Fedora, Linux

Get notified of new upstream releases

If you maintain a distribution package, or app bundle, or container image, it’s handy to know when components you use in it have new releases.


There is a really useful service Anitya that resides on release-monitoring.org. It watches almost 20 thousand projects for new releases and notify about them.

I maintain several packages in Fedora and the Fedora Project already makes it really convenient for me. It uses Anitya and opens a new bug against your package every time there is a new upstream release which I close once I update the package. But not every project gives you this service.

I also maintain several apps on Flathub which doesn’t provide such a service (yet). And it’s even more important to know about new upstream releases because besides the apps themselves I also have to maintain their dependencies which are not available in runtimes. Especially Evolution has quite a few of them.

Anitya gives you an API, so you can write your own service that will be checking with Anitya. But I’m a lazy person and why to write something that already exists, right? The Fedora Project has a web app called Fedora Notifications which can send notifications of all sorts of events to your email or IRC. You don’t have to be a Fedora package maintainer or anyhow involved in the Project. All you need is a Fedora account (FAS) to log in.

You pick Email Notifications (or IRC, whichever you prefer), click Create New Filter, then you pick Anything regarding a particular “upstream project” rule, and add projects you want to monitor separated by commas. Then click Add this rule and you’re good to go. This is what my rule for components I maitain in Flathub looks like:

Snímek z 2019-05-03 16-47-04

You’ll be getting notifications of new upstream releases to your email and it’s up to you how you’ll act on them. I typically check what kind of release it is, if there are any security or important bug fixes. I try to release those ASAP. Otherwise I plan them for future app releases and test with them beforehand.

I can imagine that there can be a nice automation built on the top of the Anitya API. If it detects a new release, it updates the manifest, triggers a build, and sends you info how it went. Maybe one day 🙂


Fedora in Fediverse


I really like how Fediverse is shaping up and its federation is starting to make sense to me. It’s not federation for the sake of federation and running different instances of the same service, but about variety of different services that focus on different things, cater different users and yet being to able to talk to each other.

There is Mastodon for microblogging, Friendica for a Facebook-style social network, PeerTube for videos, PixelFed for pictures, Nextcloud Social for making a social network out of your private cloud etc.

The number of users is also growing, it’s already in millions, so it’s becoming an interesting platform for promotion. There are quite a few open source projects already present: GNOME, KDE, openSUSE, Ubuntu, Nextcloud, Debian, F-Droid… And I’ve seen quite a few Fedora contributors scattered across different instances.

So I was like why not to have a Fedora instance there. That’s where Fedora contributors and enthusiasts can have their fediverse homes and create a community within a community, and where the Project can have official accounts for posting just like on Twitter or Facebook. The Fedora Code of Conduct would be enforced there, so that people can feel safe there.

I think the most suitable service for that would be Mastodon, microblogging is generally the most popular in Fediverse, Mastodon has a very active development and seems to be the most mature. There is also “Mastodon as a Service” hosting called masto.host. The domain could be e.g. fedora.social.

After proposing it on Fedora Discourse and talking to several people I think the best approach would be starting it as a personal initiative and if it gets traction handing it over to the Project. It would mean that I’d have to cover the hosting costs and rely on donations for the time being because that’s what having a social network where you’re not the product that is being sold takes.

But it would all go in vain if there was no demand for it. So I wonder:

  • Would it make you start using Fediverse/Mastodon?
  • Would it make you switch from another instance? (Mastodon allows you to transfer your data)
  • Would you be willing to take a more active role (admin, moderator…)?
  • Would you make a small contribution to help cover costs of running the service?

If you answer yes to any of the questions, let me know. I’d love to know if there is some demand for this or even people willing to help with it.

Fedora, Linux

Better Bluetooth sound quality on Linux

Over a year ago I got my first serious Bluetooth headphones. They worked with Fedora well, they paired, connected, sound was directed to them. Just the sound quality was not overwhelming. I learnt that because of limited bandwidth of Bluetooth a codec with audio compression has to be used. There are quite a few of them to pick from: AAC (very widely supported because it’s the only one iPhone supports, partly freely available), AptX (also very widely supported, but proprietary), AptX-HD (enhanced AptX with a higher bitrate, also proprietary), LDAC (probably the best codec available, highest bitrate, available in Android, supported mostly by Sony devices), MP3 (also possible, but supported by virtually no devices). And also SBC which is a native Bluetooth, first generation compression codec with rather bad sound quality.

