I wanted to post this here to hopefully help anyone else.
Bootstrap v4 was calling for popper.js at app.com/popper.js - to which I was unhappy with and unwilling to put a script dependency in the root directory of my app.
I tried shim via require js.
paths: { "jquery": "lib/jquery.min", "popper": "lib/popper.min" }
shim: { "bootstrap": { deps: [ "jquery", "popper"], exports: "bootstrap" }
No help. I was still getting a console error referring to the call to app.com/popper.js.
After some research I came upon some quick fixes like double require calls assigning a global variable to window.Popper. Seemed really hacky and not very amd like.
I was really confused because on the website ("bootstrap.com/download") the paragraph about downloading bootstrap.js said that the dependencies wouldn't be included in the package. A google search (the lucky 20 or 30th) lead me to the bootstrap documentation mentioning that the "bootstrap.bundle.min.js" in the official downloaded package had popper.js packaged with it and without jquery. Perfect.
"bootstrap.com/contents": Bundled JS files (bootstrap.bundle.js and minified bootstrap.bundle.min.js) include Popper, but not jQuery.
So I added it to my library. Changed the name ( "bootstrap.bundle.min.js" -> "bootstrap.min" ), created a path for bootstrap and a shim for jquery. Seems to have worked for me.