```ruby
unless [:development, :test].include?(Rails.env.to_sym)
  $mixpanel = Mixpanel::Tracker.new('2e87e79bda898d69197d3623c426be35')
end
```

Make the server work properly
user
```ruby
if defined?(Mixpanel)
  $mixpanel = Mixpanel::Tracker.new('2e87e79bda898d69197d3623c426be35')
end
```
assistant