freelancer for app refactoring and cleanup back end developer react compiler optimization freelancer for multi-tenant saas apps react devtools ai assistant dotnet developer react micro-frontends freelancer for biometric time tracking zustand react state library freelancer for machine learning integration react query data fetching python web development web design and https://erickizmud.thezenweb.com/not-known-details-about-software-developer-tools-for-mac-74552072