Need to prevent Heroku from installing some gems that are NOT in the test or development environments? For example, we use the
memcached gem which won't compile on Heroku, but it still needs to run in some non-Heroku production environments.
If you want to do the same, first set a
HEROKU environment variable:
heroku config:add HEROKU=true
Then add code like this in your
# Don't install these gems on Heroku group ENV['HEROKU'] ? :test : :default do gem 'memcached', '1.3.2' end
Now the environment variables are not normally enabled during slug compilation (when it installs the gems), but you can enable that!
heroku labs:enable user-env-compile
For more info: https://devcenter.heroku.com/articles/labs-user-env-compile