I tried building pgagent on Windows with Boost-1.69.0 and cmake-3.30.x, but it was not able to detect Boost libraries.
So, I dig into it and here are my findings:
FindBoost.cmake present in <pgagent-source>/cmake is not working for Boost-1.69.0 with cmake-3.30.x.
When I replaced it with the FindBoost.cmake from cmake-3.30.4, it worked fine.
Also, along with this I needed to copy FindPackageHandleStandardArgs.cmake and FindPackageMessage.cmake to <pgagent-source>/cmake/ to make it work.
https://github.com/Kitware/CMake/blob/v3.30.4/Modules/FindBoost.cmake
https://github.com/Kitware/CMake/blob/v3.30.4/Modules/FindPackageHandleStandardArgs.cmake
https://github.com/Kitware/CMake/blob/v3.30.4/Modules/FindPackageMessage.cmake