diff --git a/startup b/startup
index e4561de..abc153a 100644
--- a/startup
+++ b/startup
@@ -1,6 +1,6 @@
 local bootOptions = {
   { prompt = 'Default Shell', file = '/sys/boot/default.boot' },
-  { prompt = 'Opus'         , file = '/sys/boot/multishell.boot' },
+  { prompt = 'Opus'         , file = '/sys/boot/opus.boot' },
 --  { prompt = 'TLCO'         , file = '/sys/boot/tlco.boot' },
 }
 local bootOption = 2
diff --git a/sys/apis/injector.lua b/sys/apis/injector.lua
index 12c92ad..83f19aa 100644
--- a/sys/apis/injector.lua
+++ b/sys/apis/injector.lua
@@ -1,4 +1,4 @@
-local DEFAULT_UPATH = 'https://raw.githubusercontent.com/kepler155c/opus/develop/sys/apis'
+local DEFAULT_UPATH = 'https://raw.githubusercontent.com/kepler155c/opus/develop-1.8/sys/apis'
 local PASTEBIN_URL  = 'http://pastebin.com/raw'
 local GIT_URL       = 'https://raw.githubusercontent.com'
 
diff --git a/sys/apis/ui.lua b/sys/apis/ui.lua
index f12ec8b..e2815a7 100644
--- a/sys/apis/ui.lua
+++ b/sys/apis/ui.lua
@@ -125,9 +125,9 @@ function Manager:init()
           focused = true })
 
       elseif ch and self.currentPage then
-        if not self.currentPage.parent.device.side then
+        --if not self.currentPage.parent.device.side then
           self:click(ch, button, x, y)
-        end
+        --end
       end
     end,
 
diff --git a/sys/apis/util.lua b/sys/apis/util.lua
index ee5e926..251a6b6 100644
--- a/sys/apis/util.lua
+++ b/sys/apis/util.lua
@@ -412,9 +412,9 @@ function Util.httpGet(url, headers)
 end
 
 function Util.download(url, filename)
-  local contents = Util.httpGet(url)
+  local contents, msg = Util.httpGet(url)
   if not contents then
-    error('Failed to download ' .. url)
+    error(string.format('Failed to download %s\n%s', url, msg))
   end
 
   if filename then
@@ -441,6 +441,7 @@ function Util.runUrl(env, url, ...)   -- os.run equivalent
 end
 
 function Util.run(env, path, ...)
+  if type(env) ~= 'table' then error('Util.run: env must be a table', 2) end
   setmetatable(env, { __index = _G })
   local fn, m = loadfile(path, env)
   if fn then
diff --git a/sys/apps/Lua.lua b/sys/apps/Lua.lua
index 073657b..3fb6fec 100644
--- a/sys/apps/Lua.lua
+++ b/sys/apps/Lua.lua
@@ -17,7 +17,9 @@ sandboxEnv.exit = function() Event.exitPullEvents() end
 sandboxEnv._echo = function( ... ) return { ... } end
 injector(sandboxEnv)
 
-multishell.setTitle(multishell.getCurrent(), 'Lua')
+if multishell and multishell.setTitle then
+  multishell.setTitle(multishell.getCurrent(), 'Lua')
+end
 UI:configure('Lua', ...)
 
 local command = ''
@@ -143,9 +145,6 @@ function page:eventHandler(event)
     self.prompt:updateCursor()
 
   elseif event.type == 'device' then
-    if not _G.device then
-      sandboxEnv.device = Peripheral.getList()
-    end
     self:setPrompt('device', true)
     self:executeStatement('device')
 
diff --git a/sys/apps/Tabs.lua b/sys/apps/Tabs.lua
index b0de4c4..3740105 100644
--- a/sys/apps/Tabs.lua
+++ b/sys/apps/Tabs.lua
@@ -6,8 +6,8 @@ local Util  = require('util')
 
 local multishell = _ENV.multishell
 
-multishell.setTitle(multishell.getCurrent(), 'Tabs')
-UI:configure('Tabs', ...)
+multishell.setTitle(multishell.getCurrent(), 'Tasks')
+UI:configure('Tasks', ...)
 
 local page = UI.Page {
   menuBar = UI.MenuBar {
@@ -19,7 +19,7 @@ local page = UI.Page {
   grid = UI.ScrollingGrid {
     y = 2,
     columns = {
-      { heading = 'ID',     key = 'tabId',    width = 4 },
+      { heading = 'ID',     key = 'uid',      width = 4 },
       { heading = 'Title',  key = 'title'     },
       { heading = 'Status', key = 'status'    },
       { heading = 'Time',   key = 'timestamp' },
@@ -39,9 +39,9 @@ function page:eventHandler(event)
   local t = self.grid:getSelected()
   if t then
     if event.type == 'activate' or event.type == 'grid_select' then
-      multishell.setFocus(t.tabId)
+      multishell.setFocus(t.uid)
     elseif event.type == 'terminate' then
-      multishell.terminate(t.tabId)
+      multishell.terminate(t.uid)
     end
   end
   if event.type == 'quit' then
diff --git a/sys/apps/multishell b/sys/apps/multishell
index e09ec09..b702aaa 100644
--- a/sys/apps/multishell
+++ b/sys/apps/multishell
@@ -1,8 +1,3 @@
-local sandboxEnv = { }
-for k,v in pairs(_ENV) do
-  sandboxEnv[k] = v
-end
-
 _G.requireInjector()
 
