A .NET All Versions Developer designs, develops, tests, and deploys software applications using various versions of Microsoft's .NET framework. They use languages like C#, F#, or VB.NET to build web, desktop, mobile, and cloud-based applications. They interact with databases, implement APIs, and ensure security and data protection. They troubleshoot and debug applications, optimize systems for performance and scalability. They also stay updated with evolving .NET technologies, migrating older .NET applications to newer versions when necessary. Additionally, they collaborate with teams, understand client requirements, and contribute to the entire application lifecycle.