install_mini_env
-    JUNEST_ENV=1 bash -ic "source $CURRPWD/$(dirname $0)/../lib/core.sh" &> /dev/null
-    assertEquals 1 $?
-}
-
-source $(dirname $0)/shunit2
diff --git a/tests/test-util.sh b/tests/test-util.sh
deleted file mode 100755
index 80fd660..0000000
--- a/tests/test-util.sh
+++ /dev/null
@@ -1,72 +0,0 @@
-#!/bin/bash
-source "$(dirname $0)/../lib/util.sh"
-
-# Disable the exiterr
-set +e
-
-function test_echoerr(){
-    local actual=$(echoerr "Test" 2>&1)
-    assertEquals "$actual" "Test"
-}
-
-function test_error(){
-    local actual=$(error "Test" 2>&1)
-    local expected=$(echo -e "\033[1;31mTest\033[0m")
-    assertEquals "$actual" "$expected"
-}
-
-function test_warn(){
-    local actual=$(warn "Test" 2>&1)
-    local expected=$(echo -e "\033[1;33mTest\033[0m")
-    assertEquals "$actual" "$expected"
-}
-
-function test_info(){
-    local actual=$(info "Test")
-    local expected=$(echo -e "\033[1;37mTest\033[0m")
-    assertEquals "$actual" "$expected"
-}
-
-function test_die(){
-    local actual=$(die "Test" 2>&1)
-    local expected=$(echo -e "\033[1;31mTest\033[0m")
-    assertEquals "$actual" "$expected"
-    $(die Dying 2> /dev/null)
-    assertEquals $? 1
-}
-
-function test_ask(){
-    echo "Y" | ask "Test" &> /dev/null
-    assertEquals $? 0
-    echo "y" | ask "Test" &> /dev/null
-    assertEquals $? 0
-    echo "N" | ask "Test" &> /dev/null
-    assertEquals $? 1
-    echo "n" | ask "Test" &> /dev/null
-    assertEquals $? 1
-    echo -e "\n" | ask "Test" &> /dev/null
-    assertEquals $? 0
-    echo -e "\n" | ask "Test" "N" &> /dev/null
-    assertEquals $? 1
-    echo -e "asdf\n\n" | ask "Test" "N" &> /dev/null
-    assertEquals $? 1
-}
-
-function test_insert_quotes_on_spaces(){
-    local actual=$(insert_quotes_on_spaces this is "a test")
-    assertEquals "this is \"a test\"" "$actual"
-
-    local actual=$(insert_quotes_on_spaces this is 'a test')
-    assertEquals "this is \"a test\"" "$actual"
-}
-
-function test_contains_element(){
-    array=("something to search for" "a string" "test2000")
-    contains_element "a string" "${array[@]}"
-    assertEquals "$?" "0"
-
-    contains_element "blabla" "${array[@]}"
-    assertEquals "$?" "1"
-}
-
-source $(dirname $0)/shunit2
diff --git a/tests/shunit2 b/tests/unit-tests/shunit2
similarity index 100%
rename from tests/shunit2
rename to tests/unit-tests/shunit2
diff --git a/tests/unit-tests/test-cli.sh b/tests/unit-tests/test-cli.sh
new file mode 100755
index 0000000..5dd2513
--- /dev/null
+++ b/tests/unit-tests/test-cli.sh
@@ -0,0 +1,181 @@
+#!/bin/bash
+source "$(dirname $0)/utils.sh"
+
+source $(dirname $0)/../../bin/junest -h &> /dev/null
+
+# Disable the exiterr
+set +e
+
+function oneTimeSetUp(){
+    setUpUnitTests
+}
+
+function setUp(){
+    function is_env_installed(){
+        return 0
+    }
+}
+
+## Mock functions ##
+function usage(){
+    echo "usage"
+}
+function version(){
+    echo "version"
+}
+function build_image_env(){
+    local disable_validation=$1
+    local skip_root_tests=$2
