Planet GNOME

The Wayland core protocol has described surface state updates the same way since the beginning: requests modify pending state, commits either apply that state immediately or cache it into the parent for synchronized subsurfaces. Compositors implemented this model faithfully. Then things changed.

Buffer Readiness and Compositor Deviation

The problem emerged from GPU work timing. When a client commits a surface with a buffer, that buffer might still have GPU rendering in progress. If the compositor applies the commit immediately, it would display incomplete content—glitches. If the compositor submits its own GPU work with a dependency on the unfinished client work, it risks missing the deadlines for the next display refresh cycles and even worse stalling in some edge cases.

To get predictable timing, the compositor needs to defer applying commits until the GPU work finishes. This requires tracking readiness constraints on committed state.

Mutter was the first compositor to address this by implementing constraints and dependency tracking of content updates internally. Instead of immediately applying or caching commits, Mutter queued the changes in what we now call content updates, and only applied them when ready. Critically, this was an internal implementation detail. From the client’s perspective, the protocol semantics remained unchanged. Mutter had deviated from the implementation model implied by the specification while maintaining the observable behavior.

New Protocols on Unstable Foundations

When we wanted better frame timing control and a proper FIFO presentation modes on Wayland, we suddenly required explicit queuing of content updates to describe the behavior of the protocols. You can’t implement FIFO and scheduling of content updates without a queue, so both the fifo and commit-timing protocols were designed around the assumption that compositors maintain per-surface queues of content updates.

These protocols were implemented in compositors on top of their internal queue-based architectures, and added to wayland-protocols. But the core protocol specification was never updated. It still described the old “apply or cache into parent state” model that has no notion of content updates, and per-surface queues.

We now had a situation where the core protocol described one model, extension protocols assumed a different model, and compositors implemented something that sort of bridged both.

Implementation and Theory

That situation is not ideal: If the internal implementation follows the design which the core protocol implies, you can’t deal properly with pending client GPU work, and you can’t properly implement the latest timing protocols. To understand and implement the per-surface queue model, you would have to read a whole bunch of discussions, and most likely an implementation such as the one in mutter. The implementations in compositors also evolved organically, making them more complex than they actually have to be. To make matter worse, we also lacked a shared vocabulary for discussing the behavior.

The obvious solution to this is specifying a general model of the per-surface content update queues in the core protocol. Easier said than done though. Coming up with a model that is sufficient to describe the new behavior while also being compatible with the old behavior when no constraints on content updates defer their application was harder than I expected.

Together with Julian Orth, we managed to change the Wayland core protocol, and I wrote documentation about the system.

Recently Pekka Paalanen and Julian Orth reviewed the work, which allowed it to land. The updated and improved Wayland book should get deployed soon, as well.

The end result is that if you ever have to write a Wayland compositor, one of the trickier parts to get right should now be almost trivial. Implement the rules as specified, and things should just work. Edge cases are handled by the general rules rather than requiring special knowledge.

Before the managed data types extension to WebAssembly was incorporated in the standard, there was a huge debate about type equality. The end result is that if you have two types in a Wasm module that look the same, like this:

(type $t (struct i32)) (type $u (struct i32))

Then they are for all intents and purposes equivalent. When a Wasm implementation loads up a module, it has to partition the module’s types into equivalence classes. When the Wasm program references a given type by name, as in (struct.get $t 0) which would get the first field of type $t, it maps $t to the equivalence class containing $t and $u. See the spec, for more details.

This is a form of structural type equality. Sometimes this is what you want. But not always! Sometimes you want nominal types, in which no type declaration is equivalent to any other. WebAssembly doesn’t have that, but it has something close: recursive type groups. In fact, the type declarations above are equivalent to these:

(rec (type $t (struct i32))) (rec (type $u (struct i32)))

Which is to say, each type is in a group containing just itself. One thing that this allows is self-recursion, as in:

(type $succ (struct (ref null $succ)))

Here the struct’s field is itself a reference to a $succ struct, or null (because it’s ref null and not just ref).

To allow for mutual recursion between types, you put them in the same rec group, instead of each having its own:

(rec (type $t (struct i32)) (type $u (struct i32)))

Between $t and $u we don’t have mutual recursion though, so why bother? Well rec groups have another role, which is that they are the unit of structural type equivalence. In this case, types $t and $u are not in the same equivalence class, because they are part of the same rec group. Again, see the spec.

