It should be possible to customize the location of the websearch database (currently it must in a ~/.LPSearch.db file).
This can be useful if one wants to start different servers indexing different libraries or to allow collaborative management of a server in work (for instance the one referencing the HOL-Light library) without having to use different ~/.LPSearch.db files (one for each user launching the server).

Note that an alternative solution would be to generate the ~/.LPSearch.db file then move it to a custom folder and start the webserver from that location.
Then, Lambdapi should look for it in the current folder since it fails to find it in the HOME folder of the user. This solution is however not very elegant.