Sqreen was a great product for startups. Unfortunately acquired by the Datadog. Product was never fully integrated into their offerings and there is no such alternative.
Hey I'm an engineer who worked at Sqreen and now Datadog. What kind of feature is still missing in Datadog ASM? To my knowledge everything is there except managing CSP and security headers now.
Ah yes, we are still missing RASP support on ruby, but this should come out in the next 3-6 months. Everything else should be supported though (In App WAF, playbook, user monitoring etc)