Today I updated the fp-listen and freshports daemons. These are the scripts which invalidate the cache and process incoming commits, respectively.
No code changes were made, just the installations directories.
Previously, this code when into /var/service but now they go into /usr/local/libexec/freshports-service and I create a symlink from /var/service as as required.
This confirms to the standard method described at https://cr.yp.to/daemontools/faq/create.html for adding/removing services.