Recommended next stage: Implement Error Propagation (?) operator as Phase 1.5 foundation (2-3 week timeline). This is the simplest P0 feature that validates the newly-built plugin architecture while delivering immediate user value - reducing error handling boilerplate by 60%. The implementation establishes AST transformation patterns that all future features will reuse, proving Dingo's value proposition quickly before tackling more complex features like Result types or sum types.
