At the time Google tended to destroy companies they bought by insisting they rewrite their product using Google infrastructure.
By the time that was complete, the product had died.
For some reason, YouTube was allowed to keep their infrastructure.
By the time that was complete, the product had died.
For some reason, YouTube was allowed to keep their infrastructure.
Google's CDN was largely written for YouTube.
https://vitess.io/docs/overview/history/
Keeping mysql over bigtable seems like a much bigger deal than the application layer being python vs c++/java/go.
"The back-end was Python... ...."
okay.
I was not in YT. I was only told their backend was Python by people who were. I can't explain that paper OP saw. Could be it reflected reality and I'm wrong; could be it was only a design.
I do know for a fact that they still had their own experiment infrastructure, which does suggest that the backend was still legacy.
There might also be a lot of confusion over "backend" vs. "frontend" terminology. Like the other poster mentioned, "frontend" at Google usually means the webserver and sometimes extends back to various application-level services. Basically everything that involves user interaction. Experiment infrastructure has been part of the frontend in every system I've worked with at Google (which now includes Search, Google+, GFiber, Doodles, AndroidTV, and Assistant), though the flags often get plumbed back to backends to alter behavior there.
By "backend" I mean the storage & offline processing areas. BigTable, Colossus, MapReduce, various blob stores, training machine-learning models, etc. This is the part of YT that (in my understanding) was rewritten to use Google technologies.
Perhaps giving a list of those dead products would be helpful for discussions, modulo those products with merely brand changes.