LiveSplitOne VS Splitter

https://one.livesplit.org livesplit in your browser

Sounds puzzling. Do you know about the browser version of Livesplit? Maybe that would work better for you.

If you download LiveSplit from the official site https://livesplit.org/ and get a zip folder (that you have to extract) there's absolutely no risk. You could also try https://one.livesplit.org/ (LiveSplit One) that doesn't even install anything on your computer, just runs entirely in a browser

Livesplit isn't a virus (https://twitter.com/wooferzfg/status/1300559588819902469?lang=en). However, it's a .exe, so you might not be able to run it on Mac products. You could use Livesplit One instead https://one.livesplit.org/. To get your Switch onto your computer, you'd need to get a capture card. I honestly don't know which ones work for Macs, so you'd need to do a bit of research.

A Speedrunning Browser Timer

If you have concerns, an alternative is the browser version, https://one.livesplit.org/.

You don't need to build from source afaict since they seem to provide a hosted version of it for you: https://one.livesplit.org/

...I guess one last thing is this program only works on PC, if you have a Mac (or chromebook or whatever) the timer selection is very sparse. Though you do have LiveSplit One that runs in a browser https://one.livesplit.org/

I do use SwiftUI for the Welcome screen that shows on startup which I modeled after the one in Xcode. Sometime in the summer of 2020, on a whim, I had an idea to see what it would take to recreate Xcode's welcome screen in SwiftUI, and less than a day later, I had it complete, and I think it turned out pretty well. I was still supporting macOS Mojave at the time, which doesn't support SwiftUI, but I could just if #available it out without loosing much. Aside from a stray bug that broke it in some macOS update, I'm very satisfied with it. You can check it out on GitHub if you're interested.