+    echo "build_image_env($disable_validation,$skip_root_tests)"
+}
+function check_env(){
+    local env_home=$1
+    local cmd_script=$2
+    local skip_root_tests=$3
+    echo "check_env($env_home,$cmd_script,$skip_root_tests)"
+}
+function delete_env(){
+    echo "delete_env"
+}
+function setup_env_from_file(){
+    echo "setup_env_from_file($1)"
+}
+function setup_env(){
+    echo "setup_env($1)"
+}
+function run_env_as_fakeroot(){
+    local proot_args="$1"
+    shift
+    echo "run_env_as_fakeroot($proot_args,$@)"
+}
+function run_env_as_root(){
+    echo "run_env_as_root $@"
+}
+function run_env_as_user(){
+    local proot_args="$1"
+    shift
+    echo "run_env_as_user($proot_args,$@)"
+}
+
+function test_help(){
+    assertCommandSuccess cli -h
+    assertEquals "usage" "$(cat $STDOUTF)"
+    assertCommandSuccess cli --help
+    assertEquals "usage" "$(cat $STDOUTF)"
+}
+function test_version(){
+    assertCommandSuccess cli -v
+    assertEquals "version" "$(cat $STDOUTF)"
+    assertCommandSuccess cli --version
+    assertEquals "version" "$(cat $STDOUTF)"
+}
+function test_build_image_env(){
+    assertCommandSuccess cli -b
+    assertEquals "build_image_env(false,false)" "$(cat $STDOUTF)"
+    assertCommandSuccess cli --build-image
+    assertEquals "build_image_env(false,false)" "$(cat $STDOUTF)"
+    assertCommandSuccess cli -b -s
+    assertEquals "build_image_env(false,true)" "$(cat $STDOUTF)"
+    assertCommandSuccess cli -b -n
+    assertEquals "build_image_env(true,false)" "$(cat $STDOUTF)"
+    assertCommandSuccess cli -b -n -s
+    assertEquals "build_image_env(true,true)" "$(cat $STDOUTF)"
+    assertCommandSuccess cli --build-image --disable-validation --skip-root-tests
+    assertEquals "build_image_env(true,true)" "$(cat $STDOUTF)"
+}
+function test_check_env(){
+    assertCommandSuccess cli -c myscript
+    assertEquals "check_env(${JUNEST_HOME},myscript,false)" "$(cat $STDOUTF)"
+    assertCommandSuccess cli --check myscript
+    assertEquals "check_env(${JUNEST_HOME},myscript,false)" "$(cat $STDOUTF)"
+    assertCommandSuccess cli -c myscript -s
+    assertEquals "check_env(${JUNEST_HOME},myscript,true)" "$(cat $STDOUTF)"
+    assertCommandSuccess cli --check myscript --skip-root-tests
+    assertEquals "check_env(${JUNEST_HOME},myscript,true)" "$(cat $STDOUTF)"
+}
+function test_delete_env(){
+    assertCommandSuccess cli -d
+    assertEquals "delete_env" "$(cat $STDOUTF)"
+    assertCommandSuccess cli --delete
+    assertEquals "delete_env" "$(cat $STDOUTF)"
+}
+function test_setup_env_from_file(){
+    is_env_installed(){
+        return 1
+    }
+    assertCommandSuccess cli -i myimage
+    assertEquals "$(echo -e "setup_env_from_file(myimage)\nrun_env_as_user(,)")" "$(cat $STDOUTF)"
+    assertCommandSuccess cli --setup-from-file myimage
+    assertEquals "$(echo -e "setup_env_from_file(myimage)\nrun_env_as_user(,)")" "$(cat $STDOUTF)"
+
+    is_env_installed(){
+        return 0
+    }
+    assertCommandFail cli -i myimage
+}
+
+function test_setup_env(){
+    is_env_installed(){
+        return 1
+    }
