diff --git a/inc/nux.inc.sh b/inc/nux.inc.sh
index ddf935b..4a0a9b7 100644
--- a/inc/nux.inc.sh
+++ b/inc/nux.inc.sh
@@ -2,106 +2,14 @@
 
 readonly NUX_INC_DIR=$(dirname $(realpath  ${BASH_SOURCE[0]}))
 readonly NUX_ENV_DIR=$(dirname $NUX_INC_DIR)
+readonly NUX_CACHE_DIR="$NUX_ENV_DIR/cache"
 
 # Color definitions
 
 
-if [ -t 1 ]; then
-  readonly nc_bold=`tput setaf 0`
-  readonly nc_bg_bold=`tput setab 0`
-  readonly nc_black=`tput setab 0`
-  readonly nc_bg_black=`tput setab 0`
-  readonly nc_cyan=`tput setaf 6`
-  readonly nc_bg_cyan=`tput setab 6`
-  readonly nc_magenta=`tput setaf 5`
-  readonly nc_bg_magenta=`tput setab 5`
-  readonly nc_red=`tput setaf 1`
-  readonly nc_bg_red=`tput setab 1`
-  readonly nc_white=`tput setaf 7`
-  readonly nc_bg_white=`tput setab 7`
-  readonly nc_green=`tput setaf 2`
-  readonly nc_bg_green=`tput setab 2`
-  readonly nc_yellow=`tput setaf 3`
-  readonly nc_bg_yellow=`tput setab 3`
-  readonly nc_blue=`tput setaf 4`
-  readonly nc_bg_blue=`tput setab 4`
-  readonly nc_end=`tput sgr0`
 
-  readonly NC_Bold=`tput bold`
-  readonly NC_No=`tput sgr0` # No Color
-  readonly NC_Black='\033[0;30m'
-  readonly NC_Green='\033[0;32m'
-  readonly NC_Red=$nc_bold$nc_red
-  readonly NC_BrownOrange='\033[0;33m'
-  readonly NC_Blue='\033[0;34m'
-  readonly NC_Purple='\033[0;35m'
-  readonly NC_Cyan='\033[0;36m'
-  readonly NC_LightGray='\033[0;37m'
-  readonly NC_DarkGray='\033[1;30m'
-  readonly NC_LightRed='\033[1;31m'
-  readonly NC_LightGreen='\033[1;32m'
-  readonly NC_Yellow=$nc_yellow
-  readonly NC_LightBlue='\033[1;34m'
-  readonly NC_LightPurple='\033[1;35m'
-  readonly NC_LightCyan='\033[1;36m'
-  readonly NC_White=$nc_white
-
-  readonly NC_error=$NC_Red
-fi
 ## #Public functions:
 ##
-## ##Logging
-
-# Color for message levels
-NC_LOG_color_info=$NC_LightGray
-NC_LOG_color_error=$NC_LightRed
-NC_LOG_color_warning=$NC_Yellow
-NC_LOG_color_debug=$NC_White
-
-NC_LOG_current=3
-
-NC_LOG_id_none=0
-NC_LOG_id_error=1
-NC_LOG_id_warning=2
-NC_LOG_id_info=3
-NC_LOG_id_debug=4
-NC_LOG_id_trace=5
-
-##
-## NUX Script environment provides basic logging capabilities.
-##
-## Currently there are 5 log levels supported (in order of detail):
-##   error
-##   warning
-##   info
-##   debug
-##   trace
-##
-## nux.log:: <level> <message>
-##     Outputs log message to *STDERR*. LOG messages are filtered out based on
-##     level. Use *nux.log.level* to specify which messages should be displayed.
-##
-##
-function nux.log {
-  local level=$1
-  local message=$2
-  local color=NC_LOG_color_$level
-  local level_num=NC_LOG_id_$level
-  shift;
-  if [  ${!level_num} -le $NC_LOG_current  ]; then
-    echo -e "${!color}[$level]$NC_No $*$NC_No" >&2
-  fi
-}
-
-
-## nux.log.level:: <level>
-##     Sets maximum level of details to be logged.
-##
-function  nux.log.level {
-  local level=$1
-  local level_id=NC_LOG_id_$level
-  NC_LOG_current=${!level_id}
-}
 
 function nux.echo.error {
 	echo "${NC_error}$* ${NC_No}";
@@ -139,41 +47,17 @@ function nux.require {
 
