There have been a smattering of solutions offered over the years for getting rid of bundle exec. To me they all have drawbacks -- they either solve the problem at the wrong layer, involve remembering an extra step, require a manually-managed whitelist, or are messy for some other reason.

• carsomyr/rbenv-bundler
• gma/bundler-exec
• mpapis/rubygems-bundler
• various flavors of bundle exec bash: here's one, here's my own quick experiment that I never used
• various flavors of adding ./bin to your path: David Chelimsky post and the comments on this blog post The last one is my favorite -- it uses native shell and bundler features in a straightforward way. However, it's considered a security risk to have ./bin in your path. Someone could trick you into downloading something that you cd into which has a script in ./bin/ls that deletes your home directory or reads your personal information.

Here is my solution to that. If you are using zsh, you can execute arbitrary shell code whenever cd is invoked. So here, I add ./bin to PATH, but only when there is a Gemfile present. Put this somewhere in your zsh config:

function chpwd {
  if [ -r $PWD/Gemfile ]; then
    export PATH=./bin:${PATH//\.\/bin:}
  else
    regexp-replace PATH '\./bin:' ''
  fi
}

Ta-da! Now you just have to remember to use the --binstubs flag whenever you install new gems. This part could be more smoothly handled by Bunder, I've opened a ticket to begin exploring this issue and might put together a solution sometime.

notes

• There is still a security risk when downloading projects with Gemfile present, but now it's much smaller. An alternative would be to check for .my_special_file instead of Gemfile -- that file would have to have a non-standard name in order to be fully secure. Eventually I want to switch to this even more secure method, but I can't think of an elegant way to pick its name, so I'm sticking with Gemfile :-D.
• if you have something already defined in chpwd, you have to put this code inside the same chpwd -- consecutive chpwds will overwrite each other. This also stops me from making a flexible oh-my-zsh plugin. If anyone knows how to add chpwd behavior without overwriting previous chpwd behavior, let me know!
• It works with foreman too -- foreman run foo will use the correct executable and foreman run which foo shows the correct path. However for some reason foreman run type foo does not -- I guess type starts a fresh environment for some reason?
• Next I would like to automatically prepend everything with foreman run :-D I imagine that will be hackier though. Any ideas?