 local Config = require('config')
@@ -11,7 +6,6 @@ local Util   = require('util')
 local colors     = _G.colors
 local fs         = _G.fs
 local kernel     = _G.kernel
-local keyboard   = _G.device.keyboard
 local keys       = _G.keys
 local multishell = _ENV.multishell
 local os         = _G.os
@@ -22,34 +16,15 @@ local window     = _G.window
 
 local parentTerm = term.current()
 local w,h = parentTerm.getSize()
-local tabs = { }
-local currentTab
-local _tabId = 0
 local overviewId
-local runningTab
 local tabsDirty = false
-local closeInd = '*'
-local downState = { }
+local closeInd = Util.getVersion() >= 1.76 and '\215' or '*'
 
-multishell.term = term.current()
+multishell.term = term.current() --deprecated
 
--- Default label
-if not os.getComputerLabel() then
-  local id = os.getComputerID()
-  if _G.turtle then
-    os.setComputerLabel('turtle_' .. id)
-  elseif _G.pocket then
-    os.setComputerLabel('pocket_' .. id)
-  elseif _G.commands then
-    os.setComputerLabel('command_' .. id)
-  else
-    os.setComputerLabel('computer_' .. id)
-  end
-end
-
-if Util.getVersion() >= 1.76 then
-  closeInd = '\215'
-end
+-- redirect kernel output to a window
+kernel.window = window.create(parentTerm, 1, 2, w, h - 1, false)
+kernel.terminal = kernel.window
 
 local config = {
   standard = {
@@ -71,10 +46,7 @@ local config = {
 }
 Config.load('multishell', config)
 
-local _colors = config.standard
-if parentTerm.isColor() then
-  _colors = config.color
-end
+local _colors = parentTerm.isColor() and config.color or config.standard
 
 local function redrawMenu()
   if not tabsDirty then
@@ -83,85 +55,73 @@ local function redrawMenu()
   end
 end
 
-local function resumeTab(tab, event, eventData)
-  if not tab or coroutine.status(tab.co) == 'dead' then
-    return
-  end
+function multishell.getFocus()
+  local currentTab = kernel.routines[1]
+  return currentTab.uid
+end
 
-  if not tab.filter or tab.filter == event or event == "terminate" then
-    eventData = eventData or { }
-    term.redirect(tab.terminal)
-    local previousTab = runningTab
-    runningTab = tab
-    local ok, result = coroutine.resume(tab.co, event, unpack(eventData))
-    tab.terminal = term.current()
-    if ok then
-      tab.filter = result
-    else
-      printError(result)
+function multishell.setFocus(tabId)
+  return kernel.raise(tabId)
+end
+
+function multishell.getTitle(tabId)
+  local tab = kernel.find(tabId)
+  return tab and tab.title
+end
+
+function multishell.setTitle(tabId, title)
+  local tab = kernel.find(tabId)
+  if tab then
+    if not tab.isOverview then
+      tab.title = title or ''
     end
-
-    runningTab = previousTab
-
-    return ok, result
+    redrawMenu()
   end
 end
 
-local function selectTab(tab)
-  if not tab then
-    for _,ftab in pairs(tabs) do
-      if not ftab.hidden then
-        tab = ftab
-        break
-      end
-    end
-  end
-
-  if not tab then
-    tab = tabs[overviewId]
-  end
-
-  if currentTab and currentTab ~= tab then
-    currentTab.window.setVisible(false)
-    --if coroutine.status(currentTab.co) == 'suspended' then
-      -- the process that opens a new tab won't get the lose focus event
-      -- os.queueEvent('multishell_notifyfocus', currentTab.tabId)
-      --resumeTab(currentTab, 'multishell_losefocus')
-    --end
-    if tab and not currentTab.hidden then
-      tab.previousTabId = currentTab.tabId
-    end
-  end
-
-  if tab ~= currentTab then
-    currentTab = tab
-    tab.window.setVisible(true)
-    Util.clear(keyboard.state)  --- reset keyboard state
-    -- why not just queue event with tab ID if we want to notify
-    --resumeTab(tab, 'multishell_focus')
-  end
+function multishell.getCurrent()
+  local runningTab = kernel.getCurrent()
+  return runningTab and runningTab.uid
 end
 
-local function nextTabId()
-  _tabId = _tabId + 1
-  return _tabId
+function multishell.getTab(tabId)
+  return kernel.find(tabId)
 end
 
