design consideratins for a simple (semantic) contact management app

hi all,

as a simple excercise i would like to build a simple contact
management app ( domain: generic business... contacts, accounts,
employees, relations, etc ) as follows.

*a central server with a triple store
** inference engine
** contexts / named graphs
*several user accounts
*a user interface that allows users to
** create / delete statements
*** contexts are used to keep track of provenance of statements
** sparql and simple browsing
*an ontology ( plus inference layer ) that allows me to, at least:
** use or define some common inverse functional properties ( ssn /
email / internal id / phone extension ) and perform smushing.
** define basic contact info plus some relationships ( hierarchy,
relation to an organization, etc. transitivity would be nice in
hierarchical relationships )

what storage / inference stack would you use?
any recommended ontologies?
design considerations / ideas?
dev workflow?

doesn't need to be performant at all. we're talking very small numbers here.

thx ;)
aldo

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::::: Aldo Bucchi :::::
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