My headphones supported SBC, AAC, AptX, AptX-HD, LDAC, so all the advanced codecs. Sadly on Linux it fallbacked to the basic SBC because no other was available for Bluetooth, and headphones for €200 produced rather underwhelming sound. I mostly listen to music on Spotify. Listening to it on my headphones meant transcoding OGG 320 kbps to SBC and losing a lot of sound quality.

Then I recalled that Sony released LDAC as open source in the Android Open Source Project. And they really did because you can find libldac released under Apache 2.0 License there. So it could possibly be made available on Linux, too. Bluez was also able to negotiate LDAC with the end device. What was missing was a plugin for PulseAudio that would utilize the codec and encode the stream into LDAC before sending it over Bluetooth to the headphones.

Today I learnt that such a plugin had been finally created.  And besides LDAC it also supports AAC, AptX, and AptX-HD. Those are patent-protected codecs and the plugin relies on ffmpeg to support them, so it’s not likely they will be available in Fedora any time soon. But libldac is already in Fedora package review and is waiting for the final legal approval. The plugin currently depends on ffmpeg, but if it were made optional, we could at least ship LDAC support by default in Fedora Workstation.

I thought we could also support AAC because its decoder/encoder is already available in Fedora, but I learnt that it only supported the original AAC format while what devices support these days is HE-AAC which is still protected by patents.

Anyway, someone already built packages of both the plugin and libldac and I installed them to test it. And it worked on Fedora 29 Workstation, LDAC was used for Bluetooth stream encoding:


I don’t have bat ears, but I could recognize a difference in sound quality immediately.

If I’m not mistaken it makes Linux the first desktop system to support LDAC. And with support for other codecs it will make it the OS with the best Bluetooth sound quality support because all other systems support only a subset of the list, hence fewer headphones/speakers at their best sound quality.


F29 release parties in Brno and Prague

I’ve been organizing Fedora release parties in Brno since Fedora 15 (2011) and with the great release of Fedora 29 I couldn’t make an exception. With help of Květa Mrštíková, Lenka Čvančarová, and all speakers I organized F29 release parties in Brno (Nov 26) and in Prague (Dec 4).

The Brno one was hosted in Red Hat offices in Brno and all speakers were redhatters. I kicked off the event with a talk on news in F29 Workstation. Then Michal Konečný continued with his experience using Silverblue (OSTree-based Workstation). František Zatloukal talked on his passion – gaming on Fedora. After the recent release of Proton by Valve, there was a lot to talk about. The last talk was delivered by Lukáš Růžička and it was about maybe the biggest feature in Fedora 29 – modularity.

Michal Konečný talking on Silverblue.

The party was attended by 50+ visitors both from Red Hat and local community (mainly students). Besides food for their minds (talks) there was also refreshment and all kinds of Fedora swag.

A break between talks.

Fedora parties in Prague are usually smaller simply because Red Hat doesn’t have a large office there and visitors come from local community. A smaller number of people and a very cozy venue provided by Etnetera creates very informal atmosphere that generates interesting discussions. I must say I enjoyed this release party perhaps the most from all I’ve ever organized.

Christmasy atmosphere for the F29 party in Prague.

I started with a talk on Workstation and since there was no talk on Silverblue I also talked on my experience with it. My talk blended with interesting discussions about related topics and it took over an hour. But I really enjoyed it because it didn’t feel like talking to a silent crowd and some attendees contributed by interesting points and pushed me to clarify some things I talked about. We also had a talk on modularity, this time by Adam Šamalik and František Zatloukal came with me from Brno to talk on gaming on Fedora. I was really looking forward to the talk by Ondřej Koch from the National Library of Technology where they deployed Fedora Workstation on ~200 PCs. Unfortunately he didn’t show up. Then one of the attendees stepped up and gave a talk on how he created a backup solution based on ZFS for a really small municipality in his birth village.