-local function launchProcess(tab)
-  tab.tabId = nextTabId()
-  tab.timestamp = os.clock()
+function multishell.terminate(tabId)
+  os.queueEvent('multishell_terminate', tabId)
+end
+
+function multishell.getTabs()
+  return kernel.routines
+end
+
+function multishell.launch( tProgramEnv, sProgramPath, ... )
+  -- backwards compatibility
+  return multishell.openTab({
+    env = tProgramEnv,
+    path = sProgramPath,
+    args = { ... },
+  })
+end
+
+function multishell.openTab(tab)
+  if not tab.title and tab.path then
+    tab.title = fs.getName(tab.path)
+  end
+  tab.title = tab.title or 'untitled'
   tab.window = window.create(parentTerm, 1, 2, w, h - 1, false)
   tab.terminal = tab.window
-  tab.env = Util.shallowCopy(tab.env or sandboxEnv)
+
+  local routine = kernel.newRoutine(tab)
 
   tab.co = coroutine.create(function()
-
     local result, err
 
     if tab.fn then
-      result, err = Util.runFunction(tab.env, tab.fn, table.unpack(tab.args or { } ))
+      result, err = Util.runFunction(routine.env, tab.fn, table.unpack(tab.args or { } ))
     elseif tab.path then
-      result, err = Util.run(tab.env, tab.path, table.unpack(tab.args or { } ))
+      result, err = Util.run(routine.env, tab.path, table.unpack(tab.args or { } ))
     else
       err = 'multishell: invalid tab'
     end
@@ -179,119 +139,29 @@ local function launchProcess(tab)
         end
       end
     end
-    tabs[tab.tabId] = nil
-    if tab == currentTab then
-      local previousTab
-      if tab.previousTabId then
-        previousTab = tabs[tab.previousTabId]
-        if previousTab and previousTab.hidden then
-          previousTab = nil
-        end
-      end
-      selectTab(previousTab)
-    end
-    redrawMenu()
   end)
 
-  tabs[tab.tabId] = tab
-  resumeTab(tab)
-  return tab
-end
+  kernel.run(routine)
 
-function multishell.getFocus()
-  return currentTab.tabId
-end
-
-function multishell.setFocus(tabId)
-  local tab = tabs[tabId]
-  if tab then
-    selectTab(tab)
-    redrawMenu()
-    return true
-  end
-  return false
-end
-
-function multishell.getTitle(tabId)
-  local tab = tabs[tabId]
-  if tab then
-    return tab.title
-  end
-end
-
-function multishell.setTitle(tabId, title)
-  local tab = tabs[tabId]
-  if tab then
-    if not tab.isOverview then
-      tab.title = title or ''
-    end
-    redrawMenu()
-  end
-end
-
-function multishell.getCurrent()
-  if runningTab then
-    return runningTab.tabId
-  end
-end
-
-function multishell.getTab(tabId)
-  return tabs[tabId]
-end
-
-function multishell.terminate(tabId)
-  os.queueEvent('multishell_terminate', tabId)
-end
-
-function multishell.getTabs()
-  return tabs
-end
-
-function multishell.launch( tProgramEnv, sProgramPath, ... )
-  -- backwards compatibility
-  return multishell.openTab({
-    env = tProgramEnv,
-    path = sProgramPath,
-    args = { ... },
-  })
-end
-
-function multishell.openTab(tab)
-  if not tab.title and tab.path then
-    tab.title = fs.getName(tab.path)
-  end
-  tab.title = tab.title or 'untitled'
-
-  local previousTerm = term.current()
-  launchProcess(tab)
-  term.redirect(previousTerm)
-
-  if tab.hidden then
-    if coroutine.status(tab.co) == 'dead' or tab.isDead then
-      tab.hidden = false
-    end
-  elseif tab.focused then
-    multishell.setFocus(tab.tabId)
+  if tab.focused then
+    multishell.setFocus(tab.uid)
   else
     redrawMenu()
   end
 
-  return tab.tabId
+  return tab.uid
 end
 
 function multishell.hideTab(tabId)
-  local tab = tabs[tabId]
+  local tab = kernel.find(tabId)
   if tab then
     tab.hidden = true
-    if currentTab.tabId == tabId then
-      selectTab(tabs[currentTab.previousTabId])
-    end
     redrawMenu()
   end
 end
 
 function multishell.unhideTab(tabId)
-  local tab = tabs[tabId]
+  local tab = kernel.find(tabId)
   if tab then
     tab.hidden = false
     redrawMenu()
@@ -299,16 +169,34 @@ function multishell.unhideTab(tabId)
 end
 
 function multishell.getCount()
-  return Util.size(tabs)
+  return #kernel.routines
 end
 
-kernel.hook('multishell_terminate', function(_, eventData)
-  local tabId = eventData[1] or -1
-  local tab = tabs[tabId]
+kernel.hook('kernel_focus', function(_, eventData)
+  local previous = eventData[2]
+  if previous then
+    local routine = kernel.find(previous)
+    if routine and routine.window then
+      routine.window.setVisible(false)
+      if routine.hidden then
+        kernel.lower(previous)
+      end
+    end
+  end
 
+  local focused = kernel.find(eventData[1])
+  if focused and focused.window then
+    focused.window.setVisible(true)
+  end
+
+  redrawMenu()
+end)
+
+kernel.hook('multishell_terminate', function(_, eventData)
+  local tab = kernel.find(eventData[1])
   if tab and not tab.isOverview then
     if coroutine.status(tab.co) ~= 'dead' then
-      resumeTab(tab, "terminate")
+      tab:resume("terminate")
     end
   end
   return true
@@ -330,10 +218,12 @@ kernel.hook('multishell_redraw', function()
   parentTerm.clearLine()
 
   local function compareTab(a, b)
-    return a.tabId < b.tabId
+    return a.uid < b.uid
   end
 
