I'm an older (than you!) developer, but I have no special resources related to that. But for what it's worth, here's my experience. I've found that nothing is really much different being an older developer compared to being a younger one, aside from two things: I have a lower tolerance for bullshit, and I have a much better handle on what my time is actually worth to employers. While ageism is certainly a thing that…
I'm in my mid-30s and facing the reality that I do not want to be a manager, but have a hard time picturing myself coding into my 60s. I'd be curious to hear more about what in your eyes separates "certain parts of our industry" that aren't suitable for older devs from those that offer good jobs which pay what you're worth. What kind of attributes would you look for in a company or product if you were searching for a…
This is very much broad-brushing and there are plenty of exceptions, but in general I've found that startups, FAANG-style companies, and companies that seem more focused on making products as a vehicle for using new technologies (as opposed to using appropriate technologies to make better products) tend to have a greater prejudice in favor of younger developers.
If such a company interests me, I'll absolutely apply to work for them -- but I don't really expect I'll hear back from them past the initial interview.
Although I have had good experiences as an older dev working for software companies, I've found that I have the best experiences working for companies that aren't overtly software. My current job, for instance, is at a company that makes industrial equipment. The software isn't the product, it's one of the components that makes the products work. It involves several currently-fashionable technologies, though, such as machine learning, so it's not like I'm working in a technological backwater.
My general approach, really, is more about setting proper expectations in my own mind rather than trying to pinpoint "older dev friendly" companies. If a company is doing something interesting, and appears to be the sort of place I'd enjoy working at, I'll toss my hat in the ring even if I suspect they'd consider me to be too old. I just won't get my hopes up with them.
I've also found that a big indicator is when I physically visit their offices and see the makeup of the other devs working there. Even a casual glance can reveal much in terms of how youth-oriented the company is. If I'm the oldest person in the building, they're probably not going to hire me.
I don't know if any of this helps. I'm a believer in not prejudging things too hard and don't really let my perception of their age culture be a significant factor in my decision-making. There are no hard lines here, and I have been hired and welcomed into companies where I was the oldest dev in the place by a large margin.