Derived, not chosen.
A connected set of methods that carry a business need all the way to running code — each structural decision derived from requirements, not left to taste.
Not another manifesto. Four well-known architectures have been derived from their public numbers under a published evidence protocol — predictions registered before the outcome was checked, each run carrying its own grade for how well it was insulated, one of them executed by operators quarantined from the answer. Misses are published next to hits. That is what makes “derived, not chosen” a claim you can check.
And you can run it. Three answer sheets over one domain, three different architectures, derived in your browser by a few hundred lines of ordinary code — no model involved. Change the answers and the architecture changes, for reasons it cites.
Run the derivation → See the replication kit, and send a counterexample →Stack-independent. Any language, any framework.
The same principles, made concrete in one stack.
Java is the reference realization, not a lock-in — every principle here ports to other languages.
Every book has a free course edition on this site. The books remain books.
The design method: a system's structure derived from what the business does, one operation at a time.
The next correct step: architecture derived, not chosen.
Hide the machinery, keep the meaning: deterministic code whose types state the business facts.