PHP : - Candidate should have very good knowledge, experience and must have hands on the below mentioned technology
API design and development
Server-side languages like PHP, Strong experience in Core PHP, CMS (wordpress, Magento, joomla, magento, shopify etc) and Frameworks(Zend, Symfony , codeigniter, cakephp, laravel, yii etc) with version control software like SVN, CVS, or Git.
Database technologies like MySQL, Oracle, PostgreSQL, and MongoDB.
Web server technologies like Node.js, etc.
Frameworks related to their server-side language of choice like: Express.js
CSS preprocessors like Sass or LESS.
Libraries like jQuery or Backbone.js
Front-end (CSS) frameworks like Foundation or Bootstrap.