-  for _,tab in pairs(tabs) do
+  local currentTab = kernel.routines[1]
+
+  for _,tab in pairs(kernel.routines) do
     if tab.hidden and tab ~= currentTab then
       tab.width = 0
     else
@@ -343,18 +233,18 @@ kernel.hook('multishell_redraw', function()
 
   local function width()
     local tw = 0
-    Util.each(tabs, function(t) tw = tw + t.width end)
+    Util.each(kernel.routines, function(t) tw = tw + t.width end)
     return tw
   end
 
   while width() > w - 3 do
     local tab = select(2,
-      Util.spairs(tabs, function(a, b) return a.width > b.width end)())
+      Util.spairs(kernel.routines, function(a, b) return a.width > b.width end)())
     tab.width = tab.width - 1
   end
 
   local tabX = 0
-  for _,tab in Util.spairs(tabs, compareTab) do
+  for _,tab in Util.spairs(kernel.routines, compareTab) do
     if tab.width > 0 then
       tab.sx = tabX + 1
       tab.ex = tabX + tab.width
@@ -375,7 +265,7 @@ kernel.hook('multishell_redraw', function()
     end
   end
 
-  if currentTab then
+  if currentTab and currentTab.window then
     currentTab.window.restoreCursor()
   end
 
@@ -388,8 +278,8 @@ kernel.hook('term_resize', function(_, eventData)
 
     local windowHeight = h-1
 
-    for _,key in pairs(Util.keys(tabs)) do
-      local tab = tabs[key]
+    for _,key in pairs(Util.keys(kernel.routines)) do
+      local tab = kernel.routines[key]
       local x,y = tab.window.getCursorPos()
       if y > windowHeight then
         tab.window.scroll(y - windowHeight)
@@ -402,69 +292,41 @@ kernel.hook('term_resize', function(_, eventData)
   end
 end)
 
---[[
-kernel.hook('key_up', function(_, eventData)
-  local code = eventData[1]
-  if not keyboard.state[code] then
-    return true
-  end
-end)
-]]
-
 kernel.hook('mouse_click', function(_, eventData)
   local x, y = eventData[2], eventData[3]
+  local currentTab = kernel.routines[1]
+
   if y == 1 then
     if x == 1 then
       multishell.setFocus(overviewId)
     elseif x == w then
       if currentTab then
-        multishell.terminate(currentTab.tabId)
+        multishell.terminate(currentTab.uid)
       end
     else
-      for _,tab in pairs(tabs) do
+      for _,tab in pairs(kernel.routines) do
         if not tab.hidden and tab.sx then
           if x >= tab.sx and x <= tab.ex then
-            multishell.setFocus(tab.tabId)
+            multishell.setFocus(tab.uid)
             break
           end
         end
       end
     end
-    downState.mouse = nil
     return true
   end
-  downState.mouse = currentTab
   eventData[3] = eventData[3] - 1
 end)
 
-kernel.hook({ 'mouse_up', 'mouse_drag' }, function(event, eventData)
-  if downState.mouse ~= currentTab then
-    -- don't send mouse up as the mouse click event was on another window
-    if event == 'mouse_up' then
-      downState.mouse = nil
-    end
-
-    return true -- stop propagation
-  end
+kernel.hook({ 'mouse_up', 'mouse_drag' }, function(_, eventData)
   eventData[3] = eventData[3] - 1
 end)
 
 kernel.hook('mouse_scroll', function(_, eventData)
-  local dir, y = eventData[1], eventData[3]
-
-  if y == 1 then
+  if eventData[3] == 1 then
     return true
   end
-
-  if currentTab.terminal.scrollUp then
-    if dir == -1 then
-      currentTab.terminal.scrollUp()
-    else
-      currentTab.terminal.scrollDown()
-    end
-  end
-
-  eventData[3] = y - 1
+  eventData[3] = eventData[3] - 1
 end)
 
 local function startup()
@@ -518,44 +380,10 @@ overviewId = multishell.openTab({
   path = 'sys/apps/Overview.lua',
   isOverview = true,
 })
-tabs[overviewId].title = '+'
+kernel.find(overviewId).title = '+'
 
 multishell.openTab({
   focused = true,
   fn = startup,
   title = 'Autorun',
 })
-
-local currentTabEvents = Util.transpose {
-  'char', 'key', 'key_up',
-  'mouse_click', 'mouse_drag', 'mouse_scroll', 'mouse_up',
-  'paste', 'terminate',
-}
-
-while true do
-  local tEventData = { os.pullEventRaw() }
-  local sEvent = table.remove(tEventData, 1)
-  local stopPropagation
-
-  local eventHooks = kernel.hooks[sEvent]
-  if eventHooks then
-    for i = #eventHooks, 1, -1 do
-      stopPropagation = eventHooks[i](sEvent, tEventData)
-      if stopPropagation then
-        break
-      end
-    end
-  end
-
-  if not stopPropagation then
-    if currentTabEvents[sEvent] then
-      resumeTab(currentTab, sEvent, tEventData)
-
-    else
-      -- Passthrough to all processes
-      for _,key in pairs(Util.keys(tabs)) do
-        resumeTab(tabs[key], sEvent, tEventData)
-      end
-    end
-  end
-end
diff --git a/sys/apps/shell b/sys/apps/shell
index 8871493..6da9069 100644
--- a/sys/apps/shell
+++ b/sys/apps/shell
@@ -330,7 +330,7 @@ end
 local tArgs = { ... }
 if #tArgs > 0 then
   local env = setmetatable(Util.shallowCopy(sandboxEnv), { __index = _G })
-  return run(env, ...)
+  return run(_ENV, ...)                   -- maybe _ENV
 end
 
