The record claimed a version reaches a machine as an ordinary archive with
nothing new needed. Two things it needs do not exist: no toolchain can compile
the host (the list is typescript and python, and the control plane, also Go, is
built as an image from a Dockerfile instead), and nothing interpolates a built
version into a resource path, so nothing can ask for .../versions/<version>/.
The decision, the options weighed and every consequence stand — the host half is
merged and tested. What was understated was the cost, so it is corrected in place
and dated rather than superseded.
The supervision was already right — a clean exit means the host stood aside and
the launcher runs what is on disk, failures are counted, and a rollback happens
at the limit. Two things made it dead code: nothing told the running host a
successor was waiting, and the rollback resolved its known-good version through
pacman, which no machine here uses and which two of three operating systems do
not have.
Keeping a version rather than a path was the clue. Versions live side by side in
directories named for them; the newest runs; the running one stands aside between
reconciles; a reconcile that completes records itself and retires what is older
than its predecessor; rollback starts that predecessor. No new resource kind and
nothing new on the bus — an archive already fetches by digest, and the path
written is never the path executing.
Answers issue 142.
jschoubben