Worked on the jdx/mise repository to address reliability issues in Python virtual environment creation, focusing on backend development and testing using Bash scripting and Rust. Tackled a circular dependency problem by restricting the toolset to Python and UV, which prevented install-time deadlocks when a Go backend was present. Introduced an end-to-end test to ensure stable venv creation and guard against future regressions. Improved the warning system by switching to a warn-once approach and enhancing message clarity, reducing log noise while maintaining actionable feedback for missing Python versions. These changes contributed to more robust environment setup and continuous integration workflows.