diff --git a/bin/juju b/bin/juju
index 8f12cdc..c00da88 100755
--- a/bin/juju
+++ b/bin/juju
@@ -105,79 +105,74 @@ check_cli(){
 }
 
 
-###################################
-### MAIN PROGRAM                ###
-###################################
+function parse_arguments(){
+    TEMP=$(getopt -o drp:fbi:hv --long delete,root,proot-args:,fakeroot,build-image,setup-from-file:,help,version -n 'juju' -- "$@")
+	eval set -- "$TEMP"
 
-TEMP=`getopt -o drp:fbi:hv --long delete,root,proot-args:,fakeroot,build-image,setup-from-file:,help,version -n 'juju' -- "$@"`
+	OPT_SETUP_FROM_FILE=false
+	IMAGE_FILE=""
+	OPT_FAKEROOT=false
+	OPT_ROOT=false
+	OPT_PROOT_ARGS=false
+	PROOT_ARGS=""
+	OPT_BUILD_IMAGE=false
+	OPT_DELETE=false
+	OPT_HELP=false
+	OPT_VERSION=false
+	while true ; 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 ;;
+			-b|--build-image) OPT_BUILD_IMAGE=true ; shift ;;
+			-d|--delete) OPT_DELETE=true ; shift ;;
+			-h|--help) OPT_HELP=true ; shift ;;
+			-v|--version) OPT_VERSION=true ; shift ;;
+			--) shift ; break ;;
+			*) die "Internal error!" ;;
+		esac
+	done
 
-if [ $? != 0 ] ; then error "Error on parsing the command line. Try juju -h." ; exit ; fi
+	ARGS=()
+	for arg do
+		ARGS+=($arg)
+	done
+}
 
-# Note the quotes around `$TEMP': they are essential!
-eval set -- "$TEMP"
+function execute_operation(){
+	$OPT_HELP && usage && return
+	$OPT_VERSION && version && return
 
-OPT_SETUP_FROM_FILE=false
-IMAGE_FILE=""
-OPT_FAKEROOT=false
-OPT_ROOT=false
-OPT_PROOT_ARGS=false
-PROOT_ARGS=""
-OPT_BUILD_IMAGE=false
-OPT_DELETE=false
-OPT_HELP=false
-OPT_VERSION=false
-while true ; 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 ;;
-        -b|--build-image) OPT_BUILD_IMAGE=true ; shift ;;
-        -d|--delete) OPT_DELETE=true ; shift ;;
-        -h|--help) OPT_HELP=true ; shift ;;
-        -v|--version) OPT_VERSION=true ; shift ;;
-        --) shift ; break ;;
-        *) error "Internal error!" ; exit 1 ;;
-    esac
-done
+	if $OPT_BUILD_IMAGE; then
+		build_image_juju
+		return
+	elif $OPT_DELETE; then
+		delete_juju
+		return
+	fi
 
-ARGS=()
-for arg do
-    ARGS+=($arg)
-done
+	if ! is_juju_installed
+	then
+		if $OPT_SETUP_FROM_FILE; then
+			setup_from_file_juju $IMAGE_FILE
+		else
+			setup_juju
+		fi
+	elif $OPT_SETUP_FROM_FILE; then
+		die "Error: The image cannot be installed since $JUJU_HOME is not empty."
+	fi
 
-check_cli || exit 1
-
-################ DEFINE ACTION ########################
-
-$OPT_HELP && usage && exit
-$OPT_VERSION && version && exit
-
-if $OPT_BUILD_IMAGE; then
-    build_image_juju
-    exit
-elif $OPT_DELETE; then
-    delete_juju
-    exit
-fi
-
-if ! is_juju_installed
-then
-    if $OPT_SETUP_FROM_FILE; then
-        setup_from_file_juju $IMAGE_FILE
-    else
-        setup_juju
-    fi
-elif $OPT_SETUP_FROM_FILE; then
-	die "Error: The image cannot be installed since $JUJU_HOME is not empty."
-fi
-
-if $OPT_FAKEROOT; then
-    run_juju_as_fakeroot "${PROOT_ARGS}" ${ARGS[@]}
-elif $OPT_ROOT; then
-    run_juju_as_root ${ARGS[@]}
-else
-    run_juju_as_user "${PROOT_ARGS}" ${ARGS[@]}
-fi
+	if $OPT_FAKEROOT; then
+		run_juju_as_fakeroot "${PROOT_ARGS}" ${ARGS[@]}
+	elif $OPT_ROOT; then
+		run_juju_as_root ${ARGS[@]}
+	else
+		run_juju_as_user "${PROOT_ARGS}" ${ARGS[@]}
+	fi
+}
 