+    assertCommandSuccess cli -a arm
+    assertEquals "$(echo -e "setup_env(arm)\nrun_env_as_user(,)")" "$(cat $STDOUTF)"
+    assertCommandSuccess cli --arch arm
+    assertEquals "$(echo -e "setup_env(arm)\nrun_env_as_user(,)")" "$(cat $STDOUTF)"
+    assertCommandSuccess cli
+    assertEquals "$(echo -e "setup_env()\nrun_env_as_user(,)")" "$(cat $STDOUTF)"
+
+    is_env_installed(){
+        return 0
+    }
+    assertCommandFail cli -a arm
+}
+function test_run_env_as_fakeroot(){
+    assertCommandSuccess cli -f
+    assertEquals "run_env_as_fakeroot(,)" "$(cat $STDOUTF)"
+    assertCommandSuccess cli --fakeroot
+    assertEquals "run_env_as_fakeroot(,)" "$(cat $STDOUTF)"
+
+    assertCommandSuccess cli -f -p "-b arg"
+    assertEquals "run_env_as_fakeroot(-b arg,)" "$(cat $STDOUTF)"
+    assertCommandSuccess cli -f -p "-b arg" -- command -kv
+    assertEquals "run_env_as_fakeroot(-b arg,command -kv)" "$(cat $STDOUTF)"
+    assertCommandSuccess cli -f command --as
+    assertEquals "run_env_as_fakeroot(,command --as)" "$(cat $STDOUTF)"
+    assertCommandFail cli -a "myarch" -f command --as
+}
+function test_run_env_as_user(){
+    assertCommandSuccess cli
+    assertEquals "run_env_as_user(,)" "$(cat $STDOUTF)"
+
+    assertCommandSuccess cli -p "-b arg"
+    assertEquals "run_env_as_user(-b arg,)" "$(cat $STDOUTF)"
+    assertCommandSuccess cli -p "-b arg" -- command -ll
+    assertEquals "run_env_as_user(-b arg,command -ll)" "$(cat $STDOUTF)"
+    assertCommandSuccess cli command -ls
+    assertEquals "run_env_as_user(,command -ls)" "$(cat $STDOUTF)"
+
+    assertCommandFail cli -a "myarch" -- command -ls
+}
+function test_run_env_as_root(){
+    assertCommandSuccess cli -r
+    assertEquals "run_env_as_root " "$(cat $STDOUTF)"
+    assertCommandSuccess cli -r command
+    assertEquals "run_env_as_root command" "$(cat $STDOUTF)"
+}
+
+function test_check_cli(){
+    assertCommandFail cli -b -h
+    assertCommandFail cli -b -c
+    assertCommandFail cli -d -s
+    assertCommandFail cli -n -v
+    assertCommandFail cli -d -r
+    assertCommandFail cli -h -f
+    assertCommandFail cli -v -i fsd
+    assertCommandFail cli -f -r
+    assertCommandFail cli -p args -v
+    assertCommandFail cli -a arch -v
+    assertCommandFail cli -d args
+}
+
+source $(dirname $0)/shunit2
diff --git a/tests/unit-tests/test-core.sh b/tests/unit-tests/test-core.sh
new file mode 100755
index 0000000..46072e1
--- /dev/null
+++ b/tests/unit-tests/test-core.sh
@@ -0,0 +1,292 @@
+#!/bin/bash
+
+JUNEST_ROOT=$(readlink -f $(dirname $0)/../..)
+
+source "$JUNEST_ROOT/tests/unit-tests/utils.sh"
+
+# Disable the exiterr
+set +e
+
+function oneTimeSetUp(){
+    SKIP_ROOT_TESTS=${SKIP_ROOT_TESTS:-0}
+    setUpUnitTests
+}
+
+function setUp(){
+    ORIGIN_CWD=$(TMPDIR=/tmp mktemp -d -t junest-cwd.XXXXXXXXXX)
+    cd $ORIGIN_CWD
+    JUNEST_HOME=$(TMPDIR=/tmp mktemp -d -t junest-home.XXXXXXXXXX)
+    mkdir -p ${JUNEST_HOME}/etc/junest
+    echo "JUNEST_ARCH=x86_64" > ${JUNEST_HOME}/etc/junest/info
+    mkdir -p ${JUNEST_HOME}/etc/ca-certificates