Adam talking on modularity.
And people listening.
Fedora swag in Prague.

The number of attendees was around 25 and again besides talks we also prepared some food refreshment (courtesy of Red Hat) and a small keg of beer (courtesy of Etnetera). Lenka also surprised everyone by a cake for the 15-year anniversary of Fedora Project.

Lenka cutting the cake.

I’d like to thank everyone who helped with the events and Red Hat and Etnetera for providing venues and refreshment.


Fedora Handbook 2018 Released

I finally finished the 2018 edition of Fedora Handbook (aka Fedora Workstation Beginner’s Guide). Just a recap what the handbook is about: it’s a printed handbook that should give enough information to get a user from “knowing nothing about Fedora” to first steps in the system. It’s used as a giveaway at conferences and other events.

The original handbook was written in Czech in 2015 and the English version released last year introduced only cosmetic changes, so even though the handbook has pretty generic info and is not specific to any Fedora release there were quite a lot of changes needed.

I’d especially like to thank Petr Bokoč who suggested a lot of improvements, implemented some of them, and did the proofreading.

The 2017 edition was only translated into Czech and Spanish. I’d like to see more translations this time. If you’d like to translate it into your language, just go ahead, fork the repo, create a directory named after your language code in the “2018” branch, copy the English origin content into it, and start translating. Once you’re done, do a PR. Please stay in the stable 2018 branch and don’t translate the master. Master is a subject of change and shouldn’t be translated.

We provide a script to automatically generate Docbook, HTML, and PDF files. But ideally the outcome should be a quality PDF that is then printed. But that’s not an automatic process. I’m taking care of the English and Czech versions, but other languages would need volunteers to do the typesetting.

We also have a new cover created by Tereza Hlaváčková under supervision of Mairin Duffy.

Snímek z 2018-12-18 16-52-38

Fedora, GNOME, Linux

Fedora at LinuxDays 2018 in Prague

LinuxDays, the biggest Linux event in the Czech Republic, took place at the Faculty of Information Technology of Czech Technical University in Prague. The number of registered attendees was a bit lower this year, it could be caused by municipality and senate elections happening on Fri and Sat, but the number got almost to the 1300 mark anyway.

Besides a busy schedule of talks and workshops the conference also has a pretty large booth area and as every year I organized the Fedora one. I drove by car to Prague with Carlos Soriano and Felipe Borges from the Red Hat desktop team on Saturday morning and we were joined by František Zatloukal (Fedora QA) at the booth.

František and me at the booth.

Our focus for this year was Silverblue and modularity. I prepared one laptop with an external monitor to showcase Silverblue, the atomic version of Fedora Workstation. I must say that the interest of people in Silverblue surprised me. There were even some coming next day saying: “It sounded so cool yesterday and I couldn’t resist and install it when I got home and played with it in the night…” With Silverblue comes distribution of applications in Flatpak and there was a lot of user interest in this direction as well.

Reasons to use Fedora.

I was hoping for more interest in modularity, but people don’t seem to be so aware of it. It doesn’t have the same reach outside the Fedora Project as Flatpak does, it’s not so easy to explain its benefits and use cases. We as a project have to do a better job selling it.

The highlight of Saturday was when one of the sysadmins at National Library of Technology, which is on the same campus, took us to the library to show us public computers where they run Fedora Workstation. It’s 120 computers with over 1000 users (in the last 90 days). Those computers serve a very diverse group of users, from elderly people to computer science students. And they have received very few complaints since they switched from Windows to Fedora. Also they’ve hit almost no problems as sysadmins. They only mentioned one corner case bug in GDM which we promised to look into.

Carlos and Felipe checking out Fedora in the library.

It was also interesting to see the setup. They authenticate users against AD using the SSSD client, mount /home from a remote server using NFS. They enable several GNOME Shell extensions by default: AlternateTab (because of Windows users), Places (to show the Places menu next to Activities)… They also created one custom extension that replaces the “Power Off” button with “Log Out” button in the user menu because users are not supposed to power the computers off. They also create very useful stats of application usage based on “recently-used” XML files that GNOME creates to generate the menu of frequently used applications. All computers are administrated using Ansible scripts.

