I get a curl error 28 - connection timed out. Sometimes it asks for a token first. I’ve tried with my personal github token. No dice.
I also tried with the squizlabs/php_codesniffer removed from the composer json because that seemed to be the hangup. It just hung up on another codesniffer from another source.
Is there a way to download a matomo with the developer files already in place? The issues I’m having with composer (wrestling for 3 days) are a huge hangup. And I need to do some development in matomo.
Is there maybe some firewall in your internet connection that is blocking this specific request?
You could try composer install --no-dev or not only remove the "squizlabs/php_codesniffer": "^3.5", line, but also the composer.lock file to not install php_codesniffer at all.
I am not sure what the alternative is. If you can’t access the packagist repostory composer uses, you could try using a mirror of it: https://packagist.org/mirrors
But without access to download php libraries, it is hard to set up a development environment.
This makes Matomo dev hard for users in enterprise environments behind firewalls. I’d have the same problem with a mirror–against company policy. It’s the idea of a VM going out to a bunch of sites and bringing data back, rather than a single package that can be scanned.