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Status update, March 2019

I guess it’s already status update time! This month has been pretty busy for me because I’ve moved to Finland to work for Intel1. It’s been really great so far, I’ve been working on automating HDMI/DisplayPort audio testing using Google’s Chamelium. I’ve had plenty of fun talking to the DisplayPort receiver via I²C and writing C & Python code to automate everything!

One of the first patches I wrote this month were for lists.sr.ht. I added a little DKIM authentication indicator to make sure messages come from where they say they come from. I’d like to add support for DMARC (which allows domain names to e.g. require DKIM for all of their outgoing e-mails) and PGP next.

A DKIM indicator

Adding this indicator has made us investigate some DKIM failures, so I’ve also been working on go-dkim, my Go library for DKIM. go-dkim now includes a milter (a Postfix mail filter, via go-milter) that signs and verifies e-mails. I’ve started a go-dmarc project to retrieve DMARC policies.

Continuing on Go e-mail stuff, maddy has received major updates. foxcpp has been rewriting a lot of the codebase and they’ve been working on go-imap-sql, a SQL backend now used by default by maddy. E-mail servers are complicated and it’s not easy to make them (1) user-friendly and (2) have secure defaults. But it’s an interesting problem and we’ll definitely try our best. maddy is now able to accept new features and already has gained support for local authentication. Thanks foxcpp for your work!

What would be a status update without some Wayland news? Martin Peres has convinced me that wlroots would benefit a lot from having DRM overlay planes support. Those would enable the compositor to completely skip compositing in some cases: for instance if the compositor puts the web browser you’re currently using on a plane, it means that it hands over the web browser’s buffers directly to the graphics driver, without an intermediate copy and without waking up the GPU (this is called direct scan-out). That should improve battery performance significantly!2

So in order to get this feature in wlroots, we first need to revamp the wlroots API. I’ve started sending a few patches to make it possible. One of the first steps is adding support for direct scan-out for fullscreen windows only (then we’ll be able to extend this to non-fullscreen windows via overlay planes).

Earlier this month I’ve also worked on an output management protocol for Wayland, but this deserves its own blog post so I’ll leave it out of this status update.

That’s all for this month, thanks for reading!


  1. The opinions expressed on this site are mine alone and do not necessarily reflect the opinions or strategies of Intel Corporation or its worldwide subsidiaries. ↩︎

  2. In fact many phones take advantage of overlay planes, for instance Android ↩︎


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