Default wallpaper with instructions.

The only talk I attended on Saturday was “Why and How I Switched to Flatpak for App Distribution and Development in Sandbox” by Jiří Janoušek who develops Nuvola apps. It was an interesting talk and due to his experience developing and distributing apps on Linux Jiří was able to name and describe all the problems with app distribution on Linux and why Flatpak helps here.

On Sunday, we organized a workshop to teach to build flatpaks. It was the only disappointment of the weekend. Only 3 ppl showed up and none of them didn’t really need to learn to build flatpaks. We’ll have the same workshop at OpenAlt in Brno and if the attendance is also low, we’ll know that workshop primarily for app developers is not a good fit for such conferences.
But it was not a complete waste of time, we discussed some questions around Flatpak and worked on flatpaking applications. The result is GNOME Recorder already available in Flathub and Datovka in the review process.

The event is also a great opportunity to talk to many people from the Czech community and other global FLOSS projects. SUSE has traditionally a lot of people there, there was Xfce, FFMPEG, FreeBSD, Vim, LibreOffice…


Fedora, GNOME, Linux

Story of GNOME Shell Extensions

A long time ago (exactly 10 years ago) it was decided that the the shell for GNOME would be written in JavaScript. GNOME 3 was still looking for its new face, a lot of UI experimentation was taking place, and JavaScript looked like the best candidate for it. Moreover it was a popular language on the web, so barriers to entry for new contributors would be significantly lowered.

When you have the shell written in JavaScript you can very easily patch it and alter its look and behaviour. And that’s what people started doing. Upstream was not very keen to officially support extensions due to their nature: they’re just hot patching the GNOME Shell code. They have virtually unlimited possibilities in changing look and behaviour, but also in introducing instability.

But tweaking the shell became really popular. Why wouldn’t it? You can tweak your desktop by simply clicking buttons in your browser. No recompilations, no restarts. So extensions.gnome.org was introduced.

The number of available extensions grew to hundreds and instability some of them occasionally introduced seemed like a fair price for the unlimited tweakability. In the end when the Shell crashed it was just a blink. Xorg held up the session with opened clients, the Shell/Mutter was restarted and the show could go on.

In 2016 GNOME switches to Wayland by default. No Xorg and also nothing to hold up the session with opened clients when the Shell crashes. There is only Mutter as a Wayland compositor, but unfortunately it runs in the same process as GNOME Shell (a decision also made 10 years ago when it also looked like a good idea). If the Shell goes down, so does Mutter. Suddenly harmless blinks became desktop crashes with losing all unsaved data in opened applications.

I read user feedback and problems users are having with Fedora Workstation (and Linux desktop in general) a lot on the Internet. And desktop crashes caused by GS extensions are by far the most frequent problem I’ve seen recently. I read stories like “I upgraded my Fedora to 28 and suddenly my desktop crashes 5 times a day. I can’t take it any more and I’m out of ideas” on daily basis. If someone doesn’t step in and say: “Hey, do you have any GS extensions installed? If so, disable them and see if it keeps crashing. The extensions are not harmless, any error in them or incompatibility between them and the current version of GS can take the whole desktop down”, users usually leave with the experience of unstable Linux desktop. It hurts our reputation really badly.

Are there any ways to fix or at least improve the situation? Certainly:

  1. Extensions used to be disabled when the Shell crashed hard (couldn’t be restarted). Since on Wayland it’s the result of every crash, we should do that after every GS crash. And when the user goes back to GNOME Tweak Tool to enable the extensions again, she/he should be told that it was mostly likely one of the 3rd party extensions that made the desktop crash, and she/he should be careful when enabling them.
  2. Decoupling GNOME Shell and Mutter or/and other steps that would bring back the same behaviour like on Xorg: GS crash would not take everything down. This would require major changes in the architecture and a lot of work and GNOME Shell and Mutter developer community has already a lot on their plates.
  3. Discontinuing the unlimited extensions, introducing a limited API they can use instead of hot patching the GS code itself. This would be a very unpopular step because it’d mean that many of the existing extensions would be impossible to implement again. But it may become inevitable in the future.