+parse_arguments $@
+check_cli
+execute_operation
 # vim: set ts=4 sw=4 noet:
diff --git a/lib/core.sh b/lib/core.sh
index 631931d..c6cc042 100644
--- a/lib/core.sh
+++ b/lib/core.sh
@@ -75,6 +75,10 @@ then
 else
     die "The variable JUJU_ENV is not properly set"
 fi
+
+CHROOT=${JUJU_HOME}/usr/bin/arch-chroot
+TRUE=${JUJU_HOME}/usr/bin/true
+
 ################################# MAIN FUNCTIONS ##############################
 
 function is_juju_installed(){
@@ -160,12 +164,12 @@ function run_juju_as_root(){
     [ "$JUJU_ENV" == "1" ] && die "Error: The operation is not allowed inside JuJu environment"
 
     mkdir -p ${JUJU_HOME}/${HOME}
-    ${JUJU_HOME}/usr/bin/arch-chroot $JUJU_HOME /usr/bin/bash -c "mkdir -p /run/lock && $(_define_chroot_args "$@")"
+    ${CHROOT} $JUJU_HOME /usr/bin/bash -c "mkdir -p /run/lock && $(_define_chroot_args "$@")"
 }
 
 
 function _run_juju_with_proot(){
-    if ${PROOT} ${JUJU_HOME}/usr/bin/true &> /dev/null
+    if ${PROOT} ${TRUE} &> /dev/null
     then
         JUJU_ENV=1 ${PROOT} $@
     else
diff --git a/lib/util.sh b/lib/util.sh
index 15fd48c..dc88506 100644
--- a/lib/util.sh
+++ b/lib/util.sh
@@ -17,7 +17,9 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-echoerr() { echo "$@" 1>&2; }
+function echoerr(){
+    echo "$@" 1>&2
+}
 function die(){
 # $@: msg (mandatory) - str: Message to print
     error $@
diff --git a/tests/test_all.sh b/tests/test_all.sh
new file mode 100755
index 0000000..684e6fd
--- /dev/null
+++ b/tests/test_all.sh
@@ -0,0 +1,5 @@
+
+for tst in $(ls $(dirname $0)/test_* | grep -v $(basename $0))
+do
+    $tst
+done
diff --git a/tests/test_core.sh b/tests/test_core.sh
new file mode 100755
index 0000000..5c85925
--- /dev/null
+++ b/tests/test_core.sh
@@ -0,0 +1,163 @@
+#!/bin/bash
+# To test this module you need to run it inside a Archlinux system. Also, the following packages needs to be installed:
+# bash
+# pacman
+# arch-install-scripts
+# proot
+# coreutils
+# grep
+# sudo
+# gawk
+
+source "$(dirname $0)/utils.sh"
+CURRPWD=$PWD
+JUJU_HOME=""
+
+function set_up(){
+    cd $CURRPWD
+    JUJU_HOME=$(TMPDIR=/tmp mktemp -d -t jujuhome.XXXXXXXXXX)
+    source "$(dirname $0)/../lib/core.sh"
+    ORIGIN_WD=$(TMPDIR=/tmp mktemp -d -t jujuowd.XXXXXXXXXX)
+    cd $ORIGIN_WD
+    JUJU_TEMPDIR=$(TMPDIR=/tmp mktemp -d -t jujutemp.XXXXXXXXXX)
+
+    trap - QUIT EXIT ABRT KILL TERM INT
+    trap "rm -rf ${JUJU_HOME}; rm -rf ${ORIGIN_WD}; rm -rf ${JUJU_TEMPDIR}" EXIT QUIT ABRT KILL TERM INT
+}
+
+
+function tear_down(){
+    rm -rf $JUJU_HOME
+    rm -rf $ORIGIN_WD
+    rm -rf $JUJU_TEMPDIR
+    trap - QUIT EXIT ABRT KILL TERM INT
+}
+
+function test_is_juju_installed(){
+    is_juju_installed
+    is_equal $? 1 || return 1
+    touch $JUJU_HOME/just_file
+    is_juju_installed
+    is_equal $? 0 || return 1
+}
+
+
+function test_setup_juju(){
+    wget_mock(){
+        # Proof that the setup is happening
+        # inside $JUJU_TEMPDIR
+        local cwd=${PWD#${JUJU_TEMPDIR}}
+        local parent_dir=${PWD%${cwd}}
+        is_equal $JUJU_TEMPDIR ${parent_dir} || return 1
+        touch file
+        tar -czvf juju-${ARCH}.tar.gz file
+    }
+    WGET=wget_mock
+    setup_juju 1> /dev/null
+    [ -e $JUJU_HOME/file ] || return 1
+    [ -e $JUJU_HOME/run/lock ] || return 1
+
+    export -f setup_juju
+    JUJU_ENV=1 bash -ic "setup_juju" &> /dev/null
+    is_equal $? 1 || return 1
+}
+
+
+function test_setup_from_file_juju(){
+    touch file
