@twobob: Yep, I don't set includedir, and am indeed overriding CPPFLAGS when building stuff that depends on ncurses, like htop

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includedir should default to ${prefix}/include, and prefix defaults to /usr, so just adapt that to your setup

(AFAICT, /home/usr/include or /home/include, depending on how you set stuff up).
While we're talking about paths, I also don't set a custom terminfo path, because I'm not deploying the lib to my Kindle, I'm just using it to link stuff against it. So, to fix the crappy terminfo db available on the Kindle, I ship one with usbnetwork, and hardcode the TERMINFO env var to point to it in the apps I care about (htop).