https://mango.pdf.zone/finding-former-australian-prime-minis...
If traveling into the US from overseas, you need to disclose a whole bunch of info to get your ESTA, and for the flight itself there's APIS: https://en.wikipedia.org/wiki/Advance_Passenger_Information_...
And for any flight that even overflies the US, there's Secure Flight:
So my takeaway is that for enhanced privacy I should try to book flights with travel agencies instead of directly with airlines. Is the advice still applicable or is it nowadays futile?
What's in a Passenger Name Record (PNR)? - https://news.ycombinator.com/item?id=6037279 - July 2013 (2 comments)
The protocols are heavily documented in many ways, but we also had an on-site pair of experts on this particular mainframe network, as an information resource, and we needed them. And I still had to reverse-engineer some semantics or format from real-world protocol captures, and freeze that knowledge in unit tests.
There was one opcode that initially sounded simple. IIRC, linguistically, it turned out be closer to an eval than an echo.
This kind of work, carefully interoperating with critical legacy systems, can be more interesting and positive than serving cat pictures and running surveillance trackers in exactly the architecture memorized for a Design Interview. But if you do anything involving mainframes, and then want to go back to startups or Big Tech, I wouldn't put the toxic keyword "mainframe" on your techbro resume; use euphemisms like "global financial system" instead. Also, you should say that you "disrupted" it; though disrupting a critical system is not usually considered a positive achievement in other circles.