+    JUNEST_TEMPDIR=$(TMPDIR=/tmp mktemp -d -t junest-temp.XXXXXXXXXX)
+    source "$JUNEST_ROOT/lib/utils.sh"
+    source "$JUNEST_ROOT/lib/core.sh"
+
+    set +e
+
+    trap - QUIT EXIT ABRT KILL TERM INT
+    trap "rm -rf ${JUNEST_HOME}; rm -rf ${JUNEST_TEMPDIR}" EXIT QUIT ABRT KILL TERM INT
+
+    ld_exec() {
+        echo "ld_exec $@"
+    }
+    LD_EXEC=ld_exec
+}
+
+
+function tearDown(){
+    # the CA directories are read only and can be deleted only by changing the mod
+    [ -d ${JUNEST_HOME}/etc/ca-certificates ] && chmod -R +w ${JUNEST_HOME}/etc/ca-certificates
+    rm -rf $JUNEST_HOME
+    rm -rf $JUNEST_TEMPDIR
+    rm -rf $ORIGIN_CWD
+    trap - QUIT EXIT ABRT KILL TERM INT
+}
+
+
+function test_ln(){
+    LN=echo assertCommandSuccess ln_cmd -s ln_file new_file
+    assertEquals "-s ln_file new_file" "$(cat $STDOUTF)"
+
+    LN=false assertCommandSuccess ln_cmd -s ln_file new_file
+    assertEquals "ld_exec ${JUNEST_HOME}/usr/bin/false -s ln_file new_file" "$(cat $STDOUTF)"
+
+    LN=false LD_EXEC=false assertCommandFail ln_cmd
+}
+
+function test_download(){
+    WGET=/bin/true
+    CURL=/bin/false
+    assertCommandSuccess download_cmd
+
+    WGET=/bin/false
+    CURL=/bin/true
+    assertCommandSuccess download_cmd
+
+    WGET=/bin/false CURL=/bin/false assertCommandFail download_cmd
+}
+
+function test_rm(){
+    RM=echo assertCommandSuccess rm_cmd rm_file
+    assertEquals "rm_file" "$(cat $STDOUTF)"
+
+    RM=false assertCommandSuccess rm_cmd rm_file
+    assertEquals "ld_exec ${JUNEST_HOME}/usr/bin/false rm_file" "$(cat $STDOUTF)"
+
+    RM=false LD_EXEC=false assertCommandFail rm_cmd rm_file
+}
+
+function test_chown(){
+    local id=$(id -u)
+
+    CHOWN=echo assertCommandSuccess chown_cmd $id chown_file
+    assertEquals "$id chown_file" "$(cat $STDOUTF)"
+
+    CHOWN=false assertCommandSuccess chown_cmd $id chown_file
+    assertEquals "ld_exec ${JUNEST_HOME}/usr/bin/false $id chown_file" "$(cat $STDOUTF)"
+
+    CHOWN=false LD_EXEC=false assertCommandFail chown_cmd $id chown_file
+}
+
+function test_mkdir(){
+    MKDIR=echo assertCommandSuccess mkdir_cmd -p new_dir/new_dir
+    assertEquals "-p new_dir/new_dir" "$(cat $STDOUTF)"
+
+    MKDIR=false assertCommandSuccess mkdir_cmd -p new_dir/new_dir
+    assertEquals "ld_exec ${JUNEST_HOME}/usr/bin/false -p new_dir/new_dir" "$(cat $STDOUTF)"
+
+    MKDIR=false LD_EXEC=false assertCommandFail mkdir_cmd -p new_dir/new_dir
+}
+
+function test_chroot(){
+    CHROOT=echo assertCommandSuccess chroot_cmd root
+    assertEquals "root" "$(cat $STDOUTF)"
+
+    CHROOT=false CLASSIC_CHROOT=echo assertCommandSuccess chroot_cmd root
+    assertEquals "root" "$(cat $STDOUTF)"
+
+    CHROOT=false CLASSIC_CHROOT=false assertCommandSuccess chroot_cmd root
+    assertEquals "ld_exec $JUNEST_HOME/usr/bin/chroot root" "$(cat $STDOUTF)"
+
+    CHROOT=false CLASSIC_CHROOT=false LD_EXEC=false assertCommandFail chroot_cmd root
+}
+
+function test_proot_cmd_compat(){
+    PROOT="/bin/true" assertCommandSuccess proot_cmd "" ""
+
+    PROOT="/bin/false" assertCommandFail proot_cmd --helps
