I am definitely in the multiple repository camp, but with one caveat (below). With the monolithic approach everybody is forced to be on the latest version (or

I am definitely in the multiple repository camp, but with one caveat (below). With the monolithic approach everybody is forced to be on the latest version (or to update to the latest version). There can be a lot of contention when trying to get things out - especially when things are moving fast. You need a lot of discipline to make it work and you also are forced to constantly update parts of the code you own. Also, we tend to forget about deployment and management of the build artifacts. I am willing to bet that bigCo's that do this have a separate system for managing the artifacts and performing the deployments. In the presence of a decent build and deployment system the only way to go is multiple repos - a logical separation per component / service. The build system can easily track dependencies via components via metadata associated with each of them. You can easily orchestrate builds when something happens, it's easier to rebuild only what changes and you get granular control over build artifacts.