diff --git a/sys/apps/Sniff.lua b/sys/apps/Sniff.lua
index 5336234..41c1543 100644
--- a/sys/apps/Sniff.lua
+++ b/sys/apps/Sniff.lua
@@ -255,7 +255,7 @@ function page.packetSlide:eventHandler(event)
 		page:setFocus(page.packetGrid)
 
 	elseif event.type == 'packet_lua' then
-		multishell.openTab({ path = 'sys/apps/Lua.lua', args = { self.currentPacket.message }, focused = true })
+		multishell.openTab(_ENV, { path = 'sys/apps/Lua.lua', args = { self.currentPacket.message }, focused = true })
 
 	elseif event.type == 'prev_packet' then
 		local c = self.currentPacket
diff --git a/sys/apps/Tasks.lua b/sys/apps/Tasks.lua
index be21f9c..4e359fc 100644
--- a/sys/apps/Tasks.lua
+++ b/sys/apps/Tasks.lua
@@ -12,6 +12,7 @@ local page = UI.Page {
 		buttons = {
 			{ text = 'Activate',  event = 'activate'  },
 			{ text = 'Terminate', event = 'terminate' },
+			{ text = 'Inspect',   event = 'inspect'   },
 		},
 	},
 	grid = UI.ScrollingGrid {
@@ -49,6 +50,12 @@ local page = UI.Page {
 				multishell.setFocus(t.uid)
 			elseif event.type == 'terminate' then
 				multishell.terminate(t.uid)
+			elseif event.type == 'inspect' then
+				multishell.openTab(_ENV, {
+					path = 'sys/apps/Lua.lua',
+					args = { t },
+					focused = true,
+				})
 			end
 		end
 		if event.type == 'quit' then
diff --git a/sys/apps/inspect.lua b/sys/apps/inspect.lua
index 0df9526..90b59db 100644
--- a/sys/apps/inspect.lua
+++ b/sys/apps/inspect.lua
@@ -110,7 +110,7 @@ page = UI.Page {
 					self.grid:draw()
 
 				elseif event.type == 'grid_select' then
-					multishell.openTab({
+					multishell.openTab(_ENV, {
 						path = 'sys/apps/Lua.lua',
 						args = { event.selected.raw },
 						focused = true,
diff --git a/sys/apps/netdaemon.lua b/sys/apps/netdaemon.lua
index 1d3fd66..8ffca25 100644
--- a/sys/apps/netdaemon.lua
+++ b/sys/apps/netdaemon.lua
@@ -1,5 +1,3 @@
-_G.requireInjector(_ENV)
-
 local Event = require('opus.event')
 local Util  = require('opus.util')
 
diff --git a/sys/apps/network/snmp.lua b/sys/apps/network/snmp.lua
index 18a4143..2c48ee1 100644
--- a/sys/apps/network/snmp.lua
+++ b/sys/apps/network/snmp.lua
@@ -31,21 +31,14 @@ local function snmpConnection(socket)
 			socket:write('pong')
 
 		elseif msg.type == 'script' then
-			local env = kernel.makeEnv()
-			local fn, err = load(msg.args, 'script', nil, env)
-			if fn then
-				kernel.run({
-					fn = fn,
-					env = env,
-					title = 'script',
-				})
-			else
-				_G.printError(err)
-			end
+			kernel.run(_ENV, {
+				chunk = msg.args,
+				title = 'script',
+			})
 
 		elseif msg.type == 'scriptEx' then
 			local s, m = pcall(function()
-				local env = kernel.makeEnv()
+				local env = kernel.makeEnv(_ENV)
 				local fn, m = load(msg.args, 'script', nil, env)
 				if not fn then
 					error(m)
diff --git a/sys/apps/network/telnet.lua b/sys/apps/network/telnet.lua
index 87ab04d..ff92298 100644
--- a/sys/apps/network/telnet.lua
+++ b/sys/apps/network/telnet.lua
@@ -41,12 +41,12 @@ local function telnetHost(socket, mode)
 		end
 	end
 
