Use Rastrillo v0.28 (module `amadan.net/rastrillo/rastrillo`, available
through the Go module proxy). Read `~/amadan.net/rastrillo/rastrillo/SKILL.md`
first, and build the app the way Rastrillo recommends: its platform
contract (`Resolve`/`Serve`/`Run`), routing, sessions, migrations and so
on. Two exceptions, both from the bakeoff's shared rules: the UI is
TodoMVC's markup and CSS (not Rastrillo's design system), and the
contract's Origin check is the cross-site protection, because the shared
tests and load tests post without a CSRF token. If Rastrillo's CSRF
middleware would reject those posts, configure it accordingly and say so
in your README.