3 ways to run Spring (the Rails app preloader) and how to disable it

spring ...

The most obvious way to use spring is to call it explicitly:

spring rails console
spring rake db:migrate

Binstubs

Binstubs are wrapper scripts around executables. In Rails they live inside bin/. If you run spring binstub --all, your binstubs will be using Spring.

bin/rails console
bin/rake db:migrate

bundle exec rails ...

Bundle exec is inconsistent when it comes to spring. Some commands will use it, some won't.

bundle exec rails console # starts Spring
bundle exec rake # does not start Spring

Disabling Spring

You can temporarily disable Spring by setting the environment variable DISABLE_SPRING. Obviously, this does not work when calling Spring explicitly.