A programming language framework may be enhanced to provide for dynamic validation. Dynamic validation allows the validator function for any variable to be selected at runtime rather than statically declared at programming-time. Instead of annotating a variable with an annotation that refers to a specific validator function or constraint type, programmers can annotate a variable with an annotation that indicates that the validator function will be selected dynamically at runtime. When a runtime instance of the variable is created, the programming language framework may identify the dynamic validation annotation on the variable, and then use the runtime values in the variable to determine which validator function(s) should be used.