Launchpad does not support passing options to snapcraft right now: https://bugs.launchpad.net/launchpad/+bug/1949989 If this gets resolved, please consider adding similar support to snapcraft's remote-build feature. At the moment, this would be necessary to build with the kde-neon extension on core20 by passing "--enable-experimental-extensions". I'm sure similar cases will pop up in the future, so being able to pass (at least some) options to snapcraft would be very beneficial.