November 2025: Finally a fatpak

Lots of development focused RetroDECK 0.10.0b news.

The RetroDECK Team have been hard at work stirring the development cauldron.

We also wish you a 🦃 Happy Thanksgiving 🦃 for those that celebrate it.

Highlights

News

Testing has started
What has science done: A fatpak?
RetroDECK 0.10.0b - What is in it and what is not?
Important: On Ponzu
What's new?
Testing will Start Soon
What’s coming next?

Note: We have switched from Patreon to OpenCollective

Read more here:

Donations & Licenses

What has science done: A fatpak?

RetroDECK 0.10.0b - Dastadly Dansband

Is a total rewrite of how RetroDECK is made under the pseudonym/codename: "Project Neo".

Let us explain what we have created and why it has taken us so long.

Simple flatpak

This is a simple flatpak

The application has all the things it needs in the Flatpak Runtime.

Advanced flatpak

This is a more advanced flatpak

The application needs to add additional libraries in addition to what is in the Flatpak Runtime. We internally call it the "library layer".

RetroDECK Classic

This is RetroDECK 0.9.4 and all older versions.

The application relied solely on the libraries provided by the Flatpak runtime.
This model forced a single runtime to serve all components, regardless of their divergent library requirements.
As individual components evolved, their library dependencies diverged significantly most notably the transition from Qt 5 to Qt 6 .
Because a Flatpak can host only one runtime, updating the runtime to satisfy a newer component (e.g., PCSX2) would inevitably break compatibility with others that depend on older libraries.
This incompatibility prevented us from upgrading several components to their latest releases in a easy maner and often required manual patches or custom builds.

RetroDECK "New"

This is RetroDECK 0.10.0b and future versions.

It was inspired by Docker and OSTree.

Base Runtime - Provides a stable, standard execution environment common to all parts, but it can be diverged if needed by components.
Libraries Layer - A curated collection of libraries and tools that are universally required across components.
Component Shared Libraries Layer - A curated collection of libraries that are component specific but can be shared with other components, thus saving space.
Component Specific Libraries Layer - Unique special libraries that are only bound to that component and can not be shared.
Component Applications - The binaries are within their own little environment.
RetroDECK - RetroDECK application at the top calling various components, layers and functions.

When traversing from the base runtime upward through a component’s flow from the Host OS to RetroDECK, the resulting view for that component reflects a concatenated set of libraries and dependencies specifically for that component (it only sees what it needs to see).

Effectively, each component are isolated within their own environment kinda like AppImage‑style sandboxed pre‑extracted, containers for every component that runs within a Flatpak total environment.

It's kinda like spinning up a docker container from a premade set of interchangeable layers for each component at the moment it runs.

Benefits

Isolation: Each component receives precisely the libraries it needs without affecting others from either or both shared-libraries and component specific libraries.
Flexibility: Newer components can be integrated by adding or adjusting only their custom layers, leaving the base runtime untouched.
Scalability: The architecture makes it much easier to add more components, keeping them updated and isolated.

RetroDECK  Alchemist: Independent Component Builds

Thanks to the RetroDECK Alchemist pipeline introduced in last month’s blog post, each component is now constructed independently from its official sources. RetroDECK merely pulls these finished artifacts into its own build process as sub‑modules via our own Component Recipe and Component Ingredient files (also in a past blog post).

The result is a fully modular architecture that remains packaged within a single Flatpak preserving the one button install and everything is included approach that people love and what RetroDECK is.

RetroDECK API

As outlined in an earlier blog post, a the new of RetroDECK API is superseding several legacy functions. The configurator has been refactored to align with this modular paradigm; it now assembles itself dynamically based on the components detected at runtime.

Looking ahead, we plan to leverage these modern APIs to develop a next‑generation RetroDECK Configurator built in Godot, further enhancing extensibility and user experience.

A fatpak

"This absolutely has to be the most complicated 
Flatpak implementation in existence."
//IceNine - RetroDECK Team

"Once I've been told that what I wanted to do with RetroDECK Classic
was impossible by various experts of everything flat and packaged. 
Look at it now! Look at it! Marvel in the insanity!" 
// Xargon - RetroDECK Team

"A fatpak!"
//Lazorne - RetroDECK Team

RetroDECK 0.10.0b - What is in it and what is not?

A this has been a huge endeavor we want to get an update out as soon as possible to update all the components, we have decided on a limited scope of new components to add in 0.10.0b.

What's not in it?

Important: On Ponzu

Ponzu does not work in version  0.10.0b (the temporary solution for installing legacy emulators). It simply cannot function with the new system.

You can keep your old version installed of RetroDECK installed and don't upgrade or block upgrades or downgrade from Flathub if needed.

What's new?

This is a short summery and not the full list.

Updated Everything

All components have been updated to their latest versions and are no longer in conflict.

Note: We'll decide which versions to lock in during the community testing phase for the bleeding-edge components.

Latest Runtime

RetroDECK is now using the latest KDE Runtime, no more angry and quite threatening terminal messages.

Changes

Way to many backend changes, we are so far over 1500+ commits since 0.9.4b.

Tweaks, Bug fixes, Cleanup and Polish

Tons of tweaks, bug fixes, cleanup and polish.

Fresh Folder Looks

New icons for RetroDECK's folders made by the RetroDECK Team's very own iconographer Lahrs. With a function to disable the iconset (for all you icon haters out there, we got you covered) and a structure to support more community made folder iconsets in the future.

Ryubing

Replaces legacy Ryujinx.

Azahar

Adds standalone support for 3DS emulation. Note: that Azahar does not support encrypted games.

OpenBOR

Is finally included, with its own RetroDECK wrapper: just create .bor or .openbor files and start fighting random dudes and dudettes.

GZDoom/UZDoom: 

RetroDECK wrapper:.doom File Improvements:

The RetroDECK .doom file format now supports:

.ini files (for the mods that need it).
Symbolic links.
Filenames that contain spaces.

While we originally planned to replace it with UZDoom, we may need to postpone that transition until the 0.11.0b release. The UZDoom team is currently taking official control of their Flatpak distribution and are preparing pre‑release AppImages. Previously, their Flatpak was built by a third party; now it’s being integrated into their own build pipeline.

RetroDECK team has told the the UZDoom team that they are happy to answer any Flatpak‑related questions or challenges they encounter.

Flips

A new tool, is built into RetroDECK via the Configurator. It can patch ROM hacks using .ips & .bps files.

Rewritten YML with finer‑grained permissions

The latest rewrite reduces the broad, global permissions that the RetroDECK Flatpak previously required.

Instead, we now request only the specific permissions and we’ve added inline comments explaining the rationale behind every permission. Looking ahead, we’re exploring additional incremental permission changes.

Our goal is to eventually enable features such as HDR support in RetroArch and light‑gun compatibility, though these things aren’t available yet.

Huzzah! Transparency!

Other

The Palette Swap bug for GB in RA on Quit should have been fixed (hopefully).
It got more content but it also takes a little less space, (maybe we should have said Thinpak).
There is a new folder under retrodeck/storage for misc data.

Testing will Start Soon

The Community Testing Phase of 0.10.0b will start soon.

There will be tons of bugs to iron out and things to configure better.

Keep in mind that: Cooker Builds are for testers only - see How‑to: Start Testing.

Do not file GitHub issues for Cooker builds.
These nightly releases contain unstable features and may destabilize or corrupt your RetroDECK setup.
The RetroDECK team is not liable for any data loss for not taking correct backups.
Communication of Cooker testing is primarily done on Discord in the Beta-Testing Channel.