This is a tiny example OCaml project I wrote to go along with a blog-post describing how to configure utop so it knows about your opam packages and binaries for a given OCaml project.
Read the blog post for more information.
To get started run
make compile
If everything worked you should have a runnable executable
_build/euler01. This is of course not the interesting part; got read
the blog post for more information.
To play around with the code in the terminal (not Emacs) run utop and try the following:
#load_rec "impl.cmo";;
Impl.compute ();;