 local Config  = require('config')
diff --git a/sys/autorun/hotkeys.lua b/sys/autorun/hotkeys.lua
index 50ffb65..b6e32d9 100644
--- a/sys/autorun/hotkeys.lua
+++ b/sys/autorun/hotkeys.lua
@@ -2,6 +2,7 @@ _G.requireInjector()
 
 local Util = require('util')
 
+local kernel     = _G.kernel
 local keyboard   = _G.device.keyboard
 local multishell = _ENV.multishell
 
@@ -16,11 +17,10 @@ end)
 
 -- restart tab
 keyboard.addHotkey('control-backspace', function()
-  local tabs = multishell.getTabs()
-  local tabId = multishell.getFocus()
-  local tab = tabs[tabId]
+  local uid = multishell.getFocus()
+  local tab = kernel.find(uid)
   if not tab.isOverview then
-    multishell.terminate(tabId)
+    multishell.terminate(uid)
     tab = Util.shallowCopy(tab)
     tab.isDead = false
     tab.focused = true
@@ -35,7 +35,7 @@ keyboard.addHotkey('control-tab', function()
   local currentTabId = multishell.getFocus()
 
   local function compareTab(a, b)
-    return a.tabId < b.tabId
+    return a.uid < b.uid
   end
   for _,tab in Util.spairs(tabs, compareTab) do
     if not tab.hidden then
@@ -44,14 +44,14 @@ keyboard.addHotkey('control-tab', function()
   end
 
   for k,tab in ipairs(visibleTabs) do
-    if tab.tabId == currentTabId then
+    if tab.uid == currentTabId then
       if k < #visibleTabs then
-        multishell.setFocus(visibleTabs[k + 1].tabId)
+        multishell.setFocus(visibleTabs[k + 1].uid)
         return
       end
     end
   end
   if #visibleTabs > 0 then
-    multishell.setFocus(visibleTabs[1].tabId)
+    multishell.setFocus(visibleTabs[1].uid)
   end
 end)
diff --git a/sys/boot/multishell.boot b/sys/boot/opus.boot
similarity index 52%
rename from sys/boot/multishell.boot
rename to sys/boot/opus.boot
index 9cf0e7e..3ccd0fe 100644
--- a/sys/boot/multishell.boot
+++ b/sys/boot/opus.boot
@@ -2,6 +2,8 @@
 local colors = _G.colors
 local fs     = _G.fs
 local http   = _G.http
+local os     = _G.os
+local shell  = _ENV.shell
 local term   = _G.term
 
 local w, h = term.getSize()
@@ -32,7 +34,7 @@ term.setCursorPos((w - 18) / 2, h)
 term.write('Loading Opus...')
 term.setCursorPos(w, h)
 
-local GIT_REPO = 'kepler155c/opus/develop'
+local GIT_REPO = 'kepler155c/opus/develop-1.8'
 local BASE     = 'https://raw.githubusercontent.com/' .. GIT_REPO
 
 local sandboxEnv = setmetatable({ }, { __index = _G })
@@ -53,7 +55,10 @@ end
 local function run(file, ...)
   local s, m = loadfile(file, makeEnv())
   if s then
-    return s(...)
+    s, m = pcall(s, ...)
+    if s then
+      return m
+    end
   end
   error('Error loading ' .. file .. '\n' .. m)
 end
@@ -80,13 +85,70 @@ if fs.exists('sys/apis/injector.lua') then
 else
   -- not local, run the file system directly from git
   _G.requireInjector = runUrl('/sys/apis/injector.lua')
-  runUrl('/sys/extensions/vfs.lua')
+  runUrl('sys/extensions/vfs.lua')
 
