A shelve-like key/value persistence API that uses JSON instead of pickle. This means that stored data structures cannot be arbitrary (pickleable) objects but must instead be simple data structures (lists, dicts, strings, ints, floats, null). But it also means that it's easy to use the data files from languages other than Python.
- Many backends. Applications can choose based on performance and other constraints and switch later without pain.
- Concurrency management & naive ACID in some form.
- Single-codebase Python 2 and 3 compatibility.
- Unicode keys?
- Extra niceness for indexing and such?