This is a Magento 2 module example on how to add custom attribute into a Customer via install script.
- Copy the content of the repo to the app/code/Dev/CustomerAttribute
- Run command: php bin/magento setup:upgrade
- Run command: php bin/magento setup:static-content:deploy (Use -f for force deploy on 2.2.x or later)
- Now flush cache: php bin/magento cache:flush
If you encounter any problems or bugs, please open an issue on GitHub.