TinyCDB is a very fast and simple package for creating and reading
constant data bases, a data structure introduced by Dan J. Bernstein
in his cdb package. It may be used to speed up searches in a sequence
of (key,value) pairs with very big number of records. Example usage
is indexing a big list of users - where a search will require linear
reading of a large /etc/passwd file, and for many other tasks. It's
usage/API is similar to ones found in BerkeleyDB, gdbm and traditional
*nix dbm/ndbm libraries, and is compatible in great extent to
cdb-0.75 package by Dan Bernstein.

CDB is a constant database, that is, it cannot be updated at a
runtime, only rebuilt. Rebuilding is atomic operation and is very
fast - much faster than of many other similar packages. Once created,
CDB may be queried, and a query takes very little time to complete.

Homepage:
https://www.corpit.ru/mjt/tinycdb.html