+}
+
+function test_proot_cmd_seccomp(){
+    envv(){
+        env
+    }
+    PROOT=envv
+    assertCommandSuccess proot_cmd cmd
+    assertEquals "" "$(cat $STDOUTF | grep "^PROOT_NO_SECCOMP")"
+
+    envv(){
+        env | grep "^PROOT_NO_SECCOMP"
+    }
+    PROOT=envv
+    local output=$(proot_cmd | grep "^PROOT_NO_SECCOMP")
+    assertCommandSuccess proot_cmd cmd
+    # The variable PROOT_NO_SECCOMP will be produced
+    # twice due to the fallback mechanism
+    assertEquals "PROOT_NO_SECCOMP=1
+PROOT_NO_SECCOMP=1" "$(cat $STDOUTF | grep "^PROOT_NO_SECCOMP")"
+}
+
+function test_is_env_installed(){
+    rm -rf $JUNEST_HOME/*
+    assertCommandFail is_env_installed
+    touch $JUNEST_HOME/just_file
+    assertCommandSuccess is_env_installed
+}
+
+function test_setup_env(){
+    rm -rf $JUNEST_HOME/*
+    wget_mock(){
+        # Proof that the setup is happening
+        # inside $JUNEST_TEMPDIR
+        local cwd=${PWD#${JUNEST_TEMPDIR}}
+        local parent_dir=${PWD%${cwd}}
+        assertEquals "$JUNEST_TEMPDIR" "${parent_dir}"
+        touch file
+        tar -czvf ${CMD}-${ARCH}.tar.gz file
+    }
+    WGET=wget_mock
+    setup_env 1> /dev/null
+    assertTrue "[ -e $JUNEST_HOME/file ]"
+
+    assertCommandFailOnStatus 102 setup_env "noarch"
+}
+
+
+function test_setup_env_from_file(){
+    rm -rf $JUNEST_HOME/*
+    touch file
+    tar -czvf ${CMD}-${ARCH}.tar.gz file 1> /dev/null
+    assertCommandSuccess setup_env_from_file ${CMD}-${ARCH}.tar.gz
+    assertTrue "[ -e $JUNEST_HOME/file ]"
+}
+
+function test_setup_env_from_file_not_existing_file(){
+    assertCommandFailOnStatus 103 setup_env_from_file noexist.tar.gz
+}
+
+function test_setup_env_from_file_with_absolute_path(){
+    rm -rf $JUNEST_HOME/*
+    touch file
+    tar -czvf ${CMD}-${ARCH}.tar.gz file 1> /dev/null
+    assertCommandSuccess setup_env_from_file ${ORIGIN_WD}/${CMD}-${ARCH}.tar.gz
+    assertTrue "[ -e $JUNEST_HOME/file ]"
+}
+
+function test_run_env_as_root_different_arch(){
+    echo "JUNEST_ARCH=XXX" > ${JUNEST_HOME}/etc/junest/info
+    assertCommandFailOnStatus 104 run_env_as_root pwd
+}
+
+function _test_run_env_as_root() {
+    chroot_cmd() {
+        [ "$JUNEST_ENV" != "1" ] && return 1
+        echo $@
+    }
+
+    assertCommandSuccess run_env_as_root $@
+}
+
+function test_run_env_as_root_cmd(){
+    _test_run_env_as_root pwd
+    assertEquals "$JUNEST_HOME /bin/sh --login -c pwd" "$(cat $STDOUTF)"
+}
+
+function test_run_env_as_classic_root_no_cmd(){
+    _test_run_env_as_root
+    assertEquals "$JUNEST_HOME /bin/sh --login -c /bin/sh --login" "$(cat $STDOUTF)"
+}
+
+function test_run_env_as_user(){
+    _run_env_with_qemu() {
+        echo $@
+    }
+    assertCommandSuccess run_env_as_user "-k 3.10" "/usr/bin/mkdir" "-v" "/newdir2"
+    _provide_bindings_as_user
+    assertEquals "${RESULT}-r ${JUNEST_HOME} -k 3.10 /usr/bin/mkdir -v /newdir2" "$(cat $STDOUTF)"
+
+    SH=("/usr/bin/echo")
+    assertCommandSuccess run_env_as_user "-k 3.10"
+    _provide_bindings_as_user
+    assertEquals "${RESULT}-r ${JUNEST_HOME} -k 3.10" "$(cat $STDOUTF)"
