I was recently introduced to Cypress https://www.cypress.io. It's a testing tool that can, amongst other things, run browser automation. One of it's features is that it 'does not use Selenium.' :-)

There's also the command line method, using wp-cli: wp core download --skip-content --force Read more about wp-cli core command

I have found Code Review, on the Stack Exchange network, useful for this sort of thing. Here's the current code reviews for PHP