diff --git a/contrib/btc_all.lua b/contrib/btc_all.lua
index 5942711..b107a47 100644
--- a/contrib/btc_all.lua
+++ b/contrib/btc_all.lua
@@ -7,7 +7,7 @@
 local setmetatable = setmetatable
 local pcall = pcall
 local helpers = require("vicious.helpers")
-local spawn = require("awful.spawn")
+local spawn = require("vicious.spawn")
 
 local success, json = pcall(require, "cjson")
 if not success then
@@ -51,6 +51,13 @@ function btc_all.async(format, warg, callback)
 
     spawn.easy_async(cmd, function(stdout) callback(parse(stdout)) end)
 end
+
+local function worker(format, warg)
+    local ret
+    btc_all.async(format, warg, function (price) ret = price end)
+    while ret == nil do end
+    return ret
+end
 -- }}}
 
-return btc_all
+return setmetatable(btc_all, { __call = function(_, ...) return worker(...) end })
diff --git a/spawn.lua b/spawn.lua
index d252684..858d15f 100644
--- a/spawn.lua
+++ b/spawn.lua
@@ -16,8 +16,14 @@
 -- You should have received a copy of the GNU Affero General Public License
 -- along with Vicious.  If not, see <https://www.gnu.org/licenses/>.
 
-local status, spawn = pcall(require, "awful.spawn")
-if status then return spawn end
+local status, awful = pcall(require, "awful")
+if status then
+    local spawn = awful.spawn
+    function spawn.with_line_callback_with_shell(cmd, callbacks)
+        spawn.with_line_callback({ awful.util.shell, "-c", cmd }, callbacks)
+    end
+    return spawn
+end
 
 local io = { popen = io.popen }
 
@@ -26,7 +32,7 @@ local io = { popen = io.popen }
 local spawn = {}
 
 --- Spawn a program and capture its output line by line.
--- @tparam string|table cmd The command.
+-- @tparam string cmd The command.
 -- @tab callbacks Table containing callbacks that should be invoked on
 --   various conditions.
 -- @tparam[opt] function callbacks.stdout Function that is called with each
@@ -44,7 +50,7 @@ local spawn = {}
 --   For "signal", the second argument is the signal causing process
 --   termination.
 -- @treturn boolean|nil true if cmd terminated successfully, or nil otherwise
-function spawn.with_line_callback(cmd, callbacks)
+function spawn.with_line_callback_with_shell(cmd, callbacks)
     local stdout_callback, stdout = callbacks.stdout, io.popen(cmd)
     for line in stdout:lines() do stdout_callback(line) end
     if callbacks.output_done then callbacks.output_done() end
@@ -55,7 +61,7 @@ function spawn.with_line_callback(cmd, callbacks)
 end
 
 --- Spawn a program and capture its output.
--- @tparam string|table cmd The command.
+-- @tparam string cmd The command.
 -- @tab callback Function with the following arguments
 --   @tparam string callback.stdout Output on stdout.
 --   @tparam string callback.stderr Output on stderr,
@@ -64,7 +70,7 @@ end
 --   @tparam integer callback.exitcode Exit code (exit code or signal number,
 --     depending on "exitreason").
 -- @treturn boolean|nil true if cmd terminated successfully, or nil otherwise
-function spawn.easy_async(cmd, callback)
+function spawn.easy_async_with_shell(cmd, callback)
     local out_stream = io.popen(cmd)
     local stdout = out_stream:read("*all")
     local success, reason, code = out_stream:close()    -- requiring Lua 5.2
@@ -72,5 +78,9 @@ function spawn.easy_async(cmd, callback)
     return success
 end
 
+-- Since io.popen always use a shell
+spawn.easy_async = spawn.easy_async_with_shell
+spawn.with_line_callback = spawn.with_line_callback_with_shell
+
 return spawn
 -- vim: filetype=lua:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:textwidth=80
diff --git a/widgets/pkg_all.lua b/widgets/pkg_all.lua
index 62cc61e..cda1b06 100644
--- a/widgets/pkg_all.lua
+++ b/widgets/pkg_all.lua
@@ -7,7 +7,7 @@
 local io = { popen = io.popen }
 local math = { max = math.max }
 local setmetatable = setmetatable
-local spawn = require("awful.spawn")
+local spawn = require("vicious.spawn")
 -- }}}
 
 
@@ -15,39 +15,32 @@ local spawn = require("awful.spawn")
 -- vicious.widgets.pkg
 local pkg_all = {}
 