-	local shellThread = kernel.run({
+	local shellThread = kernel.run(_ENV, {
 		window = win,
 		title = mode .. ' client',
 		hidden = true,
 		fn = function()
-			Util.run(kernel.makeEnv(), Alt.get('shell'), table.unpack(termInfo.program))
+			Util.run(kernel.makeEnv(_ENV), Alt.get('shell'), table.unpack(termInfo.program))
 			if socket.queue then
 				socket:write(socket.queue)
 			end
diff --git a/sys/apps/shell.lua b/sys/apps/shell.lua
index 6b23582..92cf23d 100644
--- a/sys/apps/shell.lua
+++ b/sys/apps/shell.lua
@@ -6,16 +6,6 @@ local fs         = _G.fs
 local settings   = _G.settings
 local shell      = _ENV.shell
 
-local sandboxEnv = { }
-for k,v in pairs(_ENV) do
-	sandboxEnv[k] = v
-end
-sandboxEnv.package = nil
-sandboxEnv.require = nil
-sandboxEnv.arg = nil
-sandboxEnv._ENV = nil
-sandboxEnv.shell = shell
-
 _G.requireInjector(_ENV)
 
 local trace = require('opus.trace')
@@ -51,7 +41,7 @@ local function run(...)
 	local args = tokenise(...)
 	local command = table.remove(args, 1) or error('No such program')
 	local isUrl = not not command:match("^(https?:)")
-	local env = shell.makeEnv()
+	local env = shell.makeEnv(_ENV)
 
 	local path, loadFn
 	if isUrl then
@@ -64,7 +54,7 @@ local function run(...)
 
 	local fn, err = loadFn(path, env)
 	if not fn then
-		error(err)
+		error(err, -1)
 	end
 
 	if _ENV.multishell then
@@ -287,13 +277,9 @@ function shell.getRunningInfo()
 	return tProgramStack[#tProgramStack]
 end
 
-function shell.setEnv(name, value)
-	_ENV[name] = value
-	sandboxEnv[name] = value
-end
-
-function shell.makeEnv()
-	local env = setmetatable(Util.shallowCopy(sandboxEnv), { __index = _G })
+-- convenience function for making a runnable env
+function shell.makeEnv(env)
+	env = setmetatable(Util.shallowCopy(env), { __index = _G })
 	_G.requireInjector(env)
 	return env
 end
@@ -321,7 +307,6 @@ function shell.newTab(tabInfo, ...)
 
 	if path then
 		tabInfo.path = path
-		tabInfo.env = shell.makeEnv()
 		tabInfo.args = args
 		tabInfo.title = fs.getName(path):match('([^%.]+)')
 
@@ -329,25 +314,21 @@ function shell.newTab(tabInfo, ...)
 			table.insert(tabInfo.args, 1, tabInfo.path)
 			tabInfo.path = 'sys/apps/shell.lua'
 		end
-		return _ENV.multishell.openTab(tabInfo)
+		return _ENV.multishell.openTab(_ENV, tabInfo)
 	end
 	return nil, 'No such program'
 end
 
-function shell.openTab(...)
-	-- needs to use multishell.launch .. so we can run with stock multishell
-	local tWords = tokenise( ... )
-	local sCommand = tWords[1]
-	if sCommand then
-		local sPath = shell.resolveProgram(sCommand)
-		if sPath == "sys/apps/shell.lua" then
-			return _ENV.multishell.launch(shell.makeEnv(), sPath, table.unpack(tWords, 2))
-		else
-			return _ENV.multishell.launch(shell.makeEnv(), "sys/apps/shell.lua", sCommand, table.unpack(tWords, 2))
-		end
+if not _ENV.multishell then
+	function shell.newTab()
+		error('Multishell is not available')
 	end
 end
 
