I never had huge issues but I don't use XCode nor I develop things that are too CPU bound.
I have 16GB of RAM and a SSD inside a Macbook Pro 13" Mid 2012.
I love(d) VSCode but I switched back to Sublime Text 3 which is noticeably faster. The only thing kinda slow in Sublime Text (which is faster in VSCode because it uses a Rust binary) is the search inside the IDE.
I'm still on High Sierra not because of performance concerns but because I haven't bothered upgrading after I read some conflicting reports about it, I'm waiting for a stabler version (same with my phone and iOS 13).
I think 2020 will likely be the last year (or maybe not) of this computer. I'm curios to see if they release MB Pros 13" with a decent keyboard in June or something.
Unfortunately this is probably not much of help because you can't upgrade your MB Air.
I've never used Node but the NPM and JS ecosystem aren't super conservative on resources, I had a really fast feedback cycle when I was developing a web app in Go (though changing stack instead of changing hardware might be not a good idea :D).
Understand if you can change any variables in the hardware, if you can't you might need to use other tools. Look for tools that are native and/or compiled and which use less resources in general.
ps. the Rust based grep tool is github.com/BurntSushi/ripgrep which in my opinion is a game changer if you grep a lot in the command line like I do :D
Thanks, rhymes! I'm actually looking into playing with variables/configs, looks like it's inevitable. And I like Sublime too, it's really much faster 👍 I'd rolled back to High Sierra, not sure it will help, but who knows.
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