AI has become part of how most software gets written, and Stalwart is no exception. But “we use AI” has become such a vague statement that it says almost nothing. So this post is the specific version: where AI measurably helps us, where we deliberately keep it out of the codebase, and why a server designed to run in large clusters still gets its architecture written by hand.
Today we released Stalwart v0.16.10, a release that closes every single open bug report we have on record: both the legacy issues on GitHub and the reports filed through our new support portal. With the tracker clear of bugs, we want to share where Stalwart stands today and what is left before we ship version 1.0.
In professional cycling, the concept of marginal gains became famous through Team Sky. Rather than chasing dramatic breakthroughs, they focused on making hundreds of small improvements: slightly better bike fit, marginally lighter components, improved sleep, cleaner nutrition. None of these changes mattered much on their own, but together they reshaped performance—and helped dominate the sport for years.
Software systems, especially large distributed ones, work much the same way. Rarely does a single feature transform everything overnight. More often, real progress comes from careful attention to small details: shaving latency here, reducing contention there, simplifying a hot path, rethinking a data structure.
Stalwart v0.15 is very much a release in this spirit. It does not introduce a long list of headline features. Instead, it is the result of revisiting core subsystems—spam filtering, search, storage, and data access—and making many targeted improvements that, together, have a significant impact on performance, reliability, and usability.
We are excited to announce the release of Stalwart Mail Server v0.5.0. As we approach the end of the year, this significant update marks a major advancement in our journey to provide a robust, efficient, and versatile mail server solution. This latest version incorporates a range of performance enhancements, storage layer improvements, and new features, designed to elevate your email server experience.
