CentOS vs Fedora — bluefin-lts Build Context#

bluefin-lts is built on CentOS Stream 10, not Fedora. This has critical implications for agents and contributors.

What does NOT exist on CentOS Stream 10#

What to use instead#

• Third-party packages: Use EPEL (dnf install epel-release) — the CentOS equivalent for extra packages
• COPR repos: You can still USE COPR repos via direct .repo URL — but you must use the epel-10 chroot name, not centos-stream-10 (see below)
• Akmods: Pull from ghcr.io/ublue-os/akmods-*:centos-10 (not coreos-stable)
• Package availability: Always verify a package exists in CentOS Stream repos before adding it

COPR chroot naming — critical#

epel-10 and centos-stream-10 are the same thing from the OS perspective, but COPR projects choose which chroot name they build against. Most COPR projects targeting EL10 use epel-10, not centos-stream-10.

Always check the COPR API before hardcoding a chroot name:

curl -s "https://copr.fedorainfracloud.org/api_3/project/search?query=OWNER/PROJECT" | python3 -m json.tool | grep chroot_repos -A 10

Correct URL pattern:

# ✅ Use epel-${MAJOR_VERSION_NUMBER} for most COPR projects
dnf config-manager --add-repo "https://copr.fedorainfracloud.org/coprs/OWNER/PROJECT/repo/epel-${MAJOR_VERSION_NUMBER}/OWNER-PROJECT-epel-${MAJOR_VERSION_NUMBER}.repo"

# ⚠️ Some COPR projects DO use centos-stream-10 — verify first
dnf config-manager --add-repo "https://copr.fedorainfracloud.org/coprs/OWNER/PROJECT/repo/centos-stream-${MAJOR_VERSION_NUMBER}/OWNER-PROJECT-centos-stream-${MAJOR_VERSION_NUMBER}.repo"

Real example (issue #48, fixed 2026-06-04): jreilly1821/c10s-gnome-50 only has epel-10 chroots. Using centos-stream-10 caused a 404 on every GDX build until the URL was corrected.

Common mistakes to avoid#

1. DO NOT copy copr_install_isolated() patterns from bluefin build scripts — dnf copr enable is blocked by CI guard
2. DO NOT use dnf5 copr enable — the subcommand is unavailable and blocked
3. DO NOT assume centos-stream-10 is the right COPR chroot — verify with the API; most projects use epel-10
4. DO NOT use coreos-stable or Fedora-version akmods tags
5. DO NOT assume Fedora package names match CentOS package names exactly

CI guard#

A CI step in pr-testsuite.yml checks that copr enable does not appear in build_scripts/. If you see this CI failure, replace with a direct dnf config-manager --add-repo URL using the correct chroot name. LTS does not use bluefin's build_files/ path.