A flexible JSON/YAML linter for creating automated style guides
Top-level domain name registry service on Google Cloud Platform
A rules engine expressed in JSON
FLO: a simple markup language to write flowcharts with any text editor
Node-rules is a light weight forward chaining rule engine
CAM XML Editor for XML+JSON+Hibernate+SQL Open-XDX sponsored by Oracle
HEML is an open source markup language for building responsive email