Suddenly, compiles fail due to:
PackageException: Could not install package ‘ottowinter/ArduinoJson-esphomelib @ 5.13.3’
Manually installing the 6.x version succeeds, but of course esphome won’t compile b/c it expects the 5.x version.
Magically, it’s now fixed. Nothing I did. Guess it was just offline momentarily.