Within a Wasm module, rec gives you an approximation of nominal typing. But what about between modules? Let’s imagine that $t carries important capabilities, and you don’t want another module to be able to forge those capabilities. In this case, rec is not enough: the other module could define an equivalent rec group, construct a $t, and pass it to our module; because of isorecursive type equality, this would work just fine. What to do?

cursèd nominal typing

I said before that Wasm doesn’t have nominal types. That was true in the past, but no more! The nominal typing proposal was incorporated in the standard last July. Its vocabulary is a bit odd, though. You have to define your data types with the tag keyword:

(tag $v (param $secret i32))

Syntactically, these data types are a bit odd: you have to declare fields using param instead of field and you don’t have to wrap the fields in struct.

They also omit some features relative to isorecursive structs, namely subtyping and mutability. However, sometimes subtyping is not necessary, and one can always assignment-convert mutable fields, wrapping them in mutable structs as needed.

To construct a nominally-typed value, the mechanics are somewhat involved; instead of (struct.new $t (i32.const 42)), you use throw:

(block $b (result (ref exn)) (try_table (catch_all_ref $b) (throw $v (i32.const 42))) (unreachable))

Of course, as this is a new proposal, we don’t yet have precise type information on the Wasm side; the new instance instead is returned as the top type for nominally-typed values, exn.

To check if a value is a $v, you need to write a bit of code:

(func $is-v? (param $x (ref exn)) (result i32) (block $yep (result (ref exn)) (block $nope (try_table (catch_ref $v $yep) (catch_all $nope) (throw_ref (local.get $x)))) (return (i32.const 0))) (return (i32.const 1)))

Finally, field access is a bit odd; unlike structs which have struct.get, nominal types receive all their values via a catch handler.

(func $v-fields (param $x (ref exn)) (result i32) (try_table (catch $v 0) (throw_ref (local.get $x))) (unreachable))

Here, the 0 in the (catch $v 0) refers to the function call itself: all fields of $v get returned from the function call. In this case there’s only one, othewise a get-fields function would return multiple values. Happily, this accessor preserves type safety: if $x is not actually $v, an exception will be thrown.

Now, sometimes you want to be quite strict about your nominal type identities; in that case, just define your tag in a module and don’t export it. But if you want to enable composition in a principled way, not just subject to the randomness of whether another module happens to implement a type structurally the same as your own, the nominal typing proposal also gives a preview of type imports. The facility is direct: you simply export your tag from your module, and allow other modules to import it. Everything will work as expected!

fin

Friends, as I am sure is abundantly clear, this is a troll post :) It’s not wrong, though! All of the facilities for nominally-typed structs without subtyping or field mutability are present in the exception-handling proposal.

The context for this work was that I was updating Hoot to use the newer version of Wasm exception handling, instead of the pre-standardization version. It was a nice change, but as it introduces the exnref type, it does open the door to some funny shenanigans, and I find it hilarious that the committee has been hemming and hawwing about type imports for 7 years and then goes and ships it in this backward kind of way.

Next up, exception support in Wastrel, as soon as I can figure out where to allocate type tags for this new nominal typing facility. Onwards and upwards!

Good evening. Let’s talk about free trade!

Last time, we discussed Marc-William Palen’s Pax Economica, which looks at how the cause of free trade was taken up by a motley crew of anti-imperialists, internationalists, pacifists, marxists, and classical liberals in the nineteenth century. Protectionism was the prerogative of empire—only available to those with a navy—and it so it makes sense that idealists might support “peace through trade”. So how did free trade go from a cause of the “another world is possible” crowd to the halls of the WTO? Did we leftists catch a case of buyer’s remorse, or did the goods delivered simply not correspond to the order?

To make an attempt at an answer, we need more history. From the acknowledgements of Quinn Slobodian’s Globalists:

This book is a long-simmering product of the Seattle protests against the World Trade Organization in 1999. I was part of a generation that came of age after the Cold War's end. We became adolescents in the midst of talk of globalization and the End of History. In the more hyperactive versions of this talk, we were made to think that nations were over and the one indisputable bond uniting humanity was the global economy. Seattle was a moment when we started to make collective sense of what was going on and take back the story line. I did not make the trip north from Portland but many of my friends and acquaintances did, painting giant papier-mâché fists red to strap to backpacks and coming back with takes of zip ties and pepper spray, nights in jail, and encounters with police—tales they spun into war stories and theses. This book is an apology for not being there and an attempt to rediscover in words what the concept was that they went there to fight.

