"Serverless functions are slow" -> not really, only if designed poorly
"DX serverless functions is sub-par" -> where's your proof, again you'll have bad experience as a developer only if you don't know what you're doing. Which I see mainly from people trying to approach building serverless applications by having a container-like mindset and that leads them to bad design choices.
"Serverless functions come with vendor lock in" -> I think most of us are beyond the point of that vendor locking is bad choice. Worse choice is picking a sub-optimal technology with lower performance, higher cost and lesser reliability.
"Cost eventually gets in the way" -> Again, only if you don't know what you're doing and make bad design choices.
When it comes to Web Assembly, I don't see how this is a better choice of technology vs something like Node. In node I have a much wider support of the technology than WA (talk about vendor-locking), I have a proven eco system of libraries, knowledge and a much bigger talent pool to source from. The cold start issue you mentioned on your website, I can tell you first hand, the cold start is not really that big of a problem, not big enough that you would want to switch to a different technology and there are many ways to mitigate the cold start problem.
Just saying, I'm far from convinced that there is a benefit in switching. I would love to see more detailed benchmarks and examples I would be able to replicate than just statements in a blog post.
The database is one of the most important choices you can make. Any database that requires a TCP/IP connection and doesn't work with an HTTP API is out of the picture due to the way lambda functions work with such databases. See more: https://www.webiny.com/blog/using-aws-lambda-to-create-a-mon...
The learning curve for DynamoDB is steep, but nothing that a senior developer can't tackle in a few weeks. It's a worthy skill to have, especially if you work in the AWS ecosystem.
Vendor locking will always be there, but really, don't worry too much about it, especially in the beginning. There are ways to protect yourself by abstracting your business logic and having a layer between how the logic interacts with the underlying serverless service. Later if you do need to move, the move will still be a bit painful, but not as much.
Cold start is not a problem at all if your bundle is not overly big. If needed you can always have a few provisioned concurrency functions.
Cost, benchmarks and similar - checkout this page: https://www.webiny.com/docs/performance-and-load-benchmark/i...
Disclaimer: I'm one of the authors behind Webiny - enterprise serverless CMS. Happy to answer any additional questions. Hope this helps!
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I actually reached out to Wise support and complained about this practice, as this is borderline illegal, a bank is not allowed to behave like this. They said they are doing an internal investigation on what happened and will get back to me within 30 days.
I'm also looking at filing a complaint to Consumer Financial Protection Bureau (CFPB) or similar.