November 2016 Summaries

We are announcing a new, lower-priced tier for our transactional email services. The new tier offers $1.25 per 1,000 emails at 200,000+ credits, reducing the price from $1.50 to $1.25 for users who purchase between 200,000 and 500,000 credits regularly. We have also redesigned our pricing page to provide a more user-friendly experience, allowing customers to input their email volume and receive an effective monthly cost estimate at each tier. The changes take effect on December 13, 2017, and existing customers are encouraged to transition to a Monthly Plan, which offers additional flexibility and savings opportunities.

The Postmark team has released enhancements to their bounce webhook feature, including the addition of "From" and "ServerID" fields in the webhook data, allowing for easier troubleshooting of bounce issues. These improvements aim to provide more flexibility in responding to bounces, while also planning future releases such as a delivery event webhook. The company is interested in hearing from customers about their use cases for webhooks, inviting them to share feedback via [email protected].

We recently released a new enhancement to email sending called “Link Tracking” which provides insights into how recipients interact with emails, including preferred browsers and locations. To achieve this, we built a reliable, fast, and secure system that uses a geo-distributed approach, making it highly available even under circumstances where other parts of the Postmark infrastructure may be experiencing delays or issues. The system uses full-time HTTPS to prevent eavesdropping and relies on HMACs to validate requests. Each tracked link is completely standalone, minimizing latency and ensuring strong consistency. We've deployed Link Routers in pairs across three regions worldwide, capable of handling approximately 1,900 requests per second, with the ability to easily add capacity as usage grows.

Postmark provides webhooks for bounces, inbound messages, and open tracking events in the form of HTTP POSTs in well-formatted JSON to the specified URL. Webhooks allow users to receive notifications and data as triggering events occur without having to make API calls. The JSON format for bounce and spam complaint notifications includes fields such as ID, Type, Name, Tag, MessageID, Description, Email, BouncedAt, DumpAvailable, Inactive, CanActivate, Subject, and more. For inbound messages, the received JSON contains information about the sender's email address, recipient's name and email address, message content, attachments, and other details. The open tracking webhook pushes notifications with data such as client type, OS environment, and user agent information when an email is opened. Delivery webhooks provide real-time notifications for successful delivery of emails sent through Postmark. To test webhooks, users can use RequestBin or cURL to receive and process the data received at their URL(s). Security measures include validating incoming requests against JSON schema and only allowing HTTP POST method usage. An example application demonstrating how to receive, process, and display Postmark's webhooks is available on GitHub.