diff --git a/rockspecs/mmapfile-3-1.rockspec b/rockspecs/mmapfile-3-1.rockspec
new file mode 100644
index 0000000..1208651
--- /dev/null
+++ b/rockspecs/mmapfile-3-1.rockspec
@@ -0,0 +1,34 @@
+package = "mmapfile"
+version = "3-1"
+source =
+{
+  url = "git://github.com/geoffleyland/lua-mmapfile.git",
+  branch = "master",
+  tag = "v3",
+}
+description =
+{
+  summary = "Simple memory-mapped files",
+  homepage = "http://github.com/geoffleyland/lua-mmapfile",
+  license = "MIT/X11",
+  maintainer = "Geoff Leyland <geoff.leyland@incremental.co.nz>"
+}
+dependencies =
+{
+  'lua == 5.1',               -- should be "luajit >= 2.0.0"
+  platforms =
+  {
+    linux = { 'ljsyscall >= 0.9' },
+    macosx = { 'ljsyscall >= 0.9' },
+  }
+}
+build =
+{
+  type = "builtin",
+  modules =
+  {
+    mmapfile = "src-lua/mmapfile.lua",
+    ["mmapfile.unix"] = "src-lua/mmapfile/unix.lua",
+    ["mmapfile.windows"] = "src-lua/mmapfile/windows.lua",
+  },
+}