LoadError dm-migrations (RPi)

[NullVibes]

Attempting to start blue_hydra on an RPi, I run into the error "cannot load such a file -- dm-migrations". I started with Ruby 2.7.0 (same error) but then installed Ruby 2.5.0 with bundler 2.1.2 according to the error output. Each run, same error. If I run gem list, I see that the dm-migrations (1.2.0) gem is installed, but it's still throwing the LoadError.

[NullVibes]

Issue Resolved (?)
Ran: sudo bundle exec ./bin/blue_hydra
An error returned for a missing gem -> rake, so installed that.
Ran: sudo bundle install (even though it's not recommended)

Then sudo bundle exec ./bin/blue_hydra worked! Lots of BT/BTLE goodness returned.
( sudo ./bin/blue_hydra command also now works.)

[NullVibes]

Thank you, Erin Germ, for documenting your process!

http://eringerm.com/md/02%20-%20install%20and%20configure%20blue_hydra%20on%20pi.txt