Emulation of those specific z/VM features for OpenSolaris is included starting with Hercules Version 3.07. Sine Nomine Associates brought OpenSolaris to System z, relying on features provided by z/VM. Mainframe Linux distributions include SUSE Linux Enterprise Server, Red Hat Enterprise Linux, Debian, CentOS, and Slackware. Several distributors provide 64-bit z/Architecture versions of Linux, and some also provide ESA/390-compatible versions. They run well on Hercules, and many Linux on IBM Z developers do their work using Hercules.
Its developers ruled out using machine-specific assembly code to avoid problems with portability even though such code could significantly improve performance. The emulator is written almost entirely in C.