Hi,
I'm maintainer of dragonbe/hibp, a composer package to validate passwords against the Have I been pwned? API service to see if a provided password was already used in a breach.
Today (April 5, 2019) Symfony announced they integrate the same service as a validation component in their 4.3 version and I see this as a good way to offer this functionality as part of the framework toolkit. Too bad they're not using my service though.
So I want to propose a validation rule to check provided passwords against HIBP API.