When you make localization of website, you need language specific configuration files for the supported languages.
POEditor is a useful SaaS service to make the configuration files easily.
Using POEditor, you can build dictionary of the texts that are used in your website for each supported language.
And can export them into a lot of file types such as JSON format, CSV format etc, as well as can sync up with your Github repository.
The service provides auto translation feature, invitation for contributors etc.
It provides RESTful API to fetch the translation files automatically as well.
For more information, you can check here.