diff --git a/init.lua b/init.lua
index 45b68bc..122ea87 100644
--- a/init.lua
+++ b/init.lua
@@ -78,7 +78,7 @@ end
 local load_module, get_resource, loadfile_exports
 modlib = setmetatable({
 	-- TODO bump on release
-	version = 63,
+	version = 64,
 	modname = minetest and minetest.get_current_modname(),
 	dir_delim = rawget(_G, "DIR_DELIM") or "/",
 	_RG = setmetatable({}, {
diff --git a/persistence.lua b/persistence.lua
index ebdd5d9..602e0d1 100644
--- a/persistence.lua
+++ b/persistence.lua
@@ -2,11 +2,11 @@ lua_log_file = {}
 local files = {}
 local metatable = {__index = lua_log_file}
 
--- TODO register on shutdown
-
 function lua_log_file.new(file_path, root)
     local self = setmetatable({file_path = assert(file_path), root = root}, metatable)
-    files[self] = true
+    if minetest then
+        files[self] = true
+    end
     return self
 end
 
@@ -53,11 +53,13 @@ function lua_log_file:close()
     files[self] = nil
 end
 
-minetest.register_on_shutdown(function()
-    for self in pairs(files) do
-        self.file:close()
-    end
-end)
+if minetest then
+    minetest.register_on_shutdown(function()
+        for self in pairs(files) do
+            self.file:close()
+        end
+    end)
+end
 
 -- TODO use shorthand notations
 function lua_log_file:dump(value)