   -- install file system
   fs.mount('', 'gitfs', GIT_REPO)
 end
 
-run('sys/kernel.lua')
+_G.requireInjector()
+local Util = require('util')
+
+-- Default label
+if not os.getComputerLabel() then
+  local id = os.getComputerID()
+  if _G.turtle then
+    os.setComputerLabel('turtle_' .. id)
+  elseif _G.pocket then
+    os.setComputerLabel('pocket_' .. id)
+  elseif _G.commands then
+    os.setComputerLabel('command_' .. id)
+  else
+    os.setComputerLabel('computer_' .. id)
+  end
+end
+
+-- user environment
+if not fs.exists('usr/apps') then
+  fs.makeDir('usr/apps')
+end
+if not fs.exists('usr/autorun') then
+  fs.makeDir('usr/autorun')
+end
+if not fs.exists('usr/etc/fstab') then
+  Util.writeFile('usr/etc/fstab', 'usr gitfs kepler155c/opus-apps/develop-1.8')
+end
+if not fs.exists('usr/config/shell') then
+  Util.writeTable('usr/config/shell', {
+    aliases  = shell.aliases(),
+    path     = 'usr/apps:sys/apps:' .. shell.path(),
+    lua_path = '/sys/apis:/usr/apis',
+  })
+end
+
+-- shell environment
+local config = Util.readTable('usr/config/shell')
+if config.aliases then
+  for k in pairs(shell.aliases()) do
+    shell.clearAlias(k)
+  end
+  for k,v in pairs(config.aliases) do
+    shell.setAlias(k, v)
+  end
+end
+shell.setPath(config.path)
+sandboxEnv.LUA_PATH = config.lua_path
+
+Util.run(makeEnv(), 'sys/kernel.lua')
+
+-- extensions
+local dir = 'sys/extensions'
+for _,file in ipairs(fs.list(dir)) do
+  local s, m = Util.run(makeEnv(), 'sys/apps/shell', fs.combine(dir, file))
+  if not s then
+    error(m)
+  end
+end
 
 -- install user file systems
 fs.loadTab('usr/etc/fstab')
@@ -97,7 +159,25 @@ if args[1] then
   term.clear()
   term.setCursorPos(1, 1)
 end
+
+local cterm = term.current()
+
 args[1] = args[1] or 'sys/apps/multishell'
-run('sys/apps/shell', table.unpack(args))
+local routine = kernel.newRoutine({
+  path = 'sys/apps/shell',
+  args = args
+  })
+kernel.run(routine)
+local s, m = pcall(kernel.start)
+
+term.redirect(cterm)
+term.setBackgroundColor(colors.black)
+term.setTextColor(colors.white)
+term.clear()
+term.setCursorPos(1, 1)
+if not s then
+  print('\nCrash detected\n')
+  _G.printError(m)
+end
 
 fs.restore()
diff --git a/sys/etc/app.db b/sys/etc/app.db
index 00b6b27..f96b432 100644
--- a/sys/etc/app.db
+++ b/sys/etc/app.db
@@ -165,7 +165,7 @@
     run = "Events.lua",
   },
   [ "2a4d562b1d9a9c90bdede6fac8ce4f7402462b86" ] = {
-    title = "Tabs",
+    title = "Tasks",
     category = "System",
     icon = "\0307 \0303\0317__\0307\031   \
 \0303     \
diff --git a/sys/extensions/device.lua b/sys/extensions/device.lua
index d1c7f3f..28db335 100644
--- a/sys/extensions/device.lua
+++ b/sys/extensions/device.lua
@@ -30,6 +30,7 @@ local Util       = require('util')
 local device   = _G.device
 local kernel   = _G.kernel
 local keyboard = _G.device.keyboard
+local mouse    = _G.device.mouse
 local os       = _G.os
 
 kernel.hook('peripheral', function(_, eventData)
@@ -74,6 +75,23 @@ kernel.hook({ 'key', 'key_up', 'char', 'paste' }, function(event, eventData)
   end
 end)
 
+kernel.hook({ 'mouse_click', 'mouse_up', 'mouse_drag' }, function(event, eventData)
+  local button = eventData[1]
+  if event == 'mouse_click' then
+    mouse.state[button] = true
+  else
+    if not mouse.state[button] then
+      return true -- ensure mouse ups are only generated if a mouse down was sent
+    end
+    mouse.state[button] = nil
+  end
+end)
+
+kernel.hook('kernel_focus', function()
+  Util.clear(keyboard.state)
+  Util.clear(mouse.state)
+end)
+
 function keyboard.addHotkey(code, fn)
   keyboard.hotkeys[code] = fn
 end
diff --git a/sys/extensions/network.lua b/sys/extensions/network.lua
index d6fce09..450be0b 100644
--- a/sys/extensions/network.lua
+++ b/sys/extensions/network.lua
@@ -1,16 +1,13 @@
 local kernel     = _G.kernel
-local multishell = _ENV.multishell
 
 _G.network = { }
 
 kernel.hook('device_attach', function(_, eventData)
   if eventData[1] == 'wireless_modem' then
-    local s, m = multishell.openTab({
+	  local routine = kernel.newRoutine({
       path = 'sys/services/network.lua',
       hidden = true
     })
-    if not s and m then
-      debug(m)
-    end
+    kernel.run(routine)
   end
 end)
diff --git a/sys/extensions/vfs.lua b/sys/extensions/vfs.lua
index 5283403..8a29213 100644
--- a/sys/extensions/vfs.lua
+++ b/sys/extensions/vfs.lua
@@ -295,8 +295,9 @@ function fs.loadTab(path)
           fs.mount(table.unpack(Util.matches(l)))
         end)
         if not s then
-          printError('Mount failed')
-          printError(l)
+          _G.printError('Mount failed')
+          _G.printError(l)
+          _G.printError(m)
         end
       end
     end
diff --git a/sys/kernel.lua b/sys/kernel.lua
index e97a3d2..8b7f1ed 100644
--- a/sys/kernel.lua
+++ b/sys/kernel.lua
@@ -1,4 +1,4 @@
-local sandboxEnv = setmetatable({ }, { __index = _G })
+local sandboxEnv = { }
 for k,v in pairs(_ENV) do
   sandboxEnv[k] = v
 end
@@ -8,43 +8,21 @@ _G.requireInjector()
 local Util = require('util')
 
