I am in my late 30s, European, with kids, can't say I am a successful engineer at this age. Most of my life I did CRUD/backend services initially Python, later Go.
As I get older, I feel urgency to be an expert in area and go deeper, but I am still storing/pulling data from DB, transforming and presenting through REST/gRPC APIs.
Ideally, I would love to have a single area to which I can dedicate rest of my professional career, be it ML, ML Ops, Data engineering, Infra guy (AWS, Azure or GCP), maybe a security?
Any recommendations?
UPDATE: Thanks everyone, so many valuable insights are shared.
The flip side to a high-reward path is high risk. ML Ops is cool now, but ten years ago blockchain was cool. That hasn't really played out the way a lot of people thought it would, and those who went all-in may have wasted their time.
Then there are passion areas that are intrinsically cool, and the number of people willing to do this work will always exceed the number of jobs. Think video games.
You say you have kids, and in that case a low-reward, low-risk career was probably the prudent path to take. When people depend on you, the risk of failure is magnified, a lot.
The "correct" reaction to a midlife crisis is almost a trope now: you have it pretty good, don't rock the boat, don't screw things up.
If you have free time (I don't know how old your kids are) you can use that to explore new areas of technology. Just remember the grass is only greener when it's fertilized with BS, every passion eventually becomes just a job, and work does not define you.