Postmark has been working on its Message Streams feature for nearly two years, starting as a concept to improve bulk email sending. The company initially planned to launch the feature in 2019 but shifted focus towards infrastructure updates and the COVID-19 pandemic. Postmark took a slow and steady approach to development, releasing small pieces of the feature every few months and gathering customer feedback. This approach allowed them to adjust their scope and required features as they saw real-world usage, test their messaging and positioning in the real world, create extensive help docs for Day 1 wide availability, and complete the giant project with minimal risk to their business or infrastructure. The Message Streams feature is now available to all Postmark customers by default, with the company continuing its gradual rollout while implementing automated emails to help customers get started.