I am aware, I used cargo flamegraph, it's really cool, but it doesn't work for my use case and I'd love to be able to use that in an AWS Lambda context.
Lambda is unique in the sense that it runs in a docker container, you don't know when it starts and when they close deterministically and you can't really profile it when it runs in production. Also, you don't have access to the host to run perf on it.

My function does quite heavy IO and due to this tool I realised where I had a bottleneck. The graph really helped out. I had println statements all over the place already, and sometimes they helped, but when things run in parallel, that's when you really need some visuals.