The CodeReady Builder (CRB) repository ships development headers, static libraries, and build dependencies that don’t belong in the base OS repos but are essential for compiling software from source, building RPMs, or satisfying EPEL package dependencies. If you’ve ever hit a missing -devel package during a build, CRB is almost certainly where it lives.
On RHEL, this repository is officially called CodeReady Linux Builder. Rocky Linux and AlmaLinux ship the same content under the shorter name CRB. The packages are identical – only the repo name and enablement method differ.
What’s in the CRB Repository?
CRB contains packages that application developers and packagers need but that most end-user systems don’t install by default. Common examples include:
- Development headers (
*-develpackages) for system libraries - Static libraries for linking
- Documentation and man page generators (
doxygen,asciidoc) - Build tools and compilers not in the base repos
- Performance profiling tools
- Libraries required as build dependencies by EPEL packages
Many EPEL packages depend on CRB. If you enable EPEL without CRB, you’ll run into broken dependency chains. Always enable CRB first when you plan to use EPEL.
Enable CRB on RHEL 10
RHEL 10 uses subscription-manager to manage repository access. Your system must have an active Red Hat subscription attached before you can enable the repository.
Verify your subscription status first:
sudo subscription-manager statusYou should see Overall Status: Current in the output. If the subscription is not attached, register and attach it:
sudo subscription-manager register --username your-rh-username --password your-rh-password
sudo subscription-manager attach --autoWith a valid subscription in place, enable the CodeReady Builder repository for RHEL 10:
sudo subscription-manager repos --enable codeready-builder-for-rhel-10-x86_64-rpmsThe repository should now appear in your enabled repo list. Confirm it with:
sudo subscription-manager repos --list-enabled | grep -i codereadyYou should see the codeready-builder-for-rhel-10-x86_64-rpms repository listed as enabled.
RHEL 10 on aarch64 (ARM)
If you’re running RHEL 10 on ARM-based hardware, the repo name includes the architecture:
sudo subscription-manager repos --enable codeready-builder-for-rhel-10-aarch64-rpmsEnable CRB on Rocky Linux 10
Rocky Linux ships CRB as a standard repository that’s disabled by default. No subscription is needed – just enable it with dnf:
sudo dnf config-manager --enable crbVerify the repository is now active:
dnf repolist | grep -i crbThe output should confirm the CRB repository is enabled with its package count:
crb Rocky Linux 10 - CRBEnable CRB on AlmaLinux 10
AlmaLinux 10 follows the same approach as Rocky Linux. The CRB repo is present but disabled by default:
sudo dnf config-manager --enable crbConfirm the repo is enabled:
dnf repolist | grep -i crbYou should see the CRB repository listed with available packages:
crb AlmaLinux 10 - CRBEnable CRB on RHEL 9 / Rocky Linux 9 / AlmaLinux 9
If you’re still running version 9 of any RHEL-family distribution, the process is nearly identical. Here are the commands for each:
RHEL 9:
sudo subscription-manager repos --enable codeready-builder-for-rhel-9-x86_64-rpmsRocky Linux 9 / AlmaLinux 9:
sudo dnf config-manager --enable crbThe crb repo ID is the same on both Rocky 9 and AlmaLinux 9. The command works identically on version 9 and 10 for these distributions.
Verify CRB is Working
Regardless of which distribution you’re on, verify the repo is active and packages are available by listing all enabled repositories:
dnf repolistOn RHEL 10, you’ll see codeready-builder-for-rhel-10-x86_64-rpms in the list. On Rocky and AlmaLinux, it shows as crb.
You can also search for a known CRB package to confirm the repo is providing content:
dnf search --repo crb doxygenOn RHEL 10, use the full repository ID instead:
dnf search --repo codeready-builder-for-rhel-10-x86_64-rpms doxygenInstall a Package from CRB
To confirm everything works end to end, install a package that only exists in the CRB repository. The doxygen documentation generator is a good test candidate since it’s a common build dependency:
sudo dnf install -y doxygenVerify the installed package and check which repository it came from:
dnf info doxygenThe Repository field in the output should show crb (Rocky/Alma) or codeready-builder-for-rhel-10-x86_64-rpms (RHEL), confirming the package was pulled from the correct repository.
CRB and EPEL – Why Both Matter
EPEL (Extra Packages for Enterprise Linux) is the most popular third-party repository for RHEL-family systems. Many EPEL packages depend on development libraries that live exclusively in CRB. Without CRB enabled, EPEL installs will fail with unresolved dependency errors.
The recommended order is to enable CRB first, then install EPEL:
sudo dnf config-manager --enable crb
sudo dnf install -y epel-releaseOn RHEL 10, enable CRB via subscription-manager, then install the EPEL release package:
sudo subscription-manager repos --enable codeready-builder-for-rhel-10-x86_64-rpms
sudo dnf install -y https://dl.fedoraproject.org/pub/epel/epel-release-latest-10.noarch.rpmAfter enabling both, verify they’re active:
dnf repolistYou should see both the CRB and EPEL repositories in the enabled list. With both active, you’ll have access to thousands of additional packages for development, monitoring, and system administration.
Disable the CRB Repository
If you ever need to disable CRB, reverse the process with the matching command for your distribution.
Rocky Linux / AlmaLinux:
sudo dnf config-manager --disable crbRHEL 10:
sudo subscription-manager repos --disable codeready-builder-for-rhel-10-x86_64-rpmsKeep in mind that disabling CRB while EPEL packages are installed may cause dependency issues on the next system update. Only disable it if you’re sure no installed packages depend on it.
Quick Reference
| Distribution | Command to Enable CRB |
|---|---|
| RHEL 10 | sudo subscription-manager repos --enable codeready-builder-for-rhel-10-x86_64-rpms |
| RHEL 9 | sudo subscription-manager repos --enable codeready-builder-for-rhel-9-x86_64-rpms |
| Rocky Linux 10 | sudo dnf config-manager --enable crb |
| Rocky Linux 9 | sudo dnf config-manager --enable crb |
| AlmaLinux 10 | sudo dnf config-manager --enable crb |
| AlmaLinux 9 | sudo dnf config-manager --enable crb |
I did that. And it’s enabled. Now how am i supposed to use it to start creating apps?