Given a 3 week deadline, I just built a mobile app using #fsharp and #xamarinforms for emergency responders.

I applied techniques I learned from @ScottWlaschin 's book, @debasishg 's book, and @IDesign_inc 's book. The mobile solution is partitioned into two sub-domains in which each layer (UI, Domain, Data Store) relies on their relative specification library. A specification library exposes business terminology as record or choice types and business policies as function types.