Slobodian’s approach is to pull on the thread that centers around the WTO itself. He ends up identifying what he calls the “Geneva School” of neoliberalism: from Mise’s circle in Vienna, to the International Chamber of Commerce in Paris, to the Hayek-inspired Mont Pèlerin Society, to Petersmann of the WTO precursor GATT organization, Röpke of the Geneva Graduate Institute of International Studies, and their lesser successors of the 1970s and 1980s.

The thesis that Slobodian ends up drawing is that neoliberalism is not actually a laissez-faire fundamentalism, but rather an ideology that placed the value of free-flowing commerce above everything else: above democracy, above sovereignty, above peace, and that as such it actually requires active instutional design to protect commerce from the dangers of, say, hard-won gains by working people in one country (Austria, 1927), expropriation of foreign-owned plantations in favor of landless peasants (Guatemala, 1952), internal redistribution within countries transitioning out of minority rule (South Africa, 1996), decolonization (1945-1975 or so), or just the election of a moderate socialist at the ballot box (Chile, 1971).

Now, dear reader, I admit to the conceit that if you are reading this, probably you are a leftist also, and if not, at least you are interested in understanding how it is that we think, with what baubles do we populate our mental attics, that sort of thing. Well, friend, you know that by the time we get to Chile and Allende we are stomping and clapping our hands and shouting in an extasy of indignant sectarian righteousness. And that therefore should we invoke the spectre of neoliberalism, it is with the deepest of disgust and disdain: this project and all it stands for is against me and mine. I hate it like I hated Henry Kissinger, which is to say, a lot, viscerally, it hurts now to think of it, rest in piss you bastard.

two theologies

And yet, I’m still left wondering what became of the odd alliance of Marx with Manchester liberalism. Palen’s Pax Economica continues to sketch a thin line through the twentieth century, focusing on showing the continued presence of commercial-peace exponents despite it not turning out to be our century. But the rightward turn of the main contingent of free-trade supporters is not explained. I have an idea about how it is that this happened; it is anything but scholarly, but here we go.

Let us take out our coarsest brush to paint a crude story: the 19th century begins in the wake of the American and French revolutions, making the third estate and the bourgeoisie together the revolutionary actors of history. It was a time in which “we” could imagine organizing society in different ways, the age of the utopian imaginary, but overlaid with the structures of the old, old money, old land ownership, revanchist monarchs, old power, old empire. In this context, Cobden’s Anti-Corn Law League was insurgent, heterodox, asking for a specific political change with the goal of making life on earth better for the masses. Free trade was a means to an end. Not all Cobdenites had the same ends, but Marx and Manchester both did have ends, and they happened to coincide in the means.

Come the close of the Great War in 1918, times have changed. The bourgeoisie have replaced the nobility as the incumbent power, and those erstwhile bourgeois campaigners now have to choose between idealism and their own interest. But how to choose?

Some bourgeois campaigners will choose a kind of humanist notion of progress; this is the thread traced by Palen, through the Carnegie Endowment for International Peace, the Young Women’s Christian Association, the Haslemere Group, and others.

Some actors are not part of the hegemonic bourgeoisie at all, and so have other interests. The newly independent nations after decolonization have more motive to upend the system than to preserve it; their approach to free trade has both tactical and ideological components. Tactical, in the sense that they wanted access to first-world markets, but also sometimes some protections for their own industries; ideological, in the sense that they often acted in solidarity with other new nations against the dominant powers. In addition to the new nations, the Soviet bloc had its own semi-imperial project, and its own specific set of external threats; we cannot blame them for being tactical either.

And then you have Ludwig von Mises. Slobodian hints at Mises’ youth in the Austro-Hungarian empire, a vast domain of many languages and peoples but united by trade and the order imposed by monarchy. After the war and the breakup of the empire, I can only imagine—and here I am imagining, this is not a well-evidenced conclusion—I imagine he felt a sense of loss. In the inter-war, he holds court as the doyen of the Vienna Chamber of Commerce, trying to put the puzzle pieces back together, to reconstruct the total integration of imperial commerce, but from within Red Vienna. When in 1927, a court decision acquitted a fascist milicia that fired into a crowd, killing a worker and a child, the city went on general strike, and workers burned down the ministry of justice. Police responded violently, killing 89 people and injuring over 1000. Mises was delighted: order was restored.

