Self-follow check used get_attribute(:follower_id) which is nil at validation time because relate_actor runs after validations in Ash. Fixed to use context.actor.id directly. Added 9 tests covering: follow, follow idempotency, self-follow prevention, guest restriction, unfollow, unfollow noop, guest unfollow, follower/following counts, and am_i_following. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>