How can I get $PATH to always include $(pwd)/sub_directory/.bin

If the path ~/dev/project1/node_modules/.bin/ionic exists, and my working directory is ~/dev/project1, I would like to be able to just type ionic and hit enter.

I could include all those subdirectories to PATH but I'm curious if there's a cleaner way. I'm looking to add some magic so my path always includes that subdirectory relative to whatever my current working directory is.

Bonus points if you can make it search all parent directories for that subdirectory and add all of them to the path.

Thanks!