2024 Display Next Hackfest

14-16 May | A Coruña, Galicia, Spain

The hackfest

The 2024 Display Next Hackfest will take place in A Coruña, Galicia, Spain from May 14th (Tue) to May 16th (Thu).


The Display Next Hackfest is an event where talented developers will gather to explore the latest technologies and trends in the Linux Display Stack. It has an unconference format where participants propose topics for presenting, roadmapping, discussing and examining together. It aims to unblock bottlenecks, design solutions, raise pitfalls and accommodate the needs of each layer of the display stack. Participants should feel free to propose any topic which interests them. Some topics from the previous edition include: HDR and color management, frame timing and variable refresh rate (VRR), atomic flips, testing and CI, etc.

Plans and Goals

  1. Keep moving! Continue your work on upstream design, implementation and documentation until the hackfest.
  2. “Are you okay with that?” Present the current status of your work, explain decisions, concerns and results. Let’s compromise.
  3. Share your pains. What is well aligned with the generic approach? What is not (singularities) and how can we find room for it? Whatever your doubts, we resolve them together!
  4. “Something went wrong.” Share failing tests or inconsistent results. Let’s take a look together and find how to overcome them!

The hackfest will last three days following a “Unconference” format. Check the event timetable and agenda below.

* Information about the previous year can be found on Shell Display Next 2023 wiki.

Timetable (Central European Summer Time - CEST)

Time (CEST) / Date Tue, May 14 Wed, May 15 Thu, May 16
09:00 - 9:30 Walk to Igalia HQ Walk to Igalia HQ Walk to Igalia HQ
09:30 - 10:10 Welcome! (Igalia HQ & participants intro) Recap & Planning Recap & Planning
10:10 - 11:40 Introduction (Participants & Topics) Session: Real time scheduling & async KMS API Session: Display Control & Session: Display Mux
11:40 - 12:00 20-min break* 20-min break* 20-min break*
12:00 - 13:30 Session: VRR & Frame timing Session: Power Savings vs Color/Latency Session: VRR & Frame timing & Session: Content-Adaptive Scaling & Sharpening
13:30 - 14:30 Lunch* Lunch* Lunch*
14:30 - 16:00 Session: HDR & Color Management (kernel) Session: HDR & Color Management (userspace) Wrapping-up (length: 1h)
16:00 - 16:20 20-min break* 20-min break*
16:20 - 18:30 Session: HDR & Color Management (Use-cases/Testing) Session: Strategy for video and gaming use-cases Social Activity
20:30 Hackfest Dinner (sponsored by Igalia)

* Lunches and coffee-breaks offered to participants in the office by Igalia.

Find more details about general schedule and sessions here.



  • Proposal with new DRM object type:
    • Presentation of GPU-vendors features;
    • Status-update of plane color management pipeline per vendor on Linux;
  • HDR/Color Use-cases:
    • Google/ChromeOS GFX view about HDR/per-plane color management and VKMS;
    • HDR gainmap images and how we should think of HDR;
    • Pain points and wish lists of HDR images and video on ChromeOS.
  • Post-blending Color Pipeline.
Color/HDR testing/CI
  • VKMS status-update;
  • Chamelium boards, video capture.
  • Linux color handling and management;
  • color-management protocol status-update;
  • color-representation and video playback.

Display control

  • HDR signalling status-update;
  • backlight status-update;
  • EDID and DDC/CI.

Strategies for video and gaming use-cases

  • Multi-plane support in compositors:
    • Underlay, overlay, or mixed strategy for video and gaming use-cases;
    • KMS Plane UAPI to simplify the plane arrangement problem;
    • Shared plane arrangement algorithm desired.
  • HDR video and hardware overlays.

Frame timing and VRR

  • Frame timing:
    • Limitations of uAPI;
    • Current user space solutions;
    • Brainstorm better uAPI;
  • Cursor/overlay plane updates with VRR;
  • KMS commit and buffer-readiness deadlines;

Power Saving vs Color/Latency

  • ABM (adaptive backlight management);
  • PSR1 latencies;
  • Power optimization vs color accuracy/latency requirements.

