diff --git a/patch/.gitignore b/patch/.gitignore
new file mode 100644
index 0000000..0d0b0f4
--- /dev/null
+++ b/patch/.gitignore
@@ -0,0 +1,5 @@
+*.z64
+patchme
+lips
+entrances.asm
+crc32.asm
diff --git a/patch/code.asm b/patch/code.asm
new file mode 100644
index 0000000..3f8ca1a
--- /dev/null
+++ b/patch/code.asm
@@ -0,0 +1,62 @@
+[link_save]: 0x801EF670
+ [has_completed_intro]: 0x5
+ [have_tatl]: 0x22
+ [player_name]: 0x2C
+ [scene_flags]: 0x470
+ [week_event_reg]: 0xEF8
+ [voidout_type]: 0x3CB0
+ [voidout_exit]: 0x3CC4
+ [exit_mod_setter]: 0x3F4A
+ [scene_flags_ingame]: 0x3F68
+
+[starting_exit]: 0x9F87C
+[default_save]: 0x120DD8
+
+.org @starting_exit
+    li      t8, 0xD800 ; modified code
+    li      t4, 0xD800 ; modified code
+
+.org @default_save
+    .ascii  "\0\0\0\0\0\0" ; ZELDA3
+    .half   1 ; SoT count
+    .ascii  ">>>>>>>>" ; player name
+    .half   0x30 ; hearts
+    .half   0x30 ; max hearts
+    .byte   1 ; magic level
+    .byte   0x30 ; magic amount
+    .half   0 ; rupees
+    .word   0 ; navi timer
+    .byte   1 ; has normal magic
+    .byte   0 ; has double magic
+    .half   0 ; double defense
+    .half   0xFF00 ; unknown
+    .half   0x0000 ; owls hit
+    .word   0xFF000008 ; unknown
+    .word   0x4DFFFFFF ; human buttons
+    .word   0x4DFFFFFF ; goron buttons
+    .word   0x4DFFFFFF ; zora buttons
+    .word   0xFDFFFFFF ; deku buttons
+    .word   0x00FFFFFF ; equipped slots
+    .word   0xFFFFFFFF ; unknown
+    .word   0xFFFFFFFF ; unknown
+    .word   0xFFFFFFFF ; unknown
+    .half   0x0011 ; tunic & boots
+    .half   0 ; unknown
+    ; inventory items
+    .byte   0x00, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF ; ocarina, nothing else
+    .byte   0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF
+    .byte   0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF
+    .byte   0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF
+    ; mask items
+    .byte   0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x32 ; deku mask, nothing else
+    .byte   0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF
+    .byte   0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF
+    .byte   0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF
+    ; item quantities
+    .byte   0, 0, 0, 0, 0, 0
+    .byte   0, 0, 0, 0, 0, 0
+    .byte   0, 0, 0, 0, 0, 0
+    .byte   0, 0, 0, 0, 0, 0
+    ;
+    .word   0 ; upgrades
+    .word   0x00003000 ; quest status (set song of time and song of healing)
diff --git a/patch/mm-randomizer b/patch/mm-randomizer
new file mode 100755
index 0000000..1394a4d
--- /dev/null
+++ b/patch/mm-randomizer
@@ -0,0 +1,26 @@
+#!/usr/bin/env bash
+set -e
+
+inject=../Lua/inject
+sha1=d6133ace5afaa0882cf214cf88daba39e266c078
+extracted=../dump/mm-US10-"$sha1"
+rom=../../roms/everything/"Legend of Zelda, The - Majora's Mask (U) [!].z64"
+lips=../Lua/lib/lips
+code="0031 V00B3C000"
+
+if ! [ -d "$extracted" ]; then
+    ../z64dump.py "$rom"
+    mv "$sha1" "$extracted"
+fi
+[ -d patchme ] && rm -r patchme
+cp -r "$extracted" patchme
+
+# don't copy entire dir; avoid copying dotfiles (.git)
+mkdir -p lips
+cp "$lips"/* lips
+
+cp "$inject/"{crc32,entrances}.asm .
+luajit patch.lua code.asm patchme/"$code"
+
+../z64dump.py patchme
+mv patchme.z64 mm-randomizer.z64
diff --git a/patch/patch.lua b/patch/patch.lua
new file mode 100644
index 0000000..6df5ac5
--- /dev/null
+++ b/patch/patch.lua
@@ -0,0 +1,22 @@
+package.path = package.path..";./?/init.lua"
+
+local assemble = require "lips"
+
+local function inject(patch, target)
+    local f = io.open(target, 'r+b')
+
+    local function write(pos, line)
+        assert(#line == 2, "that ain't const")
+        -- TODO: write hex dump format of written bytes
+        --print(("%08X"):format(pos), line)
+        f:seek('set', pos)
+        f:write(string.char(tonumber(line, 16)))
+    end
+
+    -- offset assembly labels so they work properly, and assemble!
+    assemble(patch, write, {unsafe=true, offset=0})
+
+    f:close()
+end
+
+inject(arg[1], arg[2])