+}
+
+function test_run_env_as_fakeroot(){
+    _run_env_with_qemu() {
+        echo $@
+    }
+    assertCommandSuccess run_env_as_fakeroot "-k 3.10" "/usr/bin/mkdir" "-v" "/newdir2"
+    assertEquals "-S ${JUNEST_HOME} -k 3.10 /usr/bin/mkdir -v /newdir2" "$(cat $STDOUTF)"
+
+    SH=("/usr/bin/echo")
+    assertCommandSuccess run_env_as_fakeroot "-k 3.10"
+    assertEquals "-S ${JUNEST_HOME} -k 3.10" "$(cat $STDOUTF)"
+}
+
+function test_run_env_with_quotes(){
+    _run_env_with_qemu() {
+        echo $@
+    }
+    assertCommandSuccess run_env_as_user "-k 3.10" "bash" "-c" "/usr/bin/mkdir -v /newdir2"
+    _provide_bindings_as_user
+    assertEquals "${RESULT}-r ${JUNEST_HOME} -k 3.10 bash -c /usr/bin/mkdir -v /newdir2" "$(cat $STDOUTF)"
+}
+
+function test_run_env_with_proot_args(){
+    proot_cmd() {
+        [ "$JUNEST_ENV" != "1" ] && return 1
+        echo $@
+    }
+
+    assertCommandSuccess _run_env_with_proot --help
+    assertEquals "--help /bin/sh --login" "$(cat $STDOUTF)"
+
+    assertCommandSuccess _run_env_with_proot --help mycommand
+    assertEquals "--help /bin/sh --login -c mycommand" "$(cat $STDOUTF)"
+
+    assertCommandFail _run_env_with_proot
+}
+
+function test_delete_env(){
+    echo "N" | delete_env 1> /dev/null
+    assertCommandSuccess is_env_installed
+    echo "Y" | delete_env 1> /dev/null
+    assertCommandFail is_env_installed
+}
+
+function test_nested_env(){
+    JUNEST_ENV=1 assertCommandFailOnStatus 106 bash -ic "source $JUNEST_ROOT/lib/utils.sh; source $JUNEST_ROOT/lib/core.sh"
+}
+
+function test_nested_env_not_set_variable(){
+    JUNEST_ENV=aaa assertCommandFailOnStatus 107 bash -ic "source $JUNEST_ROOT/lib/utils.sh; source $JUNEST_ROOT/lib/core.sh"
+}
+
+function test_qemu() {
+    echo "JUNEST_ARCH=arm" > ${JUNEST_HOME}/etc/junest/info
+    rm_cmd() {
+        echo $@
+    }
+    ln_cmd() {
+        echo $@
+    }
+    _run_env_with_proot() {
+        echo $@
+    }
+
+    RANDOM=100 ARCH=x86_64 assertCommandSuccess _run_env_with_qemu ""
+    assertEquals "$(echo -e "-s $JUNEST_HOME/opt/qemu/qemu-arm-static-x86_64 /tmp/qemu-arm-static-x86_64-100\n-q /tmp/qemu-arm-static-x86_64-100")" "$(cat $STDOUTF)"
+}
+
+source $JUNEST_ROOT/tests/unit-tests/shunit2
diff --git a/tests/unit-tests/test-utils.sh b/tests/unit-tests/test-utils.sh
new file mode 100755
index 0000000..5816d11
--- /dev/null
+++ b/tests/unit-tests/test-utils.sh
@@ -0,0 +1,97 @@
+#!/bin/bash
+source "$(dirname $0)/utils.sh"
+
+unset HOME
+export HOME=$(TMPDIR=/tmp mktemp -d -t pearl-user-home.XXXXXXX)
+
+source "$(dirname $0)/../../lib/utils.sh"
+
+# Disable the exiterr
+set +e
+
+function oneTimeSetUp(){
+    setUpUnitTests
+}
+
+function test_check_not_null(){
+    assertCommandFailOnStatus 11 check_not_null "" ""
+    assertCommandSuccess check_not_null "bla" ""
+}
+
+function test_echoerr(){
+    assertCommandSuccess echoerr "Test"
+    assertEquals "Test" "$(cat $STDERRF)"
+}
+
+function test_error(){
+    assertCommandSuccess error "Test"
+    local expected=$(echo -e "\033[1;31mTest\033[0m")
