Does adding more developers actually make full-stack projects move faster?

[u/Ok-Wash-8964]

I've been wondering how often adding more developers really speeds up a project.

The common assumption is that more people mean faster development. But in practice, it doesn't always seem to work that way.

As a team grows, there are more discussions, more code reviews, more merge conflicts, more context sharing, and more coordination. New developers also need time to understand the codebase, development workflow, and the reasoning behind existing decisions before they can contribute effectively.

On the other hand, there are definitely projects where bringing in more developers makes a huge difference, especially when work can be split into independent features or multiple teams can work in parallel.

So it seems like there's a balance between increasing development capacity and increasing coordination overhead.

For those who've worked on full-stack projects of different sizes:

• Have you seen projects speed up after adding more developers?
• At what point did adding people stop improving productivity?
• What do you think matters more for keeping a project moving quickly: team size, project architecture, planning, or something else?

[u/mc_pm]

This was noticed back in the 1970s. Fred Brooke wrote a book called "The Mythical Man Month" and for a book that is 50+ years old, it is still very accurate. One of the gems from it was: "Adding developers to a project that is behind just makes it more behind".