And now, a parenthesis. I grew up Catholic, in a ordinary kind of way. Then in my early teens, I concluded that if faith meant anything, it has to burn with a kind of fervor; I became an evangelical Catholic, if such is a thing. There were special camps you could go to with intense emotional experiences and people singing together and all of that is God, did you know? Did you know? The feelings attenuated over time but I am a finisher, and so I got confirmed towards the end of high school. I went off to university for physics and stuff and eventually, painfully, agonizingly concluded there was no space for God in the equations.

Losing God was incredibly traumatic for me. Not that I missed, like, the idea of some guy, but as someone who wants things to make sense, to have meaning, to be based on something, anything at all: losing a core value or morality invalidated so many ideas I had about the world and about myself. What is the good life, a life well led? What is true and right in a way that is not contingent on history? I am embarrassed to say that for a while I took the UN declaration of human rights to be axiomatic.

When I think about Mise’s reaction to the 1927 general strike in Vienna, I think about how I scrambled to find something, anything, to replace my faith in God. As the space for God shrank with every advance in science, some chose to identify God with his works, and then to progressively ascribe divine qualities to those works: perhaps commerce is axiomatically Good, and yet ineffable, in the sense that it is Good on its own, and that no mortal act can improve upon it. How else can we interpret Hayek’s relationship with the market except as awe in the presence of the divine?

This is how I have come to understand the neoliberal value system: a monotheism with mammon as godhead. There may be different schools within it, but all of the faithful worship the same when they have to choose between, say, commerce and democracy, commerce and worker’s rights, commerce and environmental regulation, commerce and taxation, commerce and opposition to apartheid. It’s a weird choice of deity. Now that God is dead, one could have chosen anything to take His place, and these guys chose the “global economy”. I would pity them if I still had a proper Christian heart.

means without end

I think that neoliberals made a miscalculation when they concluded that the peace of doux commerce is not predicated on justice. Sure, in the short run, you can do business with Pinochet’s Chile, privatize the national mining companies, and cut unemployment benefits, but not without incurring moral damage; people will see through it, in time, as they did in Seattle in 1999. Slobodian refers to the ratification of the WTO as a Pyrrhic victory; in their triumph, neoliberals painted a target on their backs.

Where does this leave us now? And what about Mercosur? I’m starting to feel the shape of an answer, but I’m not there yet. I think we’ll cover the gap between Seattle and the present day in a future dispatch. Until then, let’s take care of one other; as spoke the prophet Pratchett, there’s no justice, just us.

This post is the latest in my series of GNOME Foundation updates. I’m writing these in my capacity as Foundation President, where I’m busy managing a lot of what’s happening at the organisation at the moment. Each of these posts is a report on what happened over a particular period, and this post covers the current week as well as the previous one (23rd February to 6th March).

Audit time

I’ve mentioned the GNOME Foundation’s audit on numerous occassions previously. This is being conducted as a matter of routine, but it is our first full formal audit, so we have been learning a lot about what’s involved.

This week has been the audit fieldwork itself, which has been quite intense and a lot of work for everyone involved. The audit team consists of 5 people, most of whom are accountants of different grades. Our own finance team has been meeting with them three times a day since Tuesday, answering questions, doing walkthroughs of our systems, and providing additional documents as requested.

A big part of the audit is cross-referencing and checking documentation, and we have been busy responding to requests for information throughout the week. On last count, we have provided 140 documents to the auditors this week alone, on 20 different themes, including statements, receipts, contracts, invoices, sponsorship agreements, finance reports, and so on.

We’re expecting the draft audit report in about three weeks. Initial signs are good!

GUADEC 2026

Planning activity for GUADEC 2026 has continued over the past two weeks. That includes organising catering, audio visual facilities, a photographer, and sponsorship work.

Registration for the event is now open. The Call for Papers is also open and will close on 13 March – just one week away! If you would like to present this year, please submit an abstract!