 _G.kernel = {
-  hooks = { }
+  UID = 0,
+  hooks = { },
+  routines = { },
+  terminal = _G.term.current(),
 }
 
 local kernel = _G.kernel
-local fs     = _G.fs
-local shell  = _ENV.shell
+local os     = _G.os
+local term   = _G.term
 
--- user environment
-if not fs.exists('usr/apps') then
-  fs.makeDir('usr/apps')
-end
-if not fs.exists('usr/autorun') then
-  fs.makeDir('usr/autorun')
-end
-if not fs.exists('usr/etc/fstab') then
-  Util.writeFile('usr/etc/fstab', 'usr gitfs kepler155c/opus-apps/develop')
-end
-if not fs.exists('usr/config/shell') then
-  Util.writeTable('usr/config/shell', {
-    aliases  = shell.aliases(),
-    path     = 'usr/apps:sys/apps:' .. shell.path(),
-    lua_path = '/sys/apis:/usr/apis',
-  })
-end
-
--- shell environment
-local config = Util.readTable('usr/config/shell')
-if config.aliases then
-  for k in pairs(shell.aliases()) do
-    shell.clearAlias(k)
-  end
-  for k,v in pairs(config.aliases) do
-    shell.setAlias(k, v)
-  end
-end
-shell.setPath(config.path)
-_G.LUA_PATH = config.lua_path
+local focusedRoutineEvents = Util.transpose {
+  'char', 'key', 'key_up',
+  'mouse_click', 'mouse_drag', 'mouse_scroll', 'mouse_up',
+  'paste', 'terminate',
+}
 
 -- any function that runs in a kernel hook does not run in
 -- a separate coroutine or have a window. an error in a hook
@@ -73,11 +51,158 @@ function kernel.unhook(event, fn)
   end
 end
 
--- extensions
-local dir = 'sys/extensions'
-for _,file in ipairs(fs.list(dir)) do
-  local s, m = Util.run(sandboxEnv, 'sys/apps/shell', fs.combine(dir, file))
-  if not s then
-    error(m)
+local Routine = { }
+
+function Routine:resume(event, ...)
+  if not self.co or coroutine.status(self.co) == 'dead' then
+    return
+  end
+
+  if not self.filter or self.filter == event or event == "terminate" then
+    term.redirect(self.terminal)
+
+    local previous = kernel.running
+    kernel.running = self -- stupid shell set title
+    local ok, result = coroutine.resume(self.co, event, ...)
+    kernel.running = previous
+
+    self.terminal = term.current()
+    if ok then
+      self.filter = result
+    else
+      _G.printError(result)
+    end
+    if coroutine.status(self.co) == 'dead' then
+      Util.removeByValue(kernel.routines, self)
+      if #kernel.routines > 0 then
+        os.queueEvent('kernel_focus', kernel.routines[1].uid)
+      end
+    end
+    return ok, result
   end
 end
+
+function kernel.getFocused()
+  return kernel.routines[1]
+end
+
+function kernel.getCurrent()
+  return kernel.running
+end
+
+function kernel.newRoutine(args)
+  kernel.UID = kernel.UID + 1
+
+  args = args or { }
+
+  local routine = setmetatable(args, { __index = Routine })
+  routine.uid = kernel.UID
+
+  return routine
+end
+
+function kernel.run(routine)
+  routine.timestamp = os.clock()
+  routine.terminal = routine.terminal or kernel.terminal
+  routine.window = routine.window or kernel.window
+  routine.env = Util.shallowCopy(routine.env or sandboxEnv)
+
+  routine.co = routine.co or coroutine.create(function()
+    local result, err
+
+    if routine.fn then
+      result, err = Util.runFunction(routine.env, routine.fn, table.unpack(routine.args or { } ))
+    elseif routine.path then
+      result, err = Util.run(routine.env, routine.path, table.unpack(routine.args or { } ))
+    else
+      err = 'kernel: invalid routine'
+    end
+
+    if not result and err and err ~= 'Terminated' then
+      _G.printError(tostring(err))
+    end
+  end)
+
+  table.insert(kernel.routines, routine)
+
+  local previousTerm = term.current()
+  local s, m = routine:resume()
+  term.redirect(previousTerm)
+
+  return s, m
+end
+
+function kernel.raise(uid)
+  local routine = Util.find(kernel.routines, 'uid', uid)
+
+  if routine then
+    local previous = kernel.routines[1]
+    if routine ~= previous then
+      Util.removeByValue(kernel.routines, routine)
+      table.insert(kernel.routines, 1, routine)
+    end
+    os.queueEvent('kernel_focus', routine.uid, previous and previous.uid)
+    return true
+  end
+  return false
+end
+
+function kernel.lower(uid)
+  local routine = Util.find(kernel.routines, 'uid', uid)
+
+  if routine and #kernel.routines > 1 then
+    Util.removeByValue(kernel.routines, routine)
+    table.insert(kernel.routines, routine)
+    return true
+  end
+  return false
+end
+
+function kernel.find(uid)
+  return Util.find(kernel.routines, 'uid', uid)
+end
+
+function kernel.halt()
+  os.queueEvent('kernel_halt')
+end
+
+function kernel.event(event, eventData)
+  local stopPropagation
+
+  local eventHooks = kernel.hooks[event]
+  if eventHooks then
+    for i = #eventHooks, 1, -1 do
+      local s, m = pcall(function()
+        stopPropagation = eventHooks[i](event, eventData)
+      end)
+      if not s then
+        error(m)
+      end
+      if stopPropagation then
+        break
+      end
+    end
+  end
+
+  if not stopPropagation then
+    if focusedRoutineEvents[event] then
+      local active = kernel.routines[1]
+      if active then
+        active:resume(event, table.unpack(eventData))
+      end
+    else
+      -- Passthrough to all processes
+      for _,routine in pairs(Util.shallowCopy(kernel.routines)) do
+        routine:resume(event, table.unpack(eventData))
+      end
+    end
+  end
+end
+
+function kernel.start()
+  repeat
+    local eventData = { os.pullEventRaw() }
+    local event = table.remove(eventData, 1)
+    kernel.event(event, eventData)
+  until event == 'kernel_halt' or not kernel.routines[1]
+end
diff --git a/sys/services/gpshost.lua b/sys/services/gpshost.lua
index c4380f9..c06f4be 100644
--- a/sys/services/gpshost.lua
+++ b/sys/services/gpshost.lua
@@ -1,4 +1,4 @@
-if device.wireless_modem then
+if _G.device.wireless_modem then
 
