> More troublingly, performance has not improved in CI at the same pace as on developer machines—it’s usually a lot slower to build our app in CI than it is to do it locally on my M1 laptop.

While some of the other comments around optimizing CI pipelines are solid, this whole thing seems to be due to having CI running on servers that are -worse- than a laptop. Isn't that wild? Servers weaker than laptops. Not even desktops or workstations. LAPTOPS.

And they are, because they're just cloud instances. And most cloud instances... are not fast.

Consider the idea that you could run your CI runner on an M1 laptop if you so choose to. Setting up a self-hosted GH Actions runner (for example) is quite straightforward. Doesn't even need to be an internet-facing machine, it can be a spare machine sitting at home/office. $600 will get you a Mac mini with an M2 CPU and super-fast SSD; everything will build faster than it ever could on any generic CI build server.