We’re Making Email More Modern With JMAP

The specifications for JMAP have been published by the Internet Engineering Task Force (IETF), marking a big victory for email tools now and in the future.


Fastmail engineers have been working for the past five years to bring JMAP technology to developers and customers. We’re proud to announce that RFC 8620, published on July 18th, and RFC 8621, published on August 13th, have introduced JMAP to the world!

These documents have been reviewed and refined by the Internet Engineering Task Force (IETF), a trusted publisher of high quality, fully open technical specifications.

Open standards drive the power of the internet

Open standards make it possible for you to keep connected across your services. Without them, companies build proprietary protocols that can lock you into a single provider. We believe you deserve more choices for email providers, and control so you can change providers as you please. We also want a more level playing field so more email innovation can occur.

Open standards allow you to select tools from different providers, and have them work together. In our work to make email fast, efficient, and fair, we contribute to improving open standards for all the services that we use.

Creating standards that make the internet work

It was clear to our team that we could offer more to email customers if we had a protocol aligned with how people use email today. As champions of open standards, we wanted that technology to be available to customers using any email client. The existing open email protocol, IMAP, was designed before mobile devices were common and makes long-lived, inefficient connections. You can learn more about our reasoning for replacing IMAP at the JMAP website under “Why is this needed?”.

In 2014, we announced our work on JMAP, a new protocol that leveraged existing standards to make it easier for developers to work with email on the web and in modern programming environments. JMAP also lets us, as well as other email developers, create more features for customers.

The primary author of the specification is Neil Jenkins, Director and User Experience Architect at Fastmail, and the co-author is Chris Newman, Principal Engineer at Oracle. Our CEO, Bron Gondwana, worked to shepherd the specification through the IETF as co-chair of the JMAP working group.

“With JMAP we want to spur email innovation by making the best protocol for email be an open standard,” says Jenkins. “This work is based on years of real-world experimentation at Fastmail and conversations with developers at other major email providers and client teams. The result is a protocol that’s much easier for developers to work with, makes efficient use of network resources, and allows a richer experience for mobile users.”

A victory five years in the making

On July 18th, 2019, after months of knowing we were on the home straight, we could finally bring out the champagne glasses. RFC 8620 was published, introducing a model for efficient data synchronization. On August 13th, 2019, RFC 8621 took what IMAP does for email and made it simpler, faster, and more extendable using the JMAP framework.

At IETF, experts from all over the world generate new specifications. Whether from big tech companies, universities, or other interested parties, we work together as equals to create high-quality internet standards. For Fastmail engineers, we see IETF’s acceptance and support of JMAP as a tremendous achievement, demonstrating what big ideas and hard work can do.

What this means for you

Fastmail and Topicbox customers are already benefiting from JMAP. It backs our web interface and apps, giving customers a reliable and streamlined experience, with more enhancements coming soon.

Beyond that, we hope that something speaks to you in learning about the international cooperation, community, and inclusion that open standards foster. Through knowing our customers, it’s clear to us that many email users today are uncomfortable with the control that some providers are asking you to give up.

What you need and expect is private, secure email, which you can always access, and that you fully own. However, proprietary tools make these core concepts fragile. Open standards keep improving based on new technologies and consumer needs, giving people back the power and control that they expect when using email.

Specifically, JMAP makes massive email archives ready for you remotely nearly as fast if you had the data already on your device. On mobile, instead of waiting for a refresh, you get instant push notifications when the server receives an email. Plus, JMAP makes it easy to add a subset of information from a mailbox or calendar to a new service. Developers can build on top of existing services, creating more tools and conveniences for customers everywhere.

How to use JMAP right now

If you’ve been thinking about developing for email, you can start working with JMAP today! Developers can learn more about implementation at jmap.io.

Development releases of the open-source Cyrus IMAP server have JMAP support already, built and maintained by Fastmail engineers. Set up a test mail server and monitor both ends of the connection.

The Fastmail apps and web interface are also using JMAP already, and we have an invitation-only developer beta underway. If you’re interested in using Fastmail for your JMAP development, please subscribe to our developer public beta group on Topicbox. We’ll contact you as we add more developers to our beta.

We are working hard to grow adoption of JMAP by other providers, too. In the future, it will be available to more people as email clients, and servers made by other companies and developers add support.

To see the speed of the future, try Fastmail today. Start a free trial and download our mobile apps during your trial.

We hope you enjoy your experience as part of the next wave of email innovation!

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