   _G.requireInjector()
   local Config = require('config')
@@ -7,11 +7,8 @@ if device.wireless_modem then
   Config.load('gps', config)
 
   if config.host and type(config.host) == 'table' then
-
-    multishell.setTitle(multishell.getCurrent(), 'GPS Daemon')
-
-    os.run(getfenv(1), '/rom/programs/gps', 'host', config.host.x, config.host.y, config.host.z)
-
+    _ENV._APP_TITLE = 'GPS Daemon'
+    os.run(_ENV, '/rom/programs/gps', 'host', config.host.x, config.host.y, config.host.z)
     print('GPS daemon stopped')
   end
 end
diff --git a/sys/services/log.lua b/sys/services/log.lua
index 7284da6..1ba194c 100644
--- a/sys/services/log.lua
+++ b/sys/services/log.lua
@@ -3,26 +3,41 @@ _G.requireInjector()
 local Terminal = require('terminal')
 local Util     = require('util')
 
+local kernel     = _G.kernel
 local keyboard   = _G.device.keyboard
 local multishell = _ENV.multishell
 local os         = _G.os
 local term       = _G.term
 
-multishell.setTitle(multishell.getCurrent(), 'Debug')
+_ENV._APP_TITLE = 'Debug'
 
 term.redirect(Terminal.scrollable(term.current(), 50))
 
 local tabId = multishell.getCurrent()
-local terminal = term.current()
 local previousId
 
 _G.debug = function(pattern, ...)
   local oldTerm = term.current()
-  term.redirect(terminal)
+  term.redirect(kernel.terminal)
   Util.print(pattern, ...)
   term.redirect(oldTerm)
 end
 
+kernel.hook('mouse_scroll', function(_, eventData)
+  local dir, y = eventData[1], eventData[3]
+
+  if y > 1 then
+    local currentTab = kernel.routines[1]
+    if currentTab.terminal.scrollUp then
+      if dir == -1 then
+        currentTab.terminal.scrollUp()
+      else
+        currentTab.terminal.scrollDown()
+      end
+    end
+  end
+end)
+
 print('Debug started')
 print('Press ^d to activate debug window')
 
diff --git a/sys/services/network.lua b/sys/services/network.lua
index 98420b1..3f32c0b 100644
--- a/sys/services/network.lua
+++ b/sys/services/network.lua
@@ -5,7 +5,6 @@ local Util  = require('util')
 
 local device     = _G.device
 local fs         = _G.fs
-local multishell = _ENV.multishell
 local network    = _G.network
 local os         = _G.os
 local printError = _G.printError
@@ -14,7 +13,7 @@ if not device.wireless_modem then
   return
 end
 
-multishell.setTitle(multishell.getCurrent(), 'Net Daemon')
+_ENV._APP_TITLE = 'Net Daemon'
 
 print('Net daemon started')
 
diff --git a/sys/services/transort.lua b/sys/services/transort.lua
index c163509..9651504 100644
--- a/sys/services/transort.lua
+++ b/sys/services/transort.lua
@@ -6,10 +6,9 @@
   * background read buffering
 ]]--
 
-local multishell = _ENV.multishell
 local os = _G.os
 
-multishell.setTitle(multishell.getCurrent(), 'Net transport')
+_ENV._APP_TITLE = 'Net transport'
 
 local computerId = os.getComputerID()