Content-Adaptive Scaling & Sharpening

  • Content Adaptive Scalers on display hardware;
  • New drm_colorop for content adaptive scaling;
  • Proprietary algorithms.

Display Mux

  • Laptop muxes for switching of the embedded panel between the integrated GPU and the discrete GPU;
  • Seamless/atomic hand-off between drivers on Linux desktops.

Real time scheduling & async KMS API

  • Potential benefits: lower latency input feedback, better VRR handling, buffer synchronization, etc.
  • Issues around “async” uAPI usage and async-call handling.

More details here.


See the list of participants here.


Igalia Headquarters
Bugallal Marchesi 22, 1º
15008, A Coruña
Galicia (Spain)

OpenStreetMap Page

Travel And Accommodation

Fly to A Coruña (recommended)

A Coruña Airport (LCG) is connected to Geneva, London/Gatwick, Milan, Barcelona and Madrid.

To get to the venue from A Coruña Airport:

  • Taxi - 15 min - Airport taxi stand.

    Fare: The cost is usually 15-20€.
    Payment method: Cash or credit card (ask beforehand).

  • Bus - 20 min - Airport bus stop.

    Use the Airport-City Center Bus line (Line 4051 Centro da cidade - Aeroporto.).
    Stop at "Estación de Autobuses".
    On the way back you should pick the bus on the other side of the road, in the gas station ("gasolinera").
    Fare: 1.55€ (0.88€ with metropolitan card).
    Payment method: Only cash, buy on the bus.
    From bus station to Igalia office (8 min walk).

    • On working days, both from A Coruña and from the airport, buses run from 7:15 to 21.45 every half hour. Early bus at 05:00 (from city center) and 06:15. Night bus at 23:15, 23:30 and 00:30.
    • On Saturdays, Sundays and bank-holidays they leave from A Coruña every hour from 6:30 to 23:30, and from the airport from 6:00 to 23:00 also every hour. Early bus to the airport at 05:00.

Fly to Santiago

Santiago Airport (SCQ) is connected to Madrid, Barcelona, Amsterdam/Schiphol, Basel/Mulhouse, Barcelona, Brussels, Dublin, Edinburg, Frankfurt, Memmingen, Geneva, London, Milan/Bergamo, Bologna, Paris, Bordeaux, Marsella and Zurich.

About 50km from to Coruña, it's a good option if you have a direct flight, but requires to go to A Coruña from there.

To get to the venue from Santiago Airport:

  • Bus/Taxi + Train - 40 min (bus)/20 min (taxi) + 30 min (train)

    Bus from Santiago Airport to train station - Airport bus stop
    Stop at Train Station ("Hórreo (estación)" "Estación de Tren/Ferrocarril").
    Fare: 1€.
    Payment method: Cash.

    Taxi from Santiago Airport to train station - Airport taxi stand.
    Fare: Fixed fare 21€.
    Payment method: Cash or credit card (ask beforehand).

    Train from Santiago to A Coruña
    Fare: Depends on the schedule.
    Payment method: Cash or credit card buying tickets at the train station. Or buy them in advance at refe.com or thetrainline.com (Warning: On Sunday's afternoons/evengins or Monday's mornings the train can be full so booking in advance is recommended).
    From A Coruña train station to Igalia office (11 min walk).

  • Taxi - 45 min

    Direct taxi from Santiago Airport to A Coruña - Airport taxi stand.
    Fare: Around 80€.
    Payment method: Cash, credit card (ask beforehand), or book in advance at taxigalicia.com.

  • Direct bus - 60 min

    Bus from Santiago Airport to A Coruña - Bus from Santiago Airport to A Coruña Bus Station ("Estación de Autobuses").
    Fare: 6.70€.
    Payment method: Cash or online (in Spanish).
    Schedules (quite limited).
    From Bus Station to Igalia office (8 min walk).

