diff --git a/main.lua b/main.lua
index 15c1836..7ed2dc8 100644
--- a/main.lua
+++ b/main.lua
@@ -1,24 +1,28 @@
+-- hacks for FCEUX being dumb.
+local _error = error
+local _assert = assert
+local function error_(msg, level)
+    if level == nil then level = 1 end
+    print()
+    print(debug.traceback(msg, 1 + level):gsub("\n", "\r\n"))
+    _error(msg, level)
+end
+local function assert_(cond, msg)
+    if cond then return cond end
+    msg = msg or "nondescript"
+    print()
+    print(debug.traceback(msg, 2):gsub("\n", "\r\n"))
+    _error("assertion failed!")
+end
+rawset(_G, 'error', error_)
+rawset(_G, 'assert', assert_)
+
 -- be strict about globals.
-
 local mt = getmetatable(_G)
-if mt == nil then
-    mt = {}
-    setmetatable(_G, mt)
-end
-
-function mt.__newindex(t, n, v)
-    error("cannot assign undeclared global '" .. tostring(n) .. "'", 2)
-end
-
-function mt.__index(t, n)
-    error("cannot use undeclared global '" .. tostring(n) .. "'", 2)
-end
-
-local function globalize(t)
-    for k, v in pairs(t) do
-        rawset(_G, k, v)
-    end
-end
+if mt == nil then mt = {} setmetatable(_G, mt) end
+function mt.__newindex(t, n, v) error("cannot assign undeclared global '" .. tostring(n) .. "'", 2) end
+function mt.__index(t, n) error("cannot use undeclared global '" .. tostring(n) .. "'", 2) end
+local function globalize(t) for k, v in pairs(t) do rawset(_G, k, v) end end
 
 -- configuration and globals.