This is ready for testing on crust.piefed.social. I've made two testing posts in the testing community

• https://crust.piefed.social/c/test/p/74625/test-poll
• https://crust.piefed.social/c/test/p/74626/test-event

In the API they show up as extra data on a post. For example here https://crust.piefed.social/api/alpha/post/list?community_name=test@crust.piefed.social you'll see this for event posts:

and this for poll posts:

Other types of post will not have that data present, not even as an empty object or null. Let me know if that causes you problems.

As always, the full API spec is at https://crust.piefed.social/api/alpha/swagger including how to add or edit those types of post. It's the same data structure as getting a post.