Polar

Polar is a developer-first billing and monetization platform built for AI companies and SaaS teams, acting as a global Merchant of Record so teams skip tax, VAT, and fraud setup. Ships Next.js, BetterAuth, and TypeScript adapters plus SDKs for Python and JS, event-based usage billing, subscription tiers with feature benefits, webhooks, and a secure hosted checkout. Priced at 4% + $0.40 per transaction with no monthly fees — aimed at founders who want Stripe-like flexibility without building compliance plumbing.