I often use sequence diagrams when modelling systems. Right now I'm working on a problem that has a high degree of concurrency that I intend to solve using Go and it's CSP implementation.
What I need before I start coding is a modelling notation for CSP. If not CSP specifically then something that will enable me to express and explore the processes, channels and messages between them in order to compose/design the solution.
What are my options before inventing my own?