[sethammons]

Vendoring is checking in your dependencies with the source. You can def consider that a local cache. The next step up is to run your own proxy server (pretty much a package server / mirror). Next is to use a service like artifacory that does similar.

[erik_seaberg]

We should call it a backup. Calling it a cache puts people in mind of size/hit ratio tradeoffs; what's needed is zero tolerance for loss of mission critical code.