diff --git a/bluon.lua b/bluon.lua
index 20af1b6..72b4175 100644
--- a/bluon.lua
+++ b/bluon.lua
@@ -1,5 +1,6 @@
 -- Localize globals
-local assert, error, ipairs, math, modlib, next, pairs, setmetatable, string, table, type, unpack = assert, error, ipairs, math, modlib, next, pairs, setmetatable, string, table, type, unpack
+local assert, error, ipairs, math_floor, math_huge, modlib, next, pairs, setmetatable, string, table_insert, type, unpack
+	= assert, error, ipairs, math.floor, math.huge, modlib, next, pairs, setmetatable, string, table.insert, type, unpack
 
 -- Set environment
 local _ENV = {}
@@ -61,8 +62,8 @@ local constants = {
 	[0] = "\2",
 	-- not possible as table entry as Lua doesn't allow +/-nan as table key
 	-- [0/0] = "\3",
-	[math.huge] = "\4",
-	[-math.huge] = "\5",
+	[math_huge] = "\4",
+	[-math_huge] = "\5",
 	[""] = "\20"
 }
 
@@ -297,18 +298,18 @@ function read(self, stream)
 		end
 		if type <= type_ranges.string then
 			local string = stream_read(uint(type - type_ranges.number))
-			table.insert(references, string)
+			table_insert(references, string)
 			return string
 		end
 		if type <= type_ranges.table then
 			type = type - type_ranges.string - 1
 			local tab = {}
-			table.insert(references, tab)
+			table_insert(references, tab)
 			if type == 0 then
 				return tab
 			end
 			local list_len = uint(type % 5)
-			local kv_len = uint(math.floor(type / 5))
+			local kv_len = uint(math_floor(type / 5))
 			for index = 1, list_len do
 				tab[index] = _read(stream_read(1))
 			end
diff --git a/luon.lua b/luon.lua
index 25ba639..0e19fdc 100644
--- a/luon.lua
+++ b/luon.lua
@@ -1,5 +1,5 @@
-local assert, next, pairs, pcall, error, type, table_insert, table_concat, string_format, setfenv, math_huge, loadfile, loadstring
-    = assert, next, pairs, pcall, error, type, table.insert, table.concat, string.format, setfenv, math.huge, loadfile, loadstring
+local assert, next, pairs, pcall, error, type, table_insert, table_concat, string_format, string_match, setfenv, math_huge, loadfile, loadstring
+    = assert, next, pairs, pcall, error, type, table.insert, table.concat, string.format, string.match, setfenv, math.huge, loadfile, loadstring
 local count_values = modlib.table.count_values
 
 -- Build a table with the succeeding character from A-Z
@@ -45,7 +45,7 @@ function serialize(object, write)
         end
     end
     local function is_short_key(key)
-        return not references[key] and type(key) == "string" and key:match"^[%a_][%a%d_]*$"
+        return not references[key] and type(key) == "string" and string_match(key, "^[%a_][%a%d_]*$")
     end
     local function dump(value)
         -- Primitive types
@@ -60,7 +60,7 @@ function serialize(object, write)
         end
         local type_ = type(value)
         if type_ == "number" then
-            return write(("%.17g"):format(value))
+            return write(string_format("%.17g", value))
         end
         -- Reference types: table and string
         local ref = references[value]