guard fails on windows

[attobyte]

Guard fails with ERROR - No such file or directory - bin/rails test when running bundle exec guard

Environment

Windows 10
Rails 5.2.2
guard-minitest 2.4.6

My guardfile has guard :minitest, spring: 'bin/rails test', all_on_start: false do

The file bin/rails has #!/usr/bin/env ruby which obiously will not work on Windows.

Several internet posts suggest modifying the guard file to:
guard :minitest, spring: 'rake test', all_on_start: false do
guard :minitest, all_on_start: false do

I went with this option thinking bin/rails script should be ran.
guard :minitest, spring: 'ruby bin/rails test', all_on_start: false do

ruby is in my path on the windows box using a rvm like utility.

Is there a recommended fix that is cross platform supported?