 }
 
-function nux.include {
+function nux.use {
   local incfile="$1.inc.sh"
-  source "$NUX_INC_DIR/$incfile"
-}
-
-## nux.check.function:: <name>
-##
-function nux.check.function {
-  nux.log trace "Checking if $1 is function."
-  declare -f "$1" &>/dev/null && return 0
-  return 1
-}
-
-function nux.check.nuxenv.file {
-  path=$(realpath -Lms "$1")
-  [[ "$path" =~ "^$NUX_ENV_DIR" ]]
-}
-
-
-function nux.check.optional {
-  local function="$1"; shift;
-  if nux.check.function "$function" ; then
-    $function "$@"
-  fi
-}
-
-function nux.check.exec {
-  local binary=$1;
-  test -n "$(which "$binary")"
-}
-
-## nux.check.file.exists:: <name>
-##
-function nux.check.file.exists {
-	test -e "$1" -o -h "$1";
+	local nuxshfile="$1.nuxsh.sh"
+	#FIXME: Do not use same file twice.
+	if [ -e "$NUX_INC_DIR/$incfile" ]; then
+		source "$NUX_INC_DIR/$incfile";
+	elif [ -e "$NUX_INC_DIR/$nuxshfile" ]; then
+		nux.nuxsh.use "$NUX_INC_DIR/$nuxshfile" "$NUX_CACHE_DIR/inc/$incfile";
+	else
+		nux.fatal "$1 not available."
+	fi
 }
 
 function nux.eval {
@@ -206,25 +90,8 @@ function nux.dirty.urlencode {
     echo -n "$1" | sed "s/ /%20/g"
 }
 
-function nux.help.comment {
-  local source="$1"
-  if nux.check.file.exists "$source" ; then
-    grep -E "^\#\#( |$)" "$source" \
-      | cut -d\# -f3- \
-      | cut -d" " -f2- \
-      | nux.help.shelldoc
-  fi
-}
 
-function nux.help.shelldoc {
-  sed -r \
-    -e "s/^## ?(.*)/${NC_White}\1${NC_No}/gI" \
-    -e "s/^# ?(.*)/${NC_Bold}\1${NC_No}/gI" \
-    -e "s/^([ a-z0-9.-_]*)::/${NC_Bold}\1${NC_No}/gI" \
-    -e "s/\*\*([^*]*)\*\*/${NC_Bold}\1${NC_No}/gI"  \
-    -e "s/\*([^*]*)\*/${NC_White}\1${NC_No}/gI"  \
-    --
-}
+
 
 function nux.url.parse {
   format=${2:-"protocol:\2\nuser:\4\nhost:\5\nport:\7 \npath:\8"}
@@ -232,3 +99,7 @@ function nux.url.parse {
     -re "s/(([^:\/]*):\/\/)?(([^@\/:]*)@)?([^:\/]+)(:([0-9]+))?(\/(.*))?/$format/g"
 
