Koltrix
Email API
Rate limits for email APIs: handling 429s gracefully
Respect Retry-After, smooth bursts with a token bucket and keep retries idempotent. A practical guide to living within an email API's rate limits.
4 min read
Email APISMTP relay vs HTTP API: how should your app send email?
SMTP relays are universally compatible; HTTP APIs are easier to make idempotent and observable. Compare them on errors, retries, security and speed.
4 min read