Bounded Contexts

Deal with large models by dividing them into different Bounded Contexts and being explicit about their interrelationships. In dealing with any Personally Identifiable Information, have a Subject Matter Expert on Australian Privacy Laws and Data Retention Laws. Don't try to be a gatekeeper, instead, ensure that everyone has the skills, knowledge and... tools necessary to release changes in a safe way. Verify with runtime monitoring tools, WAFs and other realtime tooling. In a distributed computing environment, failures are inevitable. It's more pragmatic to plan for failure and test for it. For example, if a user's name changes, it should only need to change in one place to replicate throughout all systems. The most expensive security failure is the one that's already happened. Building in the cloud still costs money to the business, that should be planned and budgeted for. There's no recovering raw events from aggregates, but aggregates can always be calculated later For example, personally, I favour Contract Testing over Integration Testing. With a complex system, production cannot be accurately reproduced. When relying on Integration testing, every discrepancy from production to the testing environment is an untested venue for failure. Contract Testing provides better coverage, see https://www.destroyallsoftware.com/talks/boundaries and http://blog.thecodewhisperer.com/permalink/integrated-tests-are-a-scam If you're awoken at 3 AM, all the information you need to diagnose an issue should already have been collected. Collect a record of all steps that needed to be taken to stabilise and resolve the issue, and fix any gaps in data collection. SSH is often a crutch for poor observability of a system. Avoid these three wherever possible. Unless you're a database vendor, it's not your core competency. Lean on services who can provide better support than the business could ever justify. A backup isn't working until you can prove that it works. Think of the consequences of a backup failing, and plan for this as well. ...Read More