+    tar -czvf juju-${ARCH}.tar.gz file 1> /dev/null
+    setup_from_file_juju juju-${ARCH}.tar.gz 1> /dev/null
+    [ -e $JUJU_HOME/file ] || return 1
+    [ -e $JUJU_HOME/run/lock ] || return 1
+
+    export -f setup_from_file_juju
+    bash -ic "setup_from_file_juju noexist.tar.gz" &> /dev/null
+    is_equal $? 1 || return 1
+
+    export -f setup_from_file_juju
+    JUJU_ENV=1 bash -ic "setup_from_file_juju" &> /dev/null
+    is_equal $? 1 || return 1
+}
+
+
+function test_run_juju_as_root(){
+    install_mini_juju
+    CHROOT="sudo $CHROOT"
+    SH="type -t type"
+    local output=$(run_juju_as_root)
+    is_equal $output "builtin" || return 1
+    local output=$(run_juju_as_root pwd)
+    is_equal $output "/" || return 1
+    run_juju_as_root "[ -e /run/lock ]"
+    is_equal $? 0 || return 1
+    [ -e $JUJU_HOME/${HOME} ] || return 1
+
+    export -f run_juju_as_root
+    JUJU_ENV=1 bash -ic "run_juju_as_root" &> /dev/null
+    is_equal $? 1 || return 1
+}
+
+function test_run_juju_as_user(){
+    install_mini_juju
+    local output=$(run_juju_as_user "" "mkdir -v /newdir2")
+    is_equal "$output" "/usr/bin/mkdir: created directory '/newdir2'" || return 1
+    [ -e $JUJU_HOME/newdir2 ]
+    is_equal $? 0 || return 1
+
+    SH="mkdir -v /newdir"
+    local output=$(run_juju_as_user "")
+    is_equal "$output" "/usr/bin/mkdir: created directory '/newdir'" || return 1
+    [ -e $JUJU_HOME/newdir ]
+    is_equal $? 0 || return 1
+}
+
+function test_run_juju_as_user_proot_args(){
+    install_mini_juju
+    run_juju_as_user "--help" "" 1> /dev/null
+    is_equal $? 0 || return 1
+    run_juju_as_user "--helps" "" &> /dev/null
+    is_equal $? 1 || return 1
+
+    mkdir $JUJU_TEMPDIR/newdir
+    touch $JUJU_TEMPDIR/newdir/newfile
+    run_juju_as_user "-b $JUJU_TEMPDIR/newdir:/newdir" "ls -l /newdir/newfile" 1> /dev/null
+    is_equal $? 0 || return 1
+}
+
+function test_run_juju_as_user_seccomp(){
+    install_mini_juju
+    local output=$(run_juju_as_user "" "env" | grep "PROOT_NO_SECCOMP")
+    is_equal $output "" || return 1
+
+    TRUE="/usr/bin/false"
+    local output=$(run_juju_as_user "" "env" | grep "PROOT_NO_SECCOMP")
+    is_equal $output "PROOT_NO_SECCOMP=1" || return 1
+}
+
+function test_run_juju_as_fakeroot(){
+    install_mini_juju
+    local output=$(run_juju_as_fakeroot "" "id" | awk '{print $1}')
+    is_equal "$output" "uid=0" || return 1
+}
+
+function test_delete_juju(){
+    install_mini_juju
+    echo "N" | delete_juju 1> /dev/null
+    is_juju_installed
+    is_equal $? 0 || return 1
+    echo "Y" | delete_juju 1> /dev/null
+    is_juju_installed
+    is_equal $? 1 || return 1
+
+    export -f delete_juju
+    JUJU_ENV=1 bash -ic "delete_juju" &> /dev/null
+    is_equal $? 1 || return 1
+}
+
+
+for func in $(declare -F | grep test_ | awk '{print $3}' | xargs)
+do
+    set_up
+    $func && echo -e "${func}...\033[1;32mOK\033[0m" || echo -e "${func}...\033[1;31mFAIL\033[0m"
+    tear_down
+done
diff --git a/tests/test_juju.sh b/tests/test_juju.sh
new file mode 100755
index 0000000..8d9a94a
--- /dev/null
+++ b/tests/test_juju.sh
@@ -0,0 +1,134 @@
+#!/bin/bash
+source "$(dirname $0)/utils.sh"
+source $(dirname $0)/../bin/juju -h &> /dev/null
+## Mock functions ##
+function usage(){
+    echo "usage"
+}
+function version(){
+    echo "version"
+}
+function build_image_juju(){
+    echo "build_image_juju"
+}
+function delete_juju(){
+    echo "delete_juju"
+}
+function is_juju_installed(){
+    return 0
+}
+function setup_from_file_juju(){
