Template Binary Sensors after HA restart

To avoid binary sensors firing at startup, you can make your automations follow an inverted binary sensor:

- platform: template
  sensors:
    contact_inverted:
      value_template: >-
         {{ is_state('binary_sensor.contact', 'off') }}
      device_class: door

Idea comes from ☔ DIY Zigbee rain gauge - #96 by oet