From haladir.com, we do legacy mainframe modernization using formal methods, property-based testing, and other stuff. We open-sourced MOBOL, a Python SDK for automating interaction with mainframe environments running on UniKix COBOL systems. It enables programmatic testing and automation of CICS transactions on AWS EC2-hosted instances. Running COBOL is extremely difficult, so we made this to make it a bit easier. If anyone works in COBOL, or legacy systems, reach out, we'd love to talk.