+function shell.openTab(...)
+	return shell.newTab({ }, ...)
+end
+
 function shell.openForegroundTab( ... )
 	return shell.newTab({ focused = true }, ...)
 end
diff --git a/sys/autorun/hotkeys.lua b/sys/autorun/hotkeys.lua
index ab591e0..ab65ad6 100644
--- a/sys/autorun/hotkeys.lua
+++ b/sys/autorun/hotkeys.lua
@@ -10,9 +10,8 @@ if multishell and multishell.getTabs then
 		local tab = kernel.getFocused()
 		if tab and not tab.noTerminate then
 			multishell.terminate(tab.uid)
-			multishell.openTab({
+			multishell.openTab(tab.env, {
 				path = tab.path,
-				env = tab.env,
 				args = tab.args,
 				focused = true,
 			})
diff --git a/sys/autorun/log.lua b/sys/autorun/log.lua
index 3540f0d..c43c1dc 100644
--- a/sys/autorun/log.lua
+++ b/sys/autorun/log.lua
@@ -39,7 +39,7 @@ local function systemLog()
 	keyboard.removeHotkey('control-d')
 end
 
-kernel.run({
+kernel.run(_ENV, {
 	title = 'System Log',
 	fn = systemLog,
 	noTerminate = true,
diff --git a/sys/init/5.network.lua b/sys/init/5.network.lua
index d526b62..8e31fa4 100644
--- a/sys/init/5.network.lua
+++ b/sys/init/5.network.lua
@@ -15,7 +15,7 @@ do
 end
 
 local function startNetwork()
-	kernel.run({
+	kernel.run(_ENV, {
 		title = 'Net daemon',
 		path = 'sys/apps/netdaemon.lua',
 		hidden = true,
diff --git a/sys/init/7.multishell.lua b/sys/init/7.multishell.lua
index f37033c..3d2f0ba 100644
--- a/sys/init/7.multishell.lua
+++ b/sys/init/7.multishell.lua
@@ -8,7 +8,6 @@ local kernel     = _G.kernel
 local keys       = _G.keys
 local os         = _G.os
 local printError = _G.printError
-local shell      = _ENV.shell
 local window     = _G.window
 
 local parentTerm = _G.device.terminal
@@ -18,7 +17,7 @@ local tabsDirty = false
 local closeInd = Util.getVersion() >= 1.76 and '\215' or '*'
 local multishell = { }
 
-shell.setEnv('multishell', multishell)
+_ENV.multishell = multishell
 
 kernel.window.reposition(1, 2, w, h - 1)
 
@@ -93,22 +92,21 @@ function multishell.getTabs()
 	return kernel.routines
 end
 
-function multishell.launch( tProgramEnv, sProgramPath, ... )
+function multishell.launch(env, path, ...)
 	-- backwards compatibility
-	return multishell.openTab({
-		env = tProgramEnv,
-		path = sProgramPath,
+	return multishell.openTab(env, {
+		path = path,
 		args = { ... },
 	})
 end
 
-function multishell.openTab(tab)
+function multishell.openTab(env, tab)
 	if not tab.title and tab.path then
 		tab.title = fs.getName(tab.path):match('([^%.]+)')
 	end
 	tab.title = tab.title or 'untitled'
 	tab.window = tab.window or window.create(parentTerm, 1, 2, w, h - 1, false)
-	tab.onExit = function(self, result, err)
+	tab.onExit = tab.onExit or function(self, result, err)
 		if not result and err and err ~= 'Terminated' or (err and err ~= 0) then
 			self.terminal.setBackgroundColor(colors.black)
 			if tonumber(err) then
@@ -131,14 +129,17 @@ function multishell.openTab(tab)
 		end
 	end
 
-	local routine = kernel.run(tab)
+	local routine, message = kernel.run(env, tab)
 
