by Felix Arntz on WordPress.org
Implements JSON feeds following the official JSON feed specification by using the WordPress REST API.

Example JSON feed response generated by the plugin
Implements JSON feeds following the official JSON feed specification by using the WordPress REST API. By default, only a JSON feed for regular posts is added. This can be easily customized to also provide JSON feeds for e.g. certain custom post types.
/wp-json/feed/v1/posts).show_json_feed argument when registering the post type.