AWS Lambda made both deployment and development a pain, even though the decision to use that platform for their use-case (a regular API) was just one of the mistakes done by a team that was brainwashed by expensive marketing and then paid the price for having only cheap and proprietary tools for development and deployment at their disposal.

If only AWS was open source, then we could have deployed our own cognito and lambda instances to develop locally, instead of the open source mocks that didn't pass the field test in my opinion: lack of quality, maintenance, documentation were critical factors.