 }
+
+nux.use nux/log
+nux.use nux/check
+nux.use nux/nuxsh
diff --git a/inc/nux/check.inc.sh b/inc/nux/check.inc.sh
new file mode 100644
index 0000000..6432309
--- /dev/null
+++ b/inc/nux/check.inc.sh
@@ -0,0 +1,31 @@
+## nux.check.function:: <name>
+##
+function nux.check.function {
+  nux.log trace "Checking if $1 is function."
+  declare -f "$1" &>/dev/null && return 0
+  return 1
+}
+
+function nux.check.nuxenv.file {
+  path=$(realpath -Lms "$1")
+  [[ "$path" =~ "^$NUX_ENV_DIR" ]]
+}
+
+
+function nux.check.optional {
+  local function="$1"; shift;
+  if nux.check.function "$function" ; then
+    $function "$@"
+  fi
+}
+
+function nux.check.exec {
+  local binary=$1;
+  test -n "$(which "$binary")"
+}
+
+## nux.check.file.exists:: <name>
+##
+function nux.check.file.exists {
+	test -e "$1" -o -h "$1";
+}
diff --git a/inc/nux/color.nuxsh.sh b/inc/nux/color.nuxsh.sh
new file mode 100644
index 0000000..9f0cf45
--- /dev/null
+++ b/inc/nux/color.nuxsh.sh
@@ -0,0 +1,42 @@
+if [ -t 1 ] {
+  readonly nc_bold=`tput setaf 0`
+  readonly nc_bg_bold=`tput setab 0`
+  readonly nc_black=`tput setab 0`
+  readonly nc_bg_black=`tput setab 0`
+  readonly nc_cyan=`tput setaf 6`
+  readonly nc_bg_cyan=`tput setab 6`
+  readonly nc_magenta=`tput setaf 5`
+  readonly nc_bg_magenta=`tput setab 5`
+  readonly nc_red=`tput setaf 1`
+  readonly nc_bg_red=`tput setab 1`
+  readonly nc_white=`tput setaf 7`
+  readonly nc_bg_white=`tput setab 7`
+  readonly nc_green=`tput setaf 2`
+  readonly nc_bg_green=`tput setab 2`
+  readonly nc_yellow=`tput setaf 3`
+  readonly nc_bg_yellow=`tput setab 3`
+  readonly nc_blue=`tput setaf 4`
+  readonly nc_bg_blue=`tput setab 4`
+  readonly nc_end=`tput sgr0`
+
+  readonly NC_Bold=`tput bold`
+  readonly NC_No=`tput sgr0` # No Color
+  readonly NC_Black='\033[0;30m'
+  readonly NC_Green='\033[0;32m'
+  readonly NC_Red=$nc_bold$nc_red
+  readonly NC_BrownOrange='\033[0;33m'
+  readonly NC_Blue='\033[0;34m'
+  readonly NC_Purple='\033[0;35m'
+  readonly NC_Cyan='\033[0;36m'
+  readonly NC_LightGray='\033[0;37m'
+  readonly NC_DarkGray='\033[1;30m'
+  readonly NC_LightRed='\033[1;31m'
+  readonly NC_LightGreen='\033[1;32m'
+  readonly NC_Yellow=$nc_yellow
+  readonly NC_LightBlue='\033[1;34m'
+  readonly NC_LightPurple='\033[1;35m'
+  readonly NC_LightCyan='\033[1;36m'
+  readonly NC_White=$nc_white
+
+  readonly NC_error=$NC_Red
+}
diff --git a/inc/nux/help.nuxsh.sh b/inc/nux/help.nuxsh.sh
new file mode 100644
index 0000000..8bca738
--- /dev/null
+++ b/inc/nux/help.nuxsh.sh
@@ -0,0 +1,21 @@
+#!/usr/bin/env nuxsh
+@namespace nux.help. {
+  function :shelldoc {
+    sed -r \
+      -e "s/^## ?(.*)/${NC_White}\1${NC_No}/gI" \
+      -e "s/^# ?(.*)/${NC_Bold}\1${NC_No}/gI" \
+      -e "s/^([ a-z0-9.-_]*)::/${NC_Bold}\1${NC_No}/gI" \
+      -e "s/\*\*([^*]*)\*\*/${NC_Bold}\1${NC_No}/gI"  \
+      -e "s/\*([^*]*)\*/${NC_White}\1${NC_No}/gI"  \
+      --
+  }
+
+  function :comment source {
+    if nux.check.file.exists "$source" ; then
+      grep -E "^\#\#( |$)" "$source" \
+        | cut -d\# -f3- \
+        | cut -d" " -f2- \
+        | nux.help.shelldoc
+    fi
+  }
+}
diff --git a/inc/nux/log.inc.sh b/inc/nux/log.inc.sh
new file mode 100644
index 0000000..f853f4e
--- /dev/null
+++ b/inc/nux/log.inc.sh
@@ -0,0 +1,52 @@
+## ##Logging
+
+# Color for message levels
+NC_LOG_color_info=$NC_LightGray
+NC_LOG_color_error=$NC_LightRed
+NC_LOG_color_warning=$NC_Yellow
+NC_LOG_color_debug=$NC_White
+
+NC_LOG_current=3
+
+NC_LOG_id_none=0
+NC_LOG_id_error=1
+NC_LOG_id_warning=2
+NC_LOG_id_info=3
+NC_LOG_id_debug=4
+NC_LOG_id_trace=5
+
+##
+## NUX Script environment provides basic logging capabilities.
+##