+    echo "setup_from_file_juju $@"
+}
+function setup_juju(){
+    echo "setup_juju"
+}
+function run_juju_as_fakeroot(){
+    echo "run_juju_as_fakeroot $@"
+}
+function run_juju_as_root(){
+    echo "run_juju_as_root $@"
+}
+function run_juju_as_user(){
+    echo "run_juju_as_user $@"
+}
+
+function wrap_juju(){
+    parse_arguments $@
+    check_cli
+    execute_operation
+}
+
+
+function set_up(){
+    echo > /dev/null
+}
+
+function tear_down(){
+    echo > /dev/null
+}
+
+
+function test_help(){
+    local output=$(wrap_juju -h)
+    is_equal $output "usage" || return 1
+    local output=$(wrap_juju --help)
+    is_equal $output "usage" || return 1
+}
+function test_version(){
+    local output=$(wrap_juju -v)
+    is_equal $output "version" || return 1
+    local output=$(wrap_juju --version)
+    is_equal $output "version" || return 1
+}
+function test_build_image_juju(){
+    local output=$(wrap_juju -b)
+    is_equal $output "build_image_juju" || return 1
+    local output=$(wrap_juju --build-image)
+    is_equal $output "build_image_juju" || return 1
+}
+function test_delete_juju(){
+    local output=$(wrap_juju -d)
+    is_equal $output "delete_juju" || return 1
+    local output=$(wrap_juju --delete)
+    is_equal $output "delete_juju" || return 1
+}
+function test_run_juju_as_fakeroot(){
+    local output=$(wrap_juju -f)
+    is_equal $output "run_juju_as_fakeroot" || return 1
+    local output=$(wrap_juju --fakeroot)
+    is_equal $output "run_juju_as_fakeroot" || return 1
+
+    local output=$(wrap_juju -f -p "-b arg")
+    is_equal "${output[@]}" "run_juju_as_fakeroot -b arg" || return 1
+    local output=$(wrap_juju -f -p "-b arg" -- command)
+    is_equal "${output[@]}" "run_juju_as_fakeroot -b arg command" || return 1
+    local output=$(wrap_juju -f command)
+    is_equal "${output[@]}" "run_juju_as_fakeroot  command" || return 1
+}
+function test_run_juju_as_user(){
+    local output=$(wrap_juju)
+    is_equal $output "run_juju_as_user" || return 1
+
+    local output=$(wrap_juju -p "-b arg")
+    is_equal "${output[@]}" "run_juju_as_user -b arg" || return 1
+    local output=$(wrap_juju -p "-b arg" -- command)
+    is_equal "${output[@]}" "run_juju_as_user -b arg command" || return 1
+    local output=$(wrap_juju command)
+    is_equal "${output[@]}" "run_juju_as_user  command" || return 1
+}
+function test_run_juju_as_root(){
+    local output=$(wrap_juju -r)
+    is_equal $output "run_juju_as_root" || return 1
+
+    local output=$(wrap_juju -r command)
+    is_equal "${output[@]}" "run_juju_as_root command" || return 1
+}
+
+function test_check_cli(){
+    export -f check_cli
+    export -f parse_arguments
+    export -f execute_operation
+    export -f wrap_juju
+    bash -ic "wrap_juju -b -h" &> /dev/null
+    is_equal $? 1 || return 1
+    bash -ic "wrap_juju -d -r" &> /dev/null
+    is_equal $? 1 || return 1
+    bash -ic "wrap_juju -h -f" &> /dev/null
+    is_equal $? 1 || return 1
+    bash -ic "wrap_juju -v -i fsd" &> /dev/null
+    is_equal $? 1 || return 1
+    bash -ic "wrap_juju -f -r" &> /dev/null
+    is_equal $? 1 || return 1
+    bash -ic "wrap_juju -p args -v" &> /dev/null
+    is_equal $? 1 || return 1
+    bash -ic "wrap_juju -d args" &> /dev/null
+    is_equal $? 1 || return 1
+}
+
+for func in $(declare -F | grep test_ | awk '{print $3}' | xargs)
+do
+    set_up
+    $func && echo -e "${func}...\033[1;32mOK\033[0m" || echo -e "${func}...\033[1;31mFAIL\033[0m"
