public APIs for outof.coffee
Install protoc for your OS. How to do that is out of scope.
You also need go 1.12.x or higher. 1.13.x will be the minimum once it is GA.
go get -u github.com/grpc-ecosystem/grpc-gateway/protoc-gen-grpc-gateway
go get -u github.com/grpc-ecosystem/grpc-gateway/protoc-gen-swagger
go get -u github.com/golang/protobuf/protoc-gen-go
make all