Dendrite and maghemite do not build mac binaries for dpd, swadm, and mgd. To work around this, I wrote a script I've been passing around to all macOS users in secret. This script checks out the right commit locally and builds those binaries from source. @davepacheco suggested this could just be part of the normal install xtask. Claude got it done in about 5 minutes and it appears to work quite well.

Differences from the original script to not assume anything about your computer:

1. Commit-hash based binary caching is portable — cache lives in out/.build-cache/{project}/{commit}/
2. Clone dendrite and maghemite from scratch in temp dirs instead of assuming they are already cloned next to omicron