I didn't say everyone globally, I said everyone on a development team, i.e. a group of people working together to build a product. Creating a reliable development environment for a team can be a PITA. That's why Vagrant, and more recently Docker, gained a lot of traction. People could use Nix to solve the same problem, like ris describes at https://news.ycombinator.com/item?id=10050681
> but everyone can't use their own dependency management system.
This is untrue. Different disciplines use different tools for dependency management and it's not clear to me that the world is crying out for a unification here. Golang developers use one, Nim developers use another. Java developers have different requirements still.
Let's look at a pair of closely related langauges, Clojure and ClojureScript. While we might want a uniform method for DECLARING dependencies, the specific mechanisms used to fetch those dependencies may (and possibly should?) be different.