+    assertEquals "$expected" "$(cat $STDERRF)"
+}
+
+function test_warn(){
+    assertCommandSuccess warn "Test"
+    local expected=$(echo -e "\033[1;33mTest\033[0m")
+    assertEquals "$expected" "$(cat $STDERRF)"
+}
+
+function test_info(){
+    assertCommandSuccess info "Test"
+    local expected=$(echo -e "\033[1;36mTest\033[0m")
+    assertEquals "$expected" "$(cat $STDOUTF)"
+}
+
+function test_die(){
+    assertCommandFail die "Test"
+    local expected=$(echo -e "\033[1;31mTest\033[0m")
+    assertEquals "$expected" "$(cat $STDERRF)"
+}
+
+function test_die_on_status(){
+    assertCommandFailOnStatus 222 die_on_status 222 "Test"
+    local expected=$(echo -e "\033[1;31mTest\033[0m")
+    assertEquals "$expected" "$(cat $STDERRF)"
+}
+
+function test_ask_null_question(){
+    assertCommandFailOnStatus 11 ask "" "Y"
+}
+
+function test_ask(){
+    echo "Y" | ask "Test" &> /dev/null
+    assertEquals 0 $?
+    echo "y" | ask "Test" &> /dev/null
+    assertEquals 0 $?
+    echo "N" | ask "Test" &> /dev/null
+    assertEquals 1 $?
+    echo "n" | ask "Test" &> /dev/null
+    assertEquals 1 $?
+    echo -e "\n" | ask "Test" &> /dev/null
+    assertEquals 0 $?
+    echo -e "\n" | ask "Test" "N" &> /dev/null
+    assertEquals 1 $?
+    echo -e "asdf\n\n" | ask "Test" "N" &> /dev/null
+    assertEquals 1 $?
+}
+
+function test_ask_wrong_default_answer() {
+    echo "Y" | ask "Test" G &> /dev/null
+    assertEquals 33 $?
+}
+
+function test_insert_quotes_on_spaces(){
+    assertCommandSuccess insert_quotes_on_spaces this is "a test"
+    assertEquals "this is \"a test\"" "$(cat $STDOUTF)"
+
+    assertCommandSuccess insert_quotes_on_spaces this is 'a test'
+    assertEquals "this is \"a test\"" "$(cat $STDOUTF)"
+}
+
+function test_contains_element(){
+    array=("something to search for" "a string" "test2000")
+    assertCommandSuccess contains_element "a string" "${array[@]}"
+
+    assertCommandFailOnStatus 1 contains_element "blabla" "${array[@]}"
+}
+
+source $(dirname $0)/shunit2
diff --git a/tests/unit-tests.sh b/tests/unit-tests/unit-tests.sh
similarity index 100%
rename from tests/unit-tests.sh
rename to tests/unit-tests/unit-tests.sh
diff --git a/tests/unit-tests/utils.sh b/tests/unit-tests/utils.sh
new file mode 100644
index 0000000..b12420e
--- /dev/null
+++ b/tests/unit-tests/utils.sh
@@ -0,0 +1,32 @@
+
+function setUpUnitTests(){
+    OUTPUT_DIR="${SHUNIT_TMPDIR}/output"
+    mkdir "${OUTPUT_DIR}"
+    STDOUTF="${OUTPUT_DIR}/stdout"
+    STDERRF="${OUTPUT_DIR}/stderr"
+}
+
+function assertCommandSuccess(){
+    $(set -e
+      "$@" > $STDOUTF 2> $STDERRF
+    )
+    assertTrue "The command $1 did not return 0 exit status" $?
+}
+
+function assertCommandFail(){
+    $(set -e
+      "$@" > $STDOUTF 2> $STDERRF
+    )
+    assertFalse "The command $1 returned 0 exit status" $?
+}
+
+# $1: expected exit status
+# $2-: The command under test
+function assertCommandFailOnStatus(){
+    local status=$1
+    shift
+    $(set -e
+      "$@" > $STDOUTF 2> $STDERRF
+    )
+    assertEquals $status $?
+}