-	if tab.focused then
-		multishell.setFocus(routine.uid)
-	else
-		redrawMenu()
+	if routine then
+		if tab.focused then
+			multishell.setFocus(routine.uid)
+		else
+			redrawMenu()
+		end
 	end
-	return routine.uid
+
+	return routine and routine.uid, message
 end
 
 function multishell.hideTab(tabId)
@@ -316,15 +317,22 @@ kernel.hook('mouse_scroll', function(_, eventData)
 end)
 
 kernel.hook('kernel_ready', function()
-	overviewId = multishell.openTab({
-		path = config.launcher or 'sys/apps/Overview.lua',
+	overviewId = multishell.openTab(_ENV, {
+		path = 'sys/apps/shell.lua',
+		args = { config.launcher or 'sys/apps/Overview.lua' },
 		isOverview = true,
 		noTerminate = true,
 		focused = true,
 		title = '+',
+		onExit = function(_, s, m)
+			if not s then
+				kernel.halt(s, m)
+			end
+		end,
 	})
+	multishell.setTitle(overviewId, '+')
 
-	multishell.openTab({
+	multishell.openTab(_ENV, {
 		path = 'sys/apps/shell.lua',
 		args = { 'sys/apps/autorun.lua' },
 		title = 'Autorun',
diff --git a/sys/kernel.lua b/sys/kernel.lua
index 1535b2c..5f86bd4 100644
--- a/sys/kernel.lua
+++ b/sys/kernel.lua
@@ -108,6 +108,38 @@ function Routine:resume(event, ...)
 	end
 end
 
+function Routine:run()
+	self.co = self.co or coroutine.create(function()
+		local result, err, fn
+
+		if self.fn then
+			fn = self.fn
+			_G.setfenv(fn, self.env)
+		elseif self.path then
+			fn, err = loadfile(self.path, self.env)
+		elseif self.chunk then
+			fn, err = load(self.chunk, self.title, nil, self.env)
+		end
+
+		if fn then
+			result, err = trace(fn, table.unpack(self.args or { } ))
+		else
+			err = err or 'kernel: invalid routine'
+		end
+
+		pcall(self.onExit, self, result, err)
+		self:cleanup()
+
+		if not result then
+			error(err)
+		end
+	end)
+
+	table.insert(kernel.routines, self)
+
+	return self:resume()
+end
+
 -- override if any post processing is required
 function Routine:onExit(status, message) -- self, status, message
 	if not status and message ~= 'Terminated' then
@@ -134,9 +166,14 @@ function kernel.getShell()
 	return shell
 end
 
-kernel.makeEnv = shell.makeEnv
+-- each routine inherits the parent's env
+function kernel.makeEnv(env)
+	env = setmetatable(Util.shallowCopy(env or _ENV), { __index = _G })
+	_G.requireInjector(env)
+	return env
+end
 
-function kernel.newRoutine(args)
+function kernel.newRoutine(env, args)
 	kernel.UID = kernel.UID + 1
 
 	local routine = setmetatable({
@@ -147,52 +184,16 @@ function kernel.newRoutine(args)
 	}, { __index = Routine })
 
 	Util.merge(routine, args)
-	routine.env = args.env or shell.makeEnv()
+	routine.env = args.env or kernel.makeEnv(env)
 	routine.terminal = routine.terminal or routine.window
 
 	return routine
 end
 
-local function xprun(env, path, ...)
-	setmetatable(env, { __index = _G })
-	local fn, m = loadfile(path, env)
-	if fn then
-		return trace(fn, ...)
-	end
-	return fn, m
-end
-
-function kernel.launch(routine)
-	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 = xprun(routine.env, routine.path, table.unpack(routine.args or { } ))
-		else
-			err = 'kernel: invalid routine'
-		end
-
-		pcall(routine.onExit, routine, result, err)
-		routine:cleanup()
-
-		if not result then
-			error(err)
-		end
-	end)
-
-	table.insert(kernel.routines, routine)
-
-	local s, m = routine:resume()
-
-	return s and routine.uid, m
-end
-
-function kernel.run(args)
-	local routine = kernel.newRoutine(args)
-	kernel.launch(routine)
-	return routine
+function kernel.run(env, args)
+	local routine = kernel.newRoutine(env, args)
+	local s, m = routine:run()
+	return s and routine, m
 end
 
