How To Validate Commands in a CQRS Application

Any of these sound familiar? Rubbish in rubbish out. Never trust user input. If you’ve ever built any sort of professional application you will have had to validate user input. Whether it is to ensure a valid email address or something more complicated. There are tried and tested ‘rules’ for doing this safely while being […]

Is a 100% Provable Audit Log Possible? – Hint, with Event Sourcing it Is and I’ll Show You How

If you’ve been developing for any length of time you’ve probably had to create an audit log. Here’s the question though, are any of these logs, a 100% provable audit of all changes in the system? I’m guessing not. With event sourcing, a 100% provable event log just happens to be a handy by product. So […]