Skip to main content

hummingbird desktop gap

Measured 2026-08-06. Every number below came out of a real rpm-md index, not out of a name, a release number or a base-image string. Reproduce with:

scripts/measure-hummingbird-gap.py \
  --report-json docs/hummingbird-desktop-gap.json \
  --build-order build-order-hummingbird-desktops.yml

The machine-readable result — including the per-desktop package lists, the BuildRequires cycles and the checksums of the indexes it was computed from — is docs/hummingbird-desktop-gap.json.

Why this was measured​

LUKS hummingbird:gnome fails on tuna-os/tunaOS (run 31100096864, job 92611346523). The image builds an artifact tagged gnome that contains no GNOME, and the desktop contract refuses to ship it: no gnome-shell, no wayland session file, no gdm, no nautilus, no gvfsd, no xdg-desktop-portal-gnome, no gnome-keyring-daemon, no pipewire/wireplumber user units, no compiled dconf database.

The chain in that log is:

  1. Chroot not found in the given Copr project (hummingbird-20251124-x86_64)
  2. TUNAOS_COPR_ENABLE_FAILED repo=jreilly1821/c10s-gnome-50-fresh
  3. dnf versionlock → No package found for gnome-shell, mutter, gdm, gnome-session-wayland-session, gnome-settings-daemon, gnome-control-center, gsettings-desktop-schemas, gtk4, libadwaita, pango, xdg-desktop-portal and xdg-desktop-portal-gnome.

Step 3 is the interesting one: the fallback to base repos found nothing. This document establishes why.

Index provenance​

indexrevisionprimary.xml sha256entries
public-hummingbird/x86_641786016019b92541eaf43fd4a8976710fa0035ae0c69b38aae7a0f241d61d87cd9bdd2a5123384 binary package names, 16506 (name, evr, arch) tuples
Fedora Rawhide Everything/x86_64/os1785994410dc3c7ec50508105e880c74f0178bf4723e770c73766654d833d1b2ad541e377466629 binary packages
Fedora Rawhide Everything/source/tree178599431387746b33eb94ca586ebc3d9407fc5c57ca6e8d9db8c899bc43aaa4fcd8ab531823178 SRPMs (used for BuildRequires ordering)

The declared and observed checksums matched on all three.

Finding 1 — Hummingbird is Fedora Rawhide, not EL10 and not Fedora 43​

build_scripts/lib.sh on tunaOS sets IS_FEDORA by testing whether the base image ref contains fedora. quay.io/hummingbird-community/bootc-os:latest does not, so hummingbird routes down the el10 section of manifests/desktops/gnome.yaml — the CentOS-Stream-10 GNOME-50 COPR path. That is a misclassification, and the index says so:

packagehummingbirdFedora 43Fedora Rawhide (45)
glib22.89.3-1.hum12.86.5-12.89.3-1.fc45
systemd261.2-1.hum1258.10-1261.2-1.fc45
gcc16.1.1-2.hum115.3.1-116.1.1-4.fc45.1
harfbuzz14.3.0-1.hum1—14.3.0-1.fc45
qt6-qtbase6.11.1-5.hum1—6.11.1-5.fc45
rust1.97.1-2.hum1—1.97.1-2.fc45
meson1.11.2-2.hum1—1.11.2-2.fc45
rpm6.0.1-6.hum1—6.0.92-2.fc45

Of 38 core packages present in both indexes, 30 are at the byte-identical upstream version and release as Rawhide and differ only in dist tag. Every one of Hummingbird's 16506 index entries carries .hum1.

So Hummingbird is a Fedora Rawhide rebuild. It is not EL10 and it is nowhere near Fedora 43.

Finding 2 — flipping IS_FEDORA would not have fixed it​

The task brief was right to be suspicious. Routing hummingbird to the fedora section of manifests/desktops/gnome.yaml sends dnf install gnome-shell … at Hummingbird's own repository, which contains:

gnome-shell   no      gtk4       no      cairo    no      pipewire   no
mutter        no      libadwaita no      wayland  no      wireplumber no
gdm           no      pango      no      mesa     no      dconf      no
nautilus      no      gvfs       no      libdrm   no      polkit     no
gsettings-desktop-schemas no      xdg-desktop-portal no   at-spi2-core no

Of the 58 packages tunaOS's GNOME manifest installs on a Fedora-family host, Hummingbird ships exactly one: avahi. Substring scans over all 3384 names return zero hits for cairo (only harfbuzz-cairo), wayland, mesa, libdrm, libxkbcommon, pixman, graphene, gdk, atk, at-spi, librsvg, json-glib, libsoup, accountsservice, NetworkManager, flatpak, gstreamer, upower, colord, iso-codes and xkeyboard-config.

