1. Change some files
2. Build the executable for your project ./_build/default/bin/foo.exe
3. Manually revert ./_build/default/bin/foo.exe in your source control
4. Running build again does not re-update foo.exe to be based off of the current source (bug)

I guess something is cached that causes dune to not update the executable when you've manually reverted it. Workaround right now is to do some sort of change in the source, build, then revert the change, then build.

(@jordwalke This is the bug I was talking about)