+## Currently there are 5 log levels supported (in order of detail):
+##   error
+##   warning
+##   info
+##   debug
+##   trace
+##
+## nux.log:: <level> <message>
+##     Outputs log message to *STDERR*. LOG messages are filtered out based on
+##     level. Use *nux.log.level* to specify which messages should be displayed.
+##
+##
+function nux.log {
+  local level=$1
+  local message=$2
+  local color=NC_LOG_color_$level
+  local level_num=NC_LOG_id_$level
+  shift;
+  if [  ${!level_num} -le $NC_LOG_current  ]; then
+    echo -e "${!color}[$level]$NC_No $*$NC_No" >&2
+  fi
+}
+
+
+## nux.log.level:: <level>
+##     Sets maximum level of details to be logged.
+##
+function  nux.log.level {
+  local level=$1
+  local level_id=NC_LOG_id_$level
+  NC_LOG_current=${!level_id}
+}
diff --git a/inc/nuxr.nuxsh.sh b/inc/nuxr.nuxsh.sh
new file mode 100644
index 0000000..8436199
--- /dev/null
+++ b/inc/nuxr.nuxsh.sh
@@ -0,0 +1,100 @@
+
+nux.use nux/color
+nux.use nuxr/repl
+
+@prefix check nux.check.
+@prefix help nux.help.
+
+@namespace nuxr. {
+  function :run TASK {
+    if check:function task.$TASK {
+      nux.log debug  "Running task: $TASK";
+      task.$TASK "$@" # Runs task
+    else
+      echo "$NUX_SCRIPTNAME: Unrecognized task  ''$TASK' not available."
+      echo "Try '$NUX_SCRIPTNAME help' for more information."
+      return -1
+    }
+  }
+
+  function :run.subtask SUBTASK {
+    if nux.check.function task.$TASK.$SUBTASK {
+      nux.log debug  "Running subtask: $TASK";
+      task.$TASK.$SUBTASK "$@" # Runs task
+    else
+      echo "$NUX_SCRIPTNAME: '$TASK' '$SUBTASK' not available."
+      echo "Try '$NUX_SCRIPTNAME help' for more information."
+    }
+  }
+
+  function :main {
+    :run "$@"
+  }
+}
+
+@namespace nuxr.task. {
+  function :help {
+    nuxr.task.help. "$@"
+  }
+### nuxr.task.interactive::
+###   Runs an interactive taskie shell with base taskie commands available.
+###
+  function :interactive() {
+    nux.use nux.repl
+    nux.repl.start nuxr.repl.process nuxr.repl.prompt nuxr.repl.completer
+  }
+
+}
+
+@namespace nuxr.task.help. {
+
+  function : {
+    nux.use nux/help
+    allArgs="$@"
+    if [ -z "$allArgs" ] {
+      echo Usage: $NC_Bold$NUX_SCRIPTNAME ${NC_No}${NC_White}\<command\>${NC_No} [\<options\>]
+      help:comment "$NUX_SCRIPT"
+      help:comment "$NUX_RUNNER"
+      nux.exec.optional task.help.additional
+    else
+      :topic "$@"
+    }
+  }
+
+  ## nuxr.task.help.topic
+  function :topic {
+    first="$1"
+    topic="$@"
+    topic_dot=$(tr " " "." <<< $topic)
+    nux.log trace "Displaying topic for: '$topic' '$topic_dot'"
+
+    if check:function "task.help.$topic_dot" {
+      shift;
+      task.help.$topic "$@";
+    elif nux.check.function "task.help.$first" ; then
+      shift;
+      task.help.$first "$@";
+    else
+      nuxr.task.help.comment "$NUX_SCRIPT" "$topic" \
+        || nuxr.task.help.comment "$NUX_RUNNER" "$topic" \
+        || echo "Help topic $1 not found. Run '$NUX_APPNAME help'  to see topics."
+    }
+  }
+
+  function :comment script task {
+    local task_dot=$(tr " " "." <<< "$task")
+    nux.log trace "Trying to figure task documentation location for $task $task_dot"
+    doc_start=$(grep -hn -E "## +($task)::" "$script" | cut -d: -f1)
+    code_start=$(grep -hn -E "((function +task.$task_dot)|(task.$task_dot *\(\))) +{" "$script" | cut -d: -f1)
+    nux.log trace "doc_start" $doc_start $code_start
+    if [ -n "$doc_start" -a -n "$code_start" ] {
+      sed -n "$doc_start,$code_start"p "$script" \
+        | grep "^\#\#" \
+        | sed -re "s/^#+ ?(.*)/\1/gi" \
+        | nux.help.shelldoc
+        return 0
+      else
+        return -1
+      }
+    }
+}
diff --git a/inc/nuxr/repl.nuxsh.sh b/inc/nuxr/repl.nuxsh.sh
