These are the interesting things that sticks out to me:
The understanding that storage system throughput is maximized by using sequential access patterns led to the creation of streaming, append-only transactional and indexing algorithms. Our approach is unique in that all database files (i.e. transactional state, indexes, and metadata) are streamed, append-only files.
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The CASI Tree breaks from a traditional b-tree on-disk approach, eliminating update in-place operations on fixed size pages. Instead, the CASI Tree is an append-only Purely Functional Tree data structure.
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A complete database audit trail is maintained when running in archival mode, making all previous database states available. These states may be queried in read-only mode, efficiently supporting read-only analytics of point-in-time transactional database states