WP Advanced Custom Fields - Save and Load via JSON

acf-save-load.php

<?php
/**
 * ACF Custom Fields - Save and Load
 *
 * When ACF fields are added or updated this will save the output to JSON
 * where they can be version controlled and loaded on Production sites.
 * For best usage the production database should not contain any ACF 
 * in the database.
 *
 * @package 
 */

function my_acf_json_save_point( $path ) {
  // update path
  $path = get_stylesheet_directory() . '/custom-fields';
  // return
  return $path;
}

add_filter('acf/settings/save_json', 'my_acf_json_save_point');

function my_acf_json_load_point( $paths ) {
  // remove original path (optional)
  unset($paths[0]);
  // append path
  $paths[] = get_stylesheet_directory() . '/custom-fields';
  // return
  return $paths;
}

add_filter('acf/settings/load_json', 'my_acf_json_load_point');

Create a separate file include file that gets added to functions.php like so, require get_template_directory() . '/inc/acf.php';