new file mode 100644
index 0000000..dfd3f1d
--- /dev/null
+++ b/inc/nuxr/repl.nuxsh.sh
@@ -0,0 +1,134 @@
+#
+###
+#
+#
+@namespace nuxr.repl. {
+  function :process {
+    backendFunc=task.$command;
+    if nux.check.function repl.command.$command; then
+      eval repl.command.$command "$arguments"
+    elif nux.check.function task.$command; then
+      eval nuxr.run "$command" "$arguments"
+    else
+      echo "$command" is not defined.
+    fi
+  }
+
+  function :expose {
+    # FIXME: Figure different way of exposing direct functions without wrapping
+    for cmd in "$@"; do
+      eval "function repl.command.$cmd { $cmd \"\$@\"; }"
+    done
+  }
+
+  function :prompt {
+    echo "${nc_green}$NUX_APPNAME${nc_end}> "
+  }
+
+}
+
+@namespace repl.command. {
+  ##
+  ##  repl.command.::
+  ##    fallback command which does nothing if user just presses enter.
+  ##
+  function : {
+    echo >>/dev/null
+  }
+
+  function :help {
+    if [ -z "$@" ]  ;then
+      echo "Usage: help [<command> | <topic>]"
+      echo Displays help for specified topic or command.
+      echo
+      echo "${nc_white}Available topics:$nc_end"
+      :search.tasks help.$current_word | cut -d"." -f2 | column
+      echo
+      echo "${nc_white}Available commands:$nc_end"
+      :search.tasks $current_word | grep -v "help\\." | column
+    else
+      nuxr.task.help.topic "$@"
+    fi
+  }
+
+}
+
+
+@namespace nuxr.repl.completer. {
+
+  function :search.tasks  {
+    set | grep -G "^task\.$1.* ()" \
+    | cut -d "." -f2- \
+    | cut -d"(" -f1
+  }
+
+
+  function :search.commands {
+    set | grep -E "^((repl\\.command)|(task))\\.$1.* ()" \
+    | sed -re 's/^((repl\.command)|(task))\.//gi' \
+    | cut -d"(" -f1 | sort | uniq
+  }
+
+  function :help() {
+      nux.log debug "Help completer"
+      nux.log debug "current_pos $current_pos"
+      nux.log debug "current word $current_word"
+      if [ $current_pos -eq 2 ]; then
+        :search.tasks $current_word | grep -v "help."
+        :search.tasks help.$current_word | cut -d"." -f2
+      fi
+    }
+
+    function :_prefix_task() {
+      nux.log debug "Prefix completer. $current_pos $current_word"
+      if [ $current_pos -eq 2 ]; then
+        :search.tasks $current_word
+      else
+        nuxr.repl.completer "${line#$command }"
+      fi
+    }
+
+    function nuxr.repl.completer {
+      local line=$1;
+      nux.log debug "Requested completion for " "'$line'"
+
+      local words=($line)
+      local current_pos="${#words[@]}";
+      local current_word="";
+      if [ "$current_pos" -gt 0 ]; then
+        current_word="${words[${#words[@]}-1]}";
+        if [ -n "$line" -a "$line" != "${line%% }" ] ; then
+          nux.log debug "Creating proposal for next word."
+          let current_pos=current_pos+1
+          current_word=""
+        fi
+      fi
+      local result="";
+      if [ $current_pos -le 1 ] ; then
+        result=$(nuxr.repl.completer.search.commands $current_word | grep -v "help\\.")
+      elif [ $current_pos -ge 2 ]; then
+        command="${words[0]}"
+        nux.log debug "Trying to use completer for '$command'"
+        case $command in
+          debug) ;&
+          trace)
+          result=$(nuxr.repl.completer._prefix_task)
+          ;;
+          *)
+          result=$(nux.exec.optional nuxr.repl.completer.$command)
+          ;;
+        esac;
+      fi
+
+      if [ -n "$result" ]; then
+        nux.log debug "Completion found."
+        echo $result
+      else
+        nux.log debug "No completion found."
+        printf '\a' >> $(tty)
+        if [ $current_pos -gt 1 ]; then
+          echo $current_word
+        fi
+      fi
+    }
+}