old_contents: import dj_database_url
  
  from . import env_var
  from .base import *
  
  
  # Application settings
  DOMAIN = 'boards-backend-staging.herokuapp.com'
  APPLICATION_URL = '{}://{}'.format(HTTP_PROTOCOL, DOMAIN)
  
  # Debug Mode
  DEBUG = env_var('DEBUG', False)
  TEMPLATE_DEBUG = env_var('TEMPLATE_DEBUG', False)
  
  # Installed Apps
  INSTALLED_APPS += (
      'djrill',
  )
  
  # Honor the 'X-Forwarded-Proto' header for request.is_secure()
  SECURE_PROXY_SSL_HEADER = ('HTTP_X_FORWARDED_PROTO', 'https')
  
  # Allow all host headers
  ALLOWED_HOSTS = ['*']
  
  # Database
  DATABASES = {
      'default': dj_database_url.config()
  }
  
  # Email settings
  EMAIL_BACKEND = "djrill.mail.backends.djrill.DjrillBackend"
  MANDRILL_API_KEY = os.getenv('MANDRILL_API_KEY')
  
  
  # Static asset settings
  STATIC_ROOT = 'staticfiles'
  STATIC_URL = '/static/'
  STATICFILES_DIRS = (
      os.path.join(BASE_DIR, 'static'),
  )
  
  
  # Django REST framework
  REST_FRAMEWORK['DEFAULT_AUTHENTICATION_CLASSES'] = (
      'blimp_boards.users.authentication.JWTAuthentication',
      'rest_framework.authentication.SessionAuthentication',
  )
  
  REST_FRAMEWORK['DEFAULT_RENDERER_CLASSES'] = (
      'rest_framework.renderers.JSONRenderer',
      'rest_framework.renderers.BrowsableAPIRenderer',
  )
  
  
  # boards-web
  BOARDS_WEB_STATIC_URL = os.getenv('BOARDS_WEB_STATIC_URL')
  BOARDS_WEB_CLIENT_VERSION = os.getenv('BOARDS_WEB_CLIENT_VERSION')
  
  
  # Logging
  LOGGING = {
      "version": 1,
      "disable_existing_loggers": False,
      "handlers": {
          "console": {
              "level": "INFO",
              "class": "logging.StreamHandler",
          },
      },
      "loggers": {
          "django": {
              "handlers": ["console"],
          }
      }
  }
  
new_contents: import dj_database_url
  
  from . import env_var
  from .base import *
  
  
  # Application settings
  DOMAIN = 'boards-backend-staging.herokuapp.com'
  APPLICATION_URL = '{}://{}'.format(HTTP_PROTOCOL, DOMAIN)
  
  # Debug Mode
  DEBUG = env_var('DEBUG', False)
  TEMPLATE_DEBUG = env_var('TEMPLATE_DEBUG', False)
  
  # Installed Apps
  INSTALLED_APPS += (
      'djrill',
  )
  
  # Honor the 'X-Forwarded-Proto' header for request.is_secure()
  SECURE_PROXY_SSL_HEADER = ('HTTP_X_FORWARDED_PROTO', 'https')
  
  # Allow all host headers
  ALLOWED_HOSTS = ['*']
  
  # Database
  DATABASES = {
      'default': dj_database_url.config()
  }
  
  # Email settings
  EMAIL_BACKEND = "djrill.mail.backends.djrill.DjrillBackend"
  MANDRILL_API_KEY = os.getenv('MANDRILL_API_KEY')
  DEFAULT_FROM_EMAIL = os.getenv('DEFAULT_FROM_EMAIL')
  
  
  # Static asset settings
  STATIC_ROOT = 'staticfiles'
  STATIC_URL = '/static/'
  STATICFILES_DIRS = (
      os.path.join(BASE_DIR, 'static'),
  )
  
  
  # Django REST framework
  REST_FRAMEWORK['DEFAULT_AUTHENTICATION_CLASSES'] = (
      'blimp_boards.users.authentication.JWTAuthentication',
      'rest_framework.authentication.SessionAuthentication',
  )
  
  REST_FRAMEWORK['DEFAULT_RENDERER_CLASSES'] = (
      'rest_framework.renderers.JSONRenderer',
      'rest_framework.renderers.BrowsableAPIRenderer',
  )
  
  
  # boards-web
  BOARDS_WEB_STATIC_URL = os.getenv('BOARDS_WEB_STATIC_URL')
  BOARDS_WEB_CLIENT_VERSION = os.getenv('BOARDS_WEB_CLIENT_VERSION')
  
  
  # Logging
  LOGGING = {
      "version": 1,
      "disable_existing_loggers": False,
      "handlers": {
          "console": {
              "level": "INFO",
              "class": "logging.StreamHandler",
          },
      },
      "loggers": {
          "django": {
              "handlers": ["console"],
          }
      }
  }
  
subject: set DEFAULT_FROM_EMAIL from env in staging