If you would like travel sponsorship for GUADEC, there are two deadlines to submit a request: 15th March (for those who need to book travel early, such as if they need a visa) and 24th May (for those with less time pressure).

LAS 2026

This year’s Linux App Summit is happening in Berlin, on the 16th and 17th May, and is shaping up to be a great event. As usual we are co-organizing the event with KDE, and the call for proposals has just opened. If you’d like to present, you have until 23rd March to submit a paper.

The Travel Committee will be accepting travel applications for LAS attendees this year, so if you’d like to attend and need travel assistance, please submit a request no later than 13th April.

Infrastructure

On the infrastracture side, GNOME’s single sign on service has been integrated with blogs.gnome.org, which is great for security, as well as meaning that you won’t need to remember an extra password for our WordPress instance. Many thanks to miniOrange for providing us with support for their OAuth plugin for WordPress, which has allowed this to happen!

That’s it for my update this week. In addition to the highlights that I’ve mentioned, there are quite a number of other activities happening at the Foundation right now, particularly around new programs, some of which we’re not quite ready to talk about, but hope to provide updates on soon.

Painkillers are essential. (There are indicators that Neanderthals already used them.) However, many people don’t know about aspects of them, that could be relevant for them in practice. Since I learned some new things recently, here a condensed info dump about painkillers.

Many aspects here are oversimplified in the hope to raise some initial awareness. Please consult your doctor or pharmacist about your personal situation, if that’s possible. I will not talk about opioids. Their addiction potential should never be underestimated.

Here is the short summary:

• Find out which substance and dose works for you.
• With most painkillers, check if you need to take Pantoprazole to protect your stomach.
• Never overdose paracetamol, never take it with alcohol.
• If possible, take pain medication early and directly in the dose you need.
• Don’t take pain medication for more than 15 days a month against headaches. Some mediaction even fewer days.
• If you have any preexisting conditions, health risks, or take additional medication, check very carefully if any of these things could interacts with your pain medication.

Not all substances will work for you

The likelihood of some substances not working for some sort of pain for you is pretty high. If something doesn’t seem to work for you, consider trying a different substance. I have seen many doctors being very confident that a substance must work. The statistics often contradict them.

Common over the counter options are:

• • Ibuprofen
  • Paracetamol
  • Naproxen
  • Acetylsalicylic Acid (ASS)
  • Diclofenac

All of them also reduce fever. All of them, except Paracetamol, are anti-inflammatory. The anti-inflammatory effect is highest in Diclofenac and Naproxen, still significant in Ibuprofen.

It might very well be that none of them work for you. In that case, there might still be other options to prevent or treat your pain.

Gastrointestinal (GI) side effects

All nonsteroidal anti-inflammatory drugs (NSAIDs), that is, Ibuprofen, Naproxen, ASS, and, Diclofenac can be hard on your stomach. This can be somewhat mitigated by taking them after a meal and with a lot of water.

Among the risk factors you should be aware of are Age above 60, history of GI issues, intake of an SSRI, SNRI, or Steroids, consumption of alcohol, or smoking. The risk is lower with Ibuprofen, but higher for ASS, Naproxen, and, especially, Diclofenac.

It is common to mitigate the GI risks by taking a Proton Pump Inhibitor (PPI) like Pantoprazole 20 mg. Usually, if any of the risk factors apply to you. You can limit the intake to the days where you use painkillers. You only need one dose per day, 30–60 minutes before a meal. Then you can take the first painkiller for the day after the meal. Taking Pantoprazole for a few days a month is usually fine. If you need to take it continuously or very often, you have to very carefully weigh all the side effects of PPIs.

Paracetamol doesn’t have the same GI risks. If it is effective for you, it can be an option to use it instead. It is also an option to take a lower dose NSAIDs and a lower dose of paracetamol to minimize the risks of both.

Metamizole is also a potential alternative. It might, however, not be available in your country, due to a rare severe side effect. If available, it is still a potential option in cases where other side effects can also become very dangerous. It is usually prescription-only.

For headaches, you might want to look into Triptans. They are also usually prescription-only.

Liver related side effects

Paracetamol can negatively affect the liver. It is therefore very important to honor its maximum dosage of 4000 mg per day, or lower for people with risk factors. Taking paracetamol more than 10 days per month can be a risk for the liver. Monitoring liver values can help, but conclusive changes in your blood work might be delayed until initial damage has happened.