Fly to Porto (Portugal)

Porto Airport (OPO) is connected to several big cities like: New York, Toronto, Montreal, Rio, Sao Paulo, Londo, Frankfurt, Helsinki, Paris.

To get to the venue from Porto Airport:

  • Rent a car - 3 hours
    Porto airport is about 300km away from A Coruña.
  • Bus - 5 hours
    Fare: 50€.
    Payment method: Buy ticket online.
    From bus station to Igalia office (8 min walk).


Bus connections to A Coruña are available from all major cities in Spain.

  • Bus: Bus tickets to get to A Coruña are available from ALSA amongst other carriers.
    From Bus Station to Igalia office (8 min walk).


Train connections to A Coruña are available from all major cities in Spain.

  • Train: Train tickets to get to A Coruña are available from Renfe or thetrainline.com.
    From train station to Igalia office (11 min walk).


It is also possible to drive to A Coruña.


There are a bunch of nice hotels around the event venue (Palexco).


  • We recommend staying in Hotel Avenida (Budget), which is a five minute walk from Igalia’s office and is offering a discounted rate for hackfest attendees. Please, contact us for booking with special rates - let us know the room size (single or double) and name(s) under which we should book the room.
  • Hotel Attica21 Coruña (First class. 15 min walking)
  • AC by Marriot (First class. 15 min walking)

Covid rules

The 2024 Display Next Hackfest organizers continuously monitor local guidelines and regulations related to COVID-19. The changeable nature of the pandemic means that regular updates to this policy may be necessary. We will inform registered participants about any substantial changes to this document.

By attending, you agree to abide by applicable Spanish regulations for indoor activities and the 2024 Display Next Hackfest health & safety rules, and to conduct yourself in accordance with all provided instructions. This will include, but is not limited to:

  • refraining from coming to the event if you have COVID-19 or its symptoms, or if you are required to be in self-isolation or quarantine by COVID-19 regulations in Spain or at the location you are travelling from;
  • complying with the prevailing mask-wearing policy communicated at the event; Even if when regulations have removed the obligation to wear masks, the organization establishes masks as recommended indoors;
  • following instructions on physical distancing and crowd circulation at the event;
  • observing good hand-washing and hygiene etiquette.

More information can be found at: sanidad.gob.es.


  • Usual timetables. Lunch time: 13:00 - 15:30. Dinner time: 20:30 - 22:30. Note that you won't be able to find a restaurant open for lunch at 12:00 or for dinner at 18:00, neither at 19:00; thus you might want to start your day a bit "later" than usual. Main reason behind this is that A Coruña is in the same timezone than central Europe, and sunrise and sunset times are somehow shifted with regard to common standards in other parts of the world.
  • Language. The official languages in A Coruña are Galician and Spanish. Not everybody is able to understand or speak English (in the bus, taxi, hotel, etc). The 2024 Display Next Hackfest is run in English.
  • Climate. A Coruña has a climate heavily moderated by the Atlantic Ocean. Average temperatures are around 10ºC (51ºF) in winter and 19ºC (66ºF) during summer. (See more info at Wikipedia).
  • Tourism. Tourism A Coruña website.


Host & Organizer

Igalia logo

Code Of Conduct

Igalia is a project which attempts to make space for equality within a system that is highly unequal. In order to do this, we must counter the structural discrimination that surrounds us in the world and, in particular, in our industry. Our desire is expressed through our foundational principles, our internal processes, and guidelines for how we treat each other. The ultimate goal of the code of conduct is to keep Igalia welcoming for all those who interact with us in good faith and to be a positive and fulfilling influence in the lives of the people within our community.

This code of conduct has three sections. In the first section, we present the ideals we believe should underlie interactions within Igalia. In the second section, we describe types of unacceptable behavior. Finally, in the third section, we describe how to report problems, so that we can take steps to ensure that Igalia remains both safe and healthy.

