TODO:
- Write a README
- Use memvfs to avoid 512 /tmp limit - use up to 10GB of RAM.
- Parallelise S3 changeset reading
- S3 changeset writing
- Stale changeset stuff
- S3-less Dynamo-backed storage
- Defragmentation
- Mutation should take a Dynamo lock
- Build a Dynamo FTS engine on top of DDB streams
- Write CloudWatch metrics in EMF