A risk factor is alcohol consumption. It increases if the intake overlaps. To be safe, avoid taking paracetamol for 24 hours after alcohol consumption.

NSAIDs have a much lower risk of affecting the liver negatively.

Cardiovascular risks

ASS is also prescribed as a blood thinner. All NSAIDs have this effect to some extent. However, for ASS, the blood thinning effect extends to more than a week after it has been discontinued. Surgeries should be avoided until that effect has subsided. It also increases the risk for hemorrhagic stroke. If you have migraine with aura, you might want to avoid ASS and Diclofenac.

NSAIDs also have the risk to increase thrombosis. If you are in as risk group for that, you should consider avoiding Diclofenac.

Paracetamol increases blood pressure which can be relevant if there are preexisting risks like already increased blood pressure.

If you take ASS as a blood thinner. Take Aspirin at least 60 minutes before Metamizole. Otherwise, the blood thinning effect of the ASS might be suppressed.

Effective application

NSAIDs have a therapeutic ceiling for pain relief. You might not see an increased benefit beyond a dose of 200 mg or 400 mg for Ibuprofen. However, this ceiling does not apply for their anti-inflammatory effect, which might increase until 600 mg or 800 mg. Also, a higher dose than 400 mg can often be more effective to treat period pain. Higher doses can reduce the non-pain symptoms of migraine. Diclofenac is commonly used beyond its pain relief ceiling for rheumatoid arthritis.

Take pain medication early and in a high enough dose. Several mechanisms can increase the benefit of pain medication. Knowing your effective dose and the early signs to take it is important. If you have early signs of a migraine attack, or you know that you are getting your period, it often makes sense to start the medication before the pain onset. Pain can have cascading effects in the body, and often there is a minimum amount of medication that you need to get a good effect, while a lower dose is almost ineffective.

As mentioned before, you can combine an NSAIDs and Paracetamol. The effects of NSAIDs and Paracetamol can enhance each other, potentially reducing your required dose. In an emergency, it can be safe to combine both of their maximum dosage for a short time. With Ibuprofen and Paracetamol, you can alternate between them every three hours to soften the respective lows in the 6-hour cycle of each of them.

Caffeine can support the pain relief. A cup of coffee or a double-espresso might be enough.

Medication overuse headache

Don’t use pain medication against headaches for more than 15 days a month. If you are using pain medication too often for headaches, you might develop a medication overuse headache (German: Medikamentenübergebrauchskopfschmerz). They can be reversed by taking a break from any pain medication. If you are using triptans (not further discussed here), the limit is 10 days instead of 15 days.

While less likely, a medication overuse headache can also appear when treating a different pain than headaches.

If you have more headache days than your painkillers allow treating, there are a lot of medications for migraine prophylaxis. Some, like Amitriptyline, can also be effective for a variety of other kinds headaches.

• Planning call in the morning, mail chew, prodded a proposal, lunch, sync with Laser, Anna & Andras, customer call.
• Pleased to see a really nice The Open Road to Freedom index, making it easier to see what is going on.
• Finally managed to get my Apple account to let me pay for a developer subscription - after lots of compound problems wasting hours. Clearly I've hit some buggy indeterminate state - still can't see subscriptions or country information: perhaps I'm stuck mid-atlantic beween two systems.

Six years ago I released Flatseal. Since then, it has become an essential tool in the Flatpak ecosystem helping users understand and manage application permissions. But there’s still a lot of work to do!

I’m thrilled to share that my employer Igalia has selected Flatseal for its Coding Experience 2026 mentoring program.

The Coding Experience is a grant program for people studying Information Technology or related fields. It doesn’t matter if you’re enrolled in a formal academic program or are self-taught. The goal is to provide you with real world professional experience by working closely with seasoned mentors.

As a participant, you’ll work with me to improve Flatseal, addressing long standing limitations and developing features needed for recent Flatpak releases. Possible areas of work include:

• Redesign and refactor Flatseal’s permissions backend
• Support denying unassigned permissions
• Support reading system-level overrides
• Support USB devices lists permissions
• Support conditional permissions
• Support most commonly used portals

This is a great opportunity to gain real-world experience, while contributing to open source and helping millions of users.

Applications are open from February 23rd to April 3rd. Learn more and apply here!