During the Codemotion Madrid 2019 conference, Vicenç García Altés presented the talk "Operational Serverless". We asked Vicenç these questions: Is serverless still in a “prototypical” stage? Or are we ready to use such paradigm in production, for big commercial projects? In your opinion, what technologies, frameworks and/or programming languages do better support the implementation of serverless applications? Based on your experience, what are the major difficulties in making a serverless application? Which basic software design principles should everyone approaching serverless implementations know and apply? Do you see any significant competitor to AWS Lambda presently?