The SBOM attached to the amd64 image (sha256:7fd344ca54b30cbc9566bd5ebaa133da2ebe5bea8d2ff656eecbfa6206243c3d.sbom, SPDX-2.3, blob sha256:bbe06272fa16dfc1…) agrees: 829 SPDX package entries, 444 distinct names, none of gnome-shell / mutter / gdm / nautilus / gtk / cairo / wayland / mesa / pipewire / pango.

Hummingbird publishes a base OS. It does not publish a desktop.

Finding 3 — Fedora Rawhide's binaries cannot simply be enabled instead​

The obvious shortcut — point dnf at Fedora Rawhide, since Hummingbird tracks it — does not work. The eight packages that do diverge are the load-bearing ones:

packagehummingbirdRawhideconsequence
glibc2.43-8.hum12.44-1.fc45637 Rawhide binaries require GLIBC_2.44, which Hummingbird does not provide
libxml22.15.3 (libxml2.so.16)2.13.9 (libxml2.so.2)soname mismatch in both directions
openssl3.5.6 (libcrypto.so.3)4.0.1 (libcrypto.so.4)soname mismatch
python33.14.63.15.0~b4different libpython3.x.so.1.0
fontconfig2.17.12.18.2(the same class of break that bit skipjack; see AGENTS.md)

Within the GNOME closure alone, 20 packages require libxml2.so.2, 5 require GLIBC_2.44 and 5 require libcrypto.so.4 / libssl.so.4. Those are hard install failures, not warnings. The packages have to be rebuilt against Hummingbird's buildroot, which is exactly what this repository is for.

Finding 4 — the size of the gap​

Roots are each desktop's install_packages plus required_packages from manifests/hummingbird-desktops.yaml. Closure is transitive Requires: against Rawhide, stopping wherever Hummingbird can already satisfy the capability from any package, Provides: or shipped file.

desktoprootsalready in targetbinaries to buildsource packages to buildtiers
gnome581 (avahi)40529810
kde13045938419
cosmic22020116310
niri26036931010
xfce15031624812
union670

Two roots are absent from Fedora entirely and cannot be sourced from dist-git: dms-greeter (niri, DankMaterialShell) and xfwl4 (xfce, the Wayland xfwm fork). Those stay upstream_rpm: / local: sources in the catalog.

This is not "a subset of GNOME is missing". It is the whole desktop stack — mesa, webkitgtk, samba, gstreamer1, pipewire, pulseaudio, cairo, gtk3, gtk4, NetworkManager — plus GNOME on top.

Finding 5 — build order, and the bootstrap cycle​

Tiers are a topological order over the BuildRequires graph taken from Fedora's source repository index (that is what rpm records on an src package), condensed by strongly connected components first. Ordering by runtime Requires: instead produces a single 142-package tier and is wrong; --source-reference '' falls back to it and the report labels which was used (tier_ordering).

Every desktop has a genuine BuildRequires cycle that no ordering can break. For GNOME it has 60 members:

ModemManager NetworkManager at-spi2-core bluez cairo colord flite gcr
gdk-pixbuf2 geoclue2 geocode-glib glib-networking glycin gnome-desktop3
gnome-settings-daemon gobject-introspection graphene gsettings-desktop-schemas
gssdp gstreamer1 gstreamer1-plugins-bad-free gstreamer1-plugins-base gtk3 gtk4
gupnp gupnp-igd gweather-locations json-glib libadwaita libcanberra
libcloudproviders libdecor libepoxy libgudev libgusb libgweather libical
libinput libmbim libnice libnotify libpcap libproxy libqmi libqrtr-glib
librsvg2 libsecret libsndfile libsoup3 libwacom mpg123 mutter pango pipewire
polkit ppp pulseaudio pygobject3 sbc upower xorg-x11-server-Xwayland

plus {libglvnd, libva, mesa} and {libxkbcommon, xkeyboard-config}. These are marked bootstrap: true in the generated build order. They need the treatment this repository already uses for EL10 — src/gnome-50/glib2/glib2-bootstrap.spec and gobject-introspection-bootstrap.spec — or a first --nocheck/reduced-feature pass, then a second full pass. The mock config keeps Fedora Rawhide as a priority-99 buildroot fallback precisely so the first pass has headers to build against; Rawhide is never a repository on a produced image.

What was NOT verified​

Honesty about the boundary of the measurement:

  • No RPM was built. 670 source packages is a build-farm job, not a session's work. Nothing has been published to r2:bluefin/hummingbird/20251124-x86_64/ yet, and that path currently serves no repodata.
  • The closure follows Requires: only. Recommends: are excluded, so the real installed set is somewhat larger; weak deps do not change which packages must exist.
  • Rich/boolean dependencies ((a or b)) are skipped rather than solved. Four appeared in the GNOME closure, all of them if-guarded optional loaders.
  • Provider choice for a capability with several providers is "exact name match, else shortest name" (choose_provider). A different choice would move a few source packages in or out of the list.
  • x86_64 only. aarch64 is a separate index and has not been measured.