Red Hat Enterprise Linux 9.0 is now officially available to Red Hat customers as stable, building off the RHEL9 beta available since the end of last year. Red Hat Enterprise Linux 9 ships with a wealth of updated software components and derived from CentOS Stream. On the versioning front, RHEL9 has GCC 11 as the default system compiler, Python 3.9, RPM 4.16, PHP 8.0, updated LLVM / Rust / Go compilers, a plethora of optimizations, OpenSSL 3, Ruby 3.0, and much more to enjoy with this major release for enterprise Linux users. Linux 5.14 is the kernel in use by RHEL 9.0 albeit with various kernel back-ports.
There will be several community alternatives based on RHEL 9.0 soon enough, too, so if you want to run something RHEL like without all the corporate support, there’s enough options, too.