1) PHP OOP, MVC programming. Ensures fast start and easy extention for the application. 2) MySQL architecture. PDO interface. Large data operation. 3) Data scraping, grabbing. Get a lot of required data from web automatically. 4) Files processing (parsing, compilation): CSV, DOC, PDF etc. Import/export your data. 5) Web service APIs implementation: SOAP, REST, XML, JSON. Payment gateways, geolocation, trading bots etc. 6) Custom CMS, CRM. Control of leads, orders, website contents etc. 7) Traffic analyze. Statistics, dashboards etc. 8) JavaScript/JQuery powered UI. Browser side and asynchronous data processing, 9) Email, fax, SMS sending automation. Easy requests, notifications, polls etc. 10) PSR coding standards. Commenting the code is taking extra time, but if required it's not a problem. 11) Code optimization. Sometimes a good functionality is too slow or server resource consuming. Solution is often possible. 12) Distributed systems. Control many websites from one CMS, using separated file server or database server. 13) Data processing. Filter, sorting, validation, aggregation etc. 14) Search functions. Autocomplete ready solutions. 15) Web service security implementation/improvement. Application-level. Protection against SQL injection, XSS and request forgery/spoofing. Captcha ready solutions.