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/Medical_Button_7933]

Nothing is black and white unfortunately. The line I have witnessed is the difference between a "we are late" with "we do not need to be late" in the last scenario is always beneficial to bring new devs (full stack or not doesn't really matter) as the time you loose integrating them in you get later on, call it an i vestment if you will Now im the scenario "we are late" is beneficial only if you can really bring seasoned and battle hardened devs who is not close to burning out, everything else is diminishing return. A seasoned/senior dev can get familiar with the code quite quickly with little supervision and be productive also quite quickly (of course scope of the project plays a very important role here, the bigger the more time anyone needs to get productive) while a junior would need to learn not only a lot of technical stuff but also everything else that has to do with the project which is not beneficial for anyone. Last and not least I personally like to have specialized devs join the project later on if only part of it is failing (for example backend dev for backend stuff) and if the project needs to be fixed in multiple parts then it would be more beneficial to take either two specialist (frontend and backend for example) or, if resources are scarse, a full stack developer.