 function kernel.raise(uid)
@@ -314,9 +315,10 @@ local function init(...)
 	for _,file in ipairs(files) do
 		local level = file:match('(%d).%S+.lua') or 99
 		if tonumber(level) <= runLevel then
+			-- All init programs run under the original shell
 			local s, m = shell.run(fs.combine(dir, file))
 			if not s then
-				error(m)
+				error(m, -1)
 			end
 			os.sleep(0)
 		end
@@ -331,7 +333,7 @@ local function init(...)
 			shell.run('sys/apps/autorun.lua')
 
 			local win = window.create(kernel.terminal, 1, 1, w, h, true)
-			local s, m = kernel.run({
+			local s, m = kernel.run(_ENV, {
 				title = args[1],
 				path = 'sys/apps/shell.lua',
 				args = args,
@@ -349,7 +351,7 @@ local function init(...)
 	end
 end
 
-kernel.run({
+kernel.run(_ENV, {
 	fn = init,
 	title = 'init',
 	args = { ... },
diff --git a/sys/modules/opus/crypto/chacha20.lua b/sys/modules/opus/crypto/chacha20.lua
index 9db2d08..c98654c 100644
--- a/sys/modules/opus/crypto/chacha20.lua
+++ b/sys/modules/opus/crypto/chacha20.lua
@@ -100,7 +100,7 @@ local function crypt(data, key, nonce, cntr, round)
 	cntr = tonumber(cntr) or 1
 	round = tonumber(round) or 20
 
-	local throttle = Util.throttle(function() _syslog('throttle') end)
+	local throttle = Util.throttle()
 	local out = {}
 	local state = initState(key, nonce, cntr)
 	local blockAmt = math.floor(#data/64)
diff --git a/sys/modules/opus/event.lua b/sys/modules/opus/event.lua
index 924461e..5560beb 100644
--- a/sys/modules/opus/event.lua
+++ b/sys/modules/opus/event.lua
@@ -58,6 +58,14 @@ function Routine:resume(event, ...)
 		else
 			s, m = coroutine.resume(self.co, event, ...)
 		end
+
+		if not s and event ~= 'terminate' then
+			if m and debug and debug.traceback then
+				local t = (debug.traceback(self.co, 1)) or ''
+				m = m .. '\n' .. t:match('%d\n(.+)')
+			end
+		end
+
 		if self:isDead() then
 			self.co = nil
 			self.filter = nil
diff --git a/sys/modules/opus/trace.lua b/sys/modules/opus/trace.lua
index c8cf2a9..bb12fde 100644
--- a/sys/modules/opus/trace.lua
+++ b/sys/modules/opus/trace.lua
@@ -32,95 +32,63 @@ local function traceback(x)
 	end
 end
 
-local function trim_traceback(target, marker)
-	local ttarget, tmarker = {}, {}
-	for line in target:gmatch("([^\n]*)\n?") do ttarget[#ttarget + 1] = line end
-	for line in marker:gmatch("([^\n]*)\n?") do tmarker[#tmarker + 1] = line end
+local function trim_traceback(target)
+	local t = { }
+	local filters = {
+		"%[C%]: in function 'xpcall'",
+		"(...tail calls...)",
+		"xpcall: $",
+		"trace.lua:%d+:",
+	}
 
---[[
-	TODO : fix this trace
-	Anavrins - if you could take a look, it would be appreciated
-	-- basically i want the stack logged in a more readable
-	-- format and the normal code/error message to be returned
-
-	-- unsure why the traceback method concatenates the stack
-	-- when it can just be returned as a table - would make
-	-- filtering much simpler
-
-	-- the following seems to reduce the stacktrace way too
-	-- much - losing most of the relevant call stack
-
-	-- i have modified this a bit from the original - not sure
-	-- if my changes are causing the issues or not
-
-	-- Trim identical suffixes
-	local t_len, m_len = #ttarget, #tmarker
-	while t_len >= 3 and ttarget[t_len] == tmarker[m_len] do
-		table.remove(ttarget, t_len)
-		t_len, m_len = t_len - 1, m_len - 1
+	local function matchesFilter(line)
+		for _, filter in pairs(filters) do
+			if line:match(filter) then
+				return true
+			end
+		end
 	end
 
