I am curious why you're transitioning off from Datadog?
A monitoring solution based on Grafana and Prometheus tends to have a high initial setup cost plus on-going maintenance since it's self-hosted and lacks some of the features that Datadog offers out of the box (alert customization for instance).
I have both worked with and interviewed people in their 40s when I worked at a FAANG. Despite what's advertised by HR, culture tends to be org/team-dependent at bigger tech companies. I believe that you should be more concerned about culture fit which is something you can assess during the interview. If you decide to interview for an individual contributor position, I recommend that you brush up on algorithms. You can either target a company on LeetCode or go through a generic list of problems (here is the one I use https://theinterviewlist.com)
In addition to the resources others have suggested here I recommend going through this list of problems that I put together for the coding portion of FAANG interviews: https://theinterviewlist.com
The salaries shown on H1BPay are the salaries that the company promises to pay or is currently paying the H-1B applicant.
There are 3 common cases of when the paperwork is filed. First, foreign students who graduated from American universities in certain fields can work for a certain period of time after which they can transition to H-1B. So the salary is pretty much what they are paid when the application was filed which is somewhere between 1 and 27 months. Second, people hired from overseas or within the US who aren't new graduates and don't have a current H-1B visa. Their salary would be what the company offered to get the talent. The third case is when you transfer you H-1B visa where an application is not required so there is no change to the salary in the application.
Looking at glassdoor.com and my personal experience, salaries are much lower than what people are claiming on HN
A major problem with Glassdoor salaries is the absence of a date range. The salaries they show is the average over the period of time starting when they started collecting salaries. So yes the salaries on Glassdoor tend to be lower than the current average.
A lot (too many) people on HN are claiming $200k base salary per year as being totally normal.
I agree. It is pretty high. My own reference for base salaries is my own website where I collect H-1B salaries. We also have an option to only show the salary distribution starting on a given year. For instance, for a software engineer at FB, the average base salary is $149k if you only include salaries reported after 2015 [1]. At Netflix however, Sr. Software Engineers make $200k on average[2].