With the new hotness that is Github Actions taking off, some of you with existing CI workflows have likely wondered if you should migrate. I recently investigated this, and while I'll spare you all the nuanced details, I will share the simple litmus test I came up with for picking between the two:
Does your team use more than 2,000 minutes per user, per month on CI?
If you answered Yes to the question above, then CircleCI is still the more valuable choice for your CI workflows, as it provides more robust computing resources & optimization methods that Github Actions doesn't.
For anything less than 2,000 minutes/user/month, go with Github Actions.