+local PKGMGR = {
+    ["Arch"] = { cmd = "pacman -Qu" },
+    ["Arch C"] = { cmd = "checkupdates" },
+    ["Arch S"] = { cmd = "yes | pacman -Sup", sub = 1 },
+    ["Debian"] = { cmd = "apt list --upgradable", sub = 1 },
+    ["Ubuntu"] = { cmd = "apt list --upgradable", sub = 1 },
+    ["Fedora"] = { cmd = "dnf check-update", sub = 2 },
+    ["FreeBSD"] = { cmd = "pkg version -I -l '<'" },
+    ["Mandriva"] = { cmd = "urpmq --auto-select" }
+}
 
 -- {{{ Packages widget type
 function pkg_all.async(format, warg, callback)
-    if not warg then return end
+    if not warg then return callback{} end
+    local pkgmgr = PKGMGR[warg]
 
-    -- Initialize counters
-    local manager = {
-        ["Arch"]   = { cmd = "pacman -Qu" },
-        ["Arch C"] = { cmd = "checkupdates" },
-        ["Arch S"] = { cmd = "yes | pacman -Sup", sub = 1 },
-        ["Debian"] = { cmd = "apt-show-versions -u -b" },
-        ["Ubuntu"] = { cmd = "aptitude search '~U'" },
-        ["Fedora"] = { cmd = "yum list updates", sub = 3 },
-        ["FreeBSD"] ={ cmd = "pkg version -I -l '<'" },
-        ["Mandriva"]={ cmd = "urpmq --auto-select" }
-    }
-
-    -- Check if updates are available
-    local function parse(str, skiprows)
-        local size, lines, first = 0, "", skiprows or 0
-        for line in str:gmatch("[^\r\n]+") do
-            if size >= first then
-                lines = lines .. (size == first and "" or "\n") .. line
-            end
+    local size, lines = -pkgmgr.sub, ""
+    spawn.with_line_callback_with_shell(pkgmgr.cmd, {
+        stdout = function (str)
             size = size + 1
+            if size > 0 then lines = lines .. str .. "\n" end
+        end,
+        output_done = function ()
+            callback{ size, lines }
         end
-        size = math.max(size-first, 0)
-        return {size, lines}
-    end
-
-    -- Select command
-    local _pkg = manager[warg]
-    spawn.easy_async(_pkg.cmd, function(stdout) callback(parse(stdout, _pkg.sub)) end)
+    })
 end
 -- }}}
 
diff --git a/widgets/volume_linux.lua b/widgets/volume_linux.lua
index 0fd6820..96725f0 100644
--- a/widgets/volume_linux.lua
+++ b/widgets/volume_linux.lua
@@ -9,6 +9,7 @@ local io = { popen = io.popen }
 local setmetatable = setmetatable
 local string = { match = string.match }
 local helpers = require("vicious.helpers")
+local spawn = require("vicious.spawn")
 -- }}}
 
 
@@ -16,6 +17,11 @@ local helpers = require("vicious.helpers")
 -- vicious.widgets.volume
 local volume_linux = {}
 
+local STATES = { on = '🔉', off = '🔈' }
+
+function volume_linux.async(format, warg, callback)
+    if not warg then return callback{} end
+end
 
 -- {{{ Volume widget type
 local function worker(format, warg)
diff --git a/widgets/weather_all.lua b/widgets/weather_all.lua
index 7c5a96d..7b38208 100644
--- a/widgets/weather_all.lua
+++ b/widgets/weather_all.lua
@@ -11,7 +11,7 @@ local math = { ceil = math.ceil }
 local string = { match = string.match }
 
 -- Awesome library for spawning programs
-local spawn = require"awful.spawn"
+local spawn = require"vicious.spawn"
 
 local helpers = require("vicious.helpers")
 -- }}}
@@ -86,12 +86,12 @@ local function parse(ws)
 end
 
 function weather_all.async(format, warg, callback)
-    if not warg then return end
+    if not warg then return callback{} end
 
     -- Get weather forceast by the station ICAO code, from:
     -- * US National Oceanic and Atmospheric Administration
     local url = ("https://tgftp.nws.noaa.gov/data/observations/metar/decoded/%s.TXT"):format(warg)
-    local cmd = "curl -fs " .. helpers.shellquote(url)
+    local cmd = "curl -fs " .. url
     spawn.easy_async(cmd, function (stdout) callback(parse(stdout)) end)
 end