Modular has made great strides towards bringing full-fledged debugging support for the Mojo programming language in LLDB. Our commitment goes beyond making basic debugging work; we aspire to place debugging in a first-class status for Mojo. We’ll dive into the unique technical challenges we’ve faced in this journey, and how we extended MLIR and LLDB for proper language debugging using DWARF, highlighting our open-source contributions. We’ll also explore the approach we are taking to create a great user-centric debugging experience, focusing first on VS Code.