app.fluxer.json -- Flatpak manifest defining the build, runtime, permissions, and sources.
app.fluxer.metainfo.xml -- AppStream metadata for the app store listing (description, categories, content rating, etc.).
app.fluxer.desktop -- XDG desktop entry so the app appears in desktop launchers.
icon-256.png -- Application icon (256x256). This file must be extracted from the build resources or provided separately; it is not checked in.

Placeholder SHA256 hashes

The sha256 values in app.fluxer.json are set to PLACEHOLDER_SHA256_X64 and PLACEHOLDER_SHA256_ARM64. These are updated automatically by flatpak-external-data-checker via the x-checker-data configuration on each source. When preparing a manual build, replace them with the actual SHA256 checksums of the downloaded tar.gz archives.

Icon

The icon-256.png file needs to be provided before building. You can extract it from the Electron build resources:

cp ../../build_resources/icons/256x256.png icon-256.png

Or generate it from the source SVG/PNG in the build resources directory.

Testing locally

Install the required runtime and base app if you haven't already:

flatpak install flathub org.freedesktop.Platform//24.08 org.freedesktop.Sdk//24.08 org.electronjs.Electron2.BaseApp//24.08

Then build and install:

flatpak-builder --user --install build-dir app.fluxer.json

Run the app:

flatpak run app.fluxer

Flathub submission

To submit to Flathub, fork the flathub/flathub repository and open a pull request adding app.fluxer.json along with the supporting files. Refer to the Flathub submission guide for current requirements.