The design and implementation of complex software systems inherently spans multiple levels of abstractions. The concepts of each level of abstractions and their interplay are represented by formal languages that are either implicitly known or explicitly defined. Achieving high productivity in software development and maintenance is thus strongly connected with ruling the complexity of multi-level language design and evolution. This paper explains the necessity for automating multi-level language evolution, discusses its challenges and proposes concepts as well as a prototypical tool that support the incremental co-evolution of a staged language and program generation architecture. This approach reduces the cost of language maintenance and paves the ground for an incremental and bottom-up oriented way of developing domain specific languages.