The answer to this question depends quite a lot on what is being developed. It's not like an engineer at Google could have their own local copy of google.com.

The answer to this question depends quite a lot on what is being developed. It's not like an engineer at Google could have their own local copy of google.com. Most of my career I've been in mobile development, so the code basis are typically smaller. I've always had the full code on my local development machine. But you have to connect to web services and back end databases, so there's usually development, test, and production environments.