Postmark alternative for startups

There are roughly 25-35 serious transactional email providers competing for startup attention, but most fall into two camps: over-engineered enterprise solutions (SendGrid, Postmark themselves) or barebones commodity players missing critical features. The actual pain point isn't email sending—it's that startups overpay for monitoring, analytics, and support they don't use yet, while simultaneously getting locked into contracts that don't match their growth trajectory. The gap exists in the middle: providers offering 90% of Postmark's reliability at 40% of the cost, with transparent usage-based pricing and zero onboarding friction. A vibecoder entering this space should obsess over three things: (1) sub-second setup—templates, API key generation, and first send in under 10 minutes, (2) honest pricing with no surprise tiers or hidden fees based on email volume, and (3) exceptional onboarding documentation that assumes the founder is technically capable but time-poor. The winners won't be those with fancier features; they'll be the ones who make the switching cost from Postmark negligible and the first month experience delightful enough that founders don't have bandwidth to reconsider.