One commit rather than two because they are not independent: the UI's
`enable` had the controller's as its literal default, so moving the
controller alone would leave the UI's default naming an option that no
longer exists.
The UI keeps that derivation in its new home — it is a view onto the
controller's state and reaches it over that daemon's unix socket, so the
host running the controller is the host that can serve it.
Three spellings had to move together for the UI, not one: the `default`,
the `defaultText` shown in the options doc, and the description prose
that names the old path in words. A grep for the option path finds the
first two.
The sweep also reached outside nix: `swarm-controller`'s crate README and
its `//!` module doc both named the option, as did this repo's own
CLAUDE.md and four pages under docs/. An option's name is API, and its
documentation lives wherever someone thought to write it down.
Every other check in nix/checks.nix is a Rust derivation, so a
.nix-only diff moves no hash, the whole set is cache hits, and
`nix flake check` reports green without evaluating what changed.
`checks.module-eval` is one derivation holding a table of cases, each
named by the PROPERTY it defends. Its builder text embeds the evaluated
results, so the derivation's hash is a function of them: a nix change
that flips a property rebuilds the check and fails in the builder,
naming that property.
PROVEN, not assumed — the mechanism was executed before the cases were
written. Same expression with one property true vs false:
drvPath true -> 5v11mnbv…-module-eval.drv
drvPath false -> ivm3dvv8…-module-eval.drv (differs)
build false -> FAILS, stderr names the property
and the table itself was mutation-tested: inverting one case's
expectation gives `FAILED: a hive that has not opted into all-local
runs no swarm controller / module-eval: 1 of 5 properties broke`. A
check that cannot go red on a broken tree is not evidence.
Cases are named by property and never by ticket: a case named after the
ticket that prompted it has that ticket's lifetime; one named after the
property lives as long as the property does.
⚠️ It evaluates, it does not execute. Where the artifact is a command
line, a request or a certificate, a value assertion cannot stand in —
that is written into the file's header, because the gap is exactly what
made two earlier outages evaluable-but-broken.