-	-- Trim elements from this file and xpcall invocations
-	while t_len >= 1 and ttarget[t_len]:find("^\tstack_trace%.lua:%d+:") or
-				ttarget[t_len] == "\t[C]: in function 'xpcall'" or ttarget[t_len] == "  xpcall: " do
-		table.remove(ttarget, t_len)
-		t_len = t_len - 1
+	for line in target:gmatch("([^\n]*)\n?") do
+		if not matchesFilter(line) then
+			table.insert(t, line)
+		end
 	end
-]]
-	ttarget[#ttarget] = nil -- remove 2 calls added by the added xpcall
-	ttarget[#ttarget] = nil
 
-	return ttarget
+	return t
 end
 
---- Run a function with
 return function (fn, ...)
-	-- So this is rather grim: we need to get the full traceback and current one and remove
-	-- the common prefix
-	local trace
-	local args = { ... }
-
 	-- xpcall in Lua 5.1 does not accept parameters
 	-- which is not ideal
+	local args = { ... }
 	local res = table.pack(xpcall(function()
 		return fn(table.unpack(args))
 	end, traceback))
 
-	if not res[1] then 
-		trace = traceback("trace.lua:1:")
-	end
 	local ok, err = res[1], res[2]
 
 	if not ok and err ~= nil then
-		trace = trim_traceback(err, trace)
+		local trace = trim_traceback(err)
 
-		-- Find the position where the stack traceback actually starts
-		local trace_starts
-		for i = #trace, 1, -1 do
-			if trace[i] == "stack traceback:" then trace_starts = i; break end
-		end
-
-		_G._syslog('')
-		for _, line in pairs(trace) do
-			_G._syslog(line)
-		end
-
-		-- If this traceback is more than 15 elements long, keep the first 9, last 5
-		-- and put an ellipsis between the rest
-		local max = 10
-		if trace_starts and #trace - trace_starts > max then
-			local keep_starts = trace_starts + 7
-			for i = #trace - trace_starts - max, 0, -1 do
-				table.remove(trace, keep_starts + i)
+		err = { }
+		while true do
+			local line = table.remove(trace, 1)
+			if not line or line == 'stack traceback:' then
+				break
+			end
+			table.insert(err, line)
+		end
+		err = table.concat(err, '\n')
+
+		_G._syslog('\n' .. err .. '\n' .. 'stack traceback:')
+		for _, v in ipairs(trace) do
+			if v ~= 'stack traceback:' then
+				_G._syslog(v:gsub("in function", "in"))
 			end
-			table.insert(trace, keep_starts, "  ...")
 		end
 
-		for k, line in pairs(trace) do
-			trace[k] = line:gsub("in function", " in")
-		end
-
-		return false, table.remove(trace, 1), table.concat(trace, "\n")
+		return ok, err
 	end
 
 	return table.unpack(res, 1, res.n)
diff --git a/sys/modules/opus/ui.lua b/sys/modules/opus/ui.lua
index fb67603..25c5083 100644
--- a/sys/modules/opus/ui.lua
+++ b/sys/modules/opus/ui.lua
@@ -117,7 +117,7 @@ function UI:init()
 
 			if ie.code == 'control-shift-mouse_click' then -- hack
 				local event = currentPage:pointToChild(x, y)
-				_ENV.multishell.openTab({
+				_ENV.multishell.openTab(_ENV, {
 					path = 'sys/apps/Lua.lua',
 					args = { event.element, self, _ENV },
 					focused = true })