Anardb provides persistent classes, which can have slots indexed in hash-tables, and the ability to perform ACID transactions on them from multiple processes simultaneously. It is a bit like a prevalent database.
It requires UN*X filesystem semantics and has been tested on Allegro 8.1 x86 and AMD64 but should be portable to SBCL, etc.
Repository: https://gitlab.common-lisp.net/vsedach/anardb
License: LLGPL
database ObjectStore