For the time I was working there I'm quite sure most of the tools were internally made by MS:
- they had their own map reduce
- they had their own service deployment and management system
- their own db and nosql
- etc...
about the search and relevance they are updated quite fast, sometimes with big code replacement. This means that even if powerset tech was used as a start (and I do think it was not, it was possibly adapted and integrated -- i believe the base code was msn/live) it is now changed in most of its pieces.
about the search and relevance they are updated quite fast, sometimes with big code replacement. This means that even if powerset tech was used as a start (and I do think it was not, it was possibly adapted and integrated -- i believe the base code was msn/live) it is now changed in most of its pieces.