Ask HN: Are you using AWS Lambda in production?

I am building a new type of backend as a service solution and would like to weigh your opinion on existing server less solutions. Are you using AWS Lambda or Azure functions or other offerings in production? Are you using Lambda for your main backend or just for event driven support services like consolidating logs or resizing image files? How much is your average monthly spent on Serverless services? What are the main considerations for moving towards Serverless (Cost/Maintenance)?