I'm looking for some time for a good user self management. "Good" means: User can add their own accounts, gets approved (or not), can recover the password, ... Of course, there are plenty implementations of that available in the market - most wikis have that, as well as lots of other applications. But all of them are embedded-only, i.e. one has to use that web application and gets "vendor-locked". Isn't there anything open source and standalone available, following the basic unix principles of "do one thing and do it well"?