This policy applies in all of the following contexts:

  • The Igalia offices
  • All internal and external meetings including assemblies and the partners council
  • All mailing lists, bug trackers, wikis, and all other online services
  • Igalia sponsored social gatherings such as summits
  • Igalia hosted conferences, hackathons, and other public and private events
  • At all times where a person is acting as a representative of Igalia, including sponsored external events, communities, or using a company e-mail address

Expected Behavior

Be Respectful and Kind

Always assume that others are competent and trying to do their best. Look out for one another and offer help when it is appropriate and welcome. The words you choose are important, so choose them carefully. Be aware that words and imagery have different meanings across countries, cultures, and communities. If you are unsure whether something is appropriate, it is better to keep it to yourself. Be quick to apologize and learn from your mistakes.

Include Everyone

Encourage all voices. Amplify new points of view and listen actively. If you find yourself dominating a discussion, it is especially important to step back and make room for other voices. When repeating ideas and suggestions, give credit to the person who introduced them. Be aware of the amount of time taken up by the dominant members of the group. When it is possible, make sure there are alternative ways to contribute.

Seek Understanding and Consensus

Discussion and debate are essential to Igalia, but we have to remember that we are not trying to “win” disagreements. Always try to encourage constructive discussions and inclusive thinking so that we are working with a wide range of perspectives. At the same time, reject intolerance and the dehumanization of others.

Speak Up

The responsibility for maintaining a safe environment is shared among all of us. If you think something violates the code of conduct, say something.

Unacceptable Behavior

  • Unwelcome, offensive or hurtful comments or jokes related to age, gender, gender identity and expression, sexual orientation, disability, illnesses, mental illness, neuro(a)typicality, physical appearance, body size, race, religion, national origin, nationality, ancestry, or pregnancy
  • Unwelcome, offensive, or hurtful comments or jokes regarding a person’s lifestyle choices and practices
  • Deliberate misgendering, use of “dead” or rejected names, or use of inappropriate nicknames
  • Gratuitous or off-topic sexual images or behavior, non-consensual physical contact and simulated physical contact, or any other type of unwelcome sexual attention
  • Violence, threats of violence, or incitement of violence, including encouraging others to commit self-harm
  • Deliberate intimidation or the sabotage of work
  • Stalking or unwelcome photography, recording, or logging of online activity
  • Sustained disruption of discussion
  • A pattern of inappropriate social contact, such as requesting/assuming inappropriate levels of intimacy with others
  • Deliberate “outing” of any aspect of a person’s identity without their consent except as necessary to protect vulnerable people from intentional abuse
  • Publication of private and personal (unrelated to work) communication, except when it is used as evidence of a code of conduct violation
  • Retaliation for reporting a code of conduct violation

It is impossible to list all types of unacceptable behavior, but a general rule is that conduct committed in bad faith, which causes harm or distress, or after requests to stop is unacceptable. This includes actions taken without malice. When in doubt, take responsibility for your actions, apologize, and move on. Finally, reporting a violation of the code of conduct does not ever violate the code of conduct.


There are several ways that you can report behavior that makes you or others feel unsafe, unwelcome, or excluded. These include:

  • Emailing (conduct@igalia.com)
  • Speaking to the organizer of an Igalia hosted event: Melissa Wen.

Emails sent to conduct@igalia.com are received by:

  • Andy Wingo
  • Brenna Brown
  • Germán Poo-Caamaño
  • Ioanna Dimitriou
  • Javier Moran
  • Jeongeun Kim

For urgent issues, you may also call +34 951 204 844 and then enter the PIN 1818 followed by the hash sign (#).

People reported as violating the code of conduct will not take part in the process of handling that report. After the report, immediate action will be taken to ensure the safety and well-being of those involved.

Potential consequences of unacceptable behaviour:

  • Removal from an event
  • Temporary removal from Igalia services or locations
  • Permanent removal from Igalia services or locations
  • Termination of employment