Interesting comparison over on the HN thread: bolt db can use lots of memory and uses btree rather than lsm
They're based on different technologies. Bolt uses B-Trees and Badger/Rocks/Leveldb use LSM trees. Bolt also uses insane amounts of RAM and writes get slower and slower as the size of the database increases. (Personal experience, don't have benchmarks. Take this at face value.)
immudb is a high-speed immutable database that uses Badger:
https://github.com/codenotary/immudb
https://news.ycombinator.com/item?id=14335931HN thread