react developer front end developer nextjs seo optimization web design web programming freelancer for headless ecommerce sites react recoil state management freelancer for openai integration technical seo services node.js development react development vue.js development website performance optimization flask development react native web ruby on rails hire software developer database https://daltonbdgil.blogdigy.com/the-best-side-of-software-developer-kpi-template-55436073