I am aware of Data::Denter and in fact use it for simpler persistence situations.. By stringification I mean stringification of the reference, rather than the frozen version. Stringification of the frozen version is fine. However, I see no elegant way to use Data::Denter to do what I'm trying to do; that is, something like DB_File, with caching etc. If I just Denter the hash and dump that into a file (DB or otherwise), I run into the problem of possibly not having enough memory to read it back. It might be possible to write my own module that uses DB_File as a backend, but stores Dentered data to the DB_File, and Undents it when FETCHing. But then my circular references get clobbered.