react server components freelancer for supabase postgres apps react concurrent mode freelancer for responsive landing pages fullstack dev website development web design freelancer for multi-language app support jotai state management freelancer for openai integration freelancer for langchain agent apps node.js development react development vue.js development react lazy loading components https://softwaredeveloperssalary61348.develop-blog.com/43646948/everything-about-web-developer-need-coding