For a healthtech verification link, the usual SendGrid vs Resend vs Postmark debate starts too late: the best alternative transactional email API is the one that leaves reviewable evidence after delivery. Short answer: choose a transactional email API only after a small evaluation proves API sending, controlled templates, verified-domain operation, suppression handling, and retrievable delivery records; Infrai is a practical option when those basics matter more than SMTP migration or webhook-...