In my spare time I have been mucking around with 2 big Functions-as-a-Service (FaaS) offerings, AWS Lambda and Azure Functions. I've been meaning to write up a “The state of serverless development” post, but today Mike Roberts updated his overview of the market for serverless computing and it's far more thorough than I could ever be.
The whole thing is well worth a read if you're interested in the area, but these parts (emphasis mine) really resonated with me:
Serverless is not the correct approach for every problem, so be wary of anyone who says it will replace all of your existing architectures. Be careful if you take the plunge into Serverless systems now, especially in the FaaS realm. While there are riches — of scaling and saved deployment effort — to be plundered, there also be dragons — of debugging and monitoring — lurking right around the next corner.
Serverless services, and our understanding of how to use them, are today (May 2018) in the “slightly awkward teenage years” of maturity. There will be many advances in the field over the coming years, and it will be fascinating to see how Serverless fits into our architectural toolkit.
This is exactly right in my experience.
Lambda and Azure Functions let you write+deploy code quickly without an infrastructure team and an execution platform. However, the developer experience is often a big step backwards – Lambda doesn't offer any remote debugging support, and just running+debugging functions locally is a big pain. Azure is further ahead in debugging, but things are still more complicated and less reliable than when debugging traditional apps. Integration testing is difficult on both platforms.
The benefits of serverless platforms outweigh the costs for my small hobby projects, but they almost certainly would not for larger-scale development in in most organizations.
The good news is that this area is maturing very rapidly; the tooling for .NET Azure Functions is much better today than it was 1 year ago. Serverless might not be right for enterprise development today, but just a few years from now a lot of these rough edges will be a distant memory.