+    tear_down
+done
diff --git a/tests/test_util.sh b/tests/test_util.sh
new file mode 100755
index 0000000..757f08f
--- /dev/null
+++ b/tests/test_util.sh
@@ -0,0 +1,63 @@
+#!/bin/bash
+source "$(dirname $0)/utils.sh"
+source "$(dirname $0)/../lib/util.sh"
+
+function test_echoerr(){
+    local actual=$(echoerr "Test" 2>&1)
+    is_equal "$actual" "Test" || return 1
+    return 0
+}
+
+function test_error(){
+    local actual=$(error "Test" 2>&1)
+    local expected=$(echo -e "\033[1;31mTest\033[0m")
+    is_equal "$actual" "$expected" || return 1
+    return 0
+}
+
+function test_warn(){
+    local actual=$(warn "Test" 2>&1)
+    local expected=$(echo -e "\033[1;33mTest\033[0m")
+    is_equal "$actual" "$expected" || return 1
+    return 0
+}
+
+function test_info(){
+    local actual=$(info "Test")
+    local expected=$(echo -e "\033[1;37mTest\033[0m")
+    is_equal "$actual" "$expected" || return 1
+    return 0
+}
+
+function test_die(){
+    local actual=$(die "Test" 2>&1)
+    local expected=$(echo -e "\033[1;31mTest\033[0m")
+    is_equal "$actual" "$expected" || return 1
+    bash -ic "die Dying" &> /dev/null
+    is_equal $? 1 || return 1
+    return 0
+}
+
+function test_ask(){
+    echo "Y" | ask "Test" &> /dev/null
+    is_equal $? 0 || return 1
+    echo "y" | ask "Test" &> /dev/null
+    is_equal $? 0 || return 1
+    echo "N" | ask "Test" &> /dev/null
+    is_equal $? 1 || return 1
+    echo "n" | ask "Test" &> /dev/null
+    is_equal $? 1 || return 1
+    echo -e "\n" | ask "Test" &> /dev/null
+    is_equal $? 0 || return 1
+    echo -e "\n" | ask "Test" "N" &> /dev/null
+    is_equal $? 1 || return 1
+    echo -e "asdf\n\n" | ask "Test" "N" &> /dev/null
+    is_equal $? 1 || return 1
+    return 0
+}
+
+
+for func in $(declare -F | grep test_ | awk '{print $3}' | xargs)
+do
+    $func && echo -e "${func}...\033[1;32mOK\033[0m" || echo -e "${func}...\033[1;31mFAIL\033[0m"
+done
diff --git a/tests/utils.sh b/tests/utils.sh
new file mode 100644
index 0000000..9f6f263
--- /dev/null
+++ b/tests/utils.sh
@@ -0,0 +1,50 @@
+function install_executable(){
+    for i in $( ldd $* | grep -v dynamic | cut -d " " -f 3 | sed 's/://' | sort | uniq )
+    do
+        cp -f --parents $i $JUJU_HOME
+    done
+
+    # ARCH amd64
+    if [ -f /lib64/ld-linux-x86-64.so.2 ]; then
+       cp -f --parents /lib64/ld-linux-x86-64.so.2 $JUJU_HOME
+    fi
+
+    # ARCH i386
+    if [ -f  /lib/ld-linux.so.2 ]; then
+       cp -f --parents /lib/ld-linux.so.2 $JUJU_HOME
+    fi
+
+    cp -f --parents $* $JUJU_HOME/
+}
+
+function install_package(){
+    # Copy the directories
+    pacman -Ql $1 | grep "/$" | sed 's/.* //' | xargs -I {} mkdir -p $JUJU_HOME/{}
+
+    # Copy the files
+    pacman -Ql $1 | grep -v "/$" | sed 's/.* //' | xargs -I {} cp -f --parents {} $JUJU_HOME
+
+    # Copy the dynamic libraries of the executables
+    #export -f install_executable
+    #export JUJU_HOME
+    #pacman -Ql $1 | grep -v "/$" | sed 's/.* //' | grep "^/usr/bin/" | xargs -I {} bash -ic "install_executable {}"
+}
+
+function install_mini_juju(){
+    install_package filesystem 2> /dev/null
+    install_package arch-install-scripts
+    install_package bash
+    install_package proot
+    install_package coreutils
+    install_executable /usr/bin/bash
+    install_executable /usr/bin/ls
+    install_executable /usr/bin/mkdir
+    install_executable /usr/bin/proot
+}
+
+
+function is_equal(){
+    [ "$1" == "$2" ] || return 1 && return 0
+}
+
+