Forum OpenACS Development: OpenACS permissions system as model for new system?

My apologies for being slightly off-topic...

I'm somewhat familiar with OpenACS's permissions system, having worked with it some about 10 years ago. I remember being impressed with the flexibility it offered.

Now I'm working on an Elixir website that could use some CMS-like permissions and I am considering porting over the OACS PostgreSQL permissions code as a starting point. However, I vaguely remember that some folks had performance issues with OACS permissions and resorted to checking group membership as a surrogate for permissions and/or granting access to "pages" vs. objects.

Would y'all recommend OACS data model as a good starting point for a permissions system? Are there any other (maybe more "modern") permissions/ACL systems I should look to for guidance instead?