ChangeGuard: Honest Release Validation

ChangeGuard is an MRI comparison application with clinician-facing review information. Changes to thresholds, comparison rules, or UI wording can change what a user sees. Manual validation is therefore a risky developer workflow: someone can run a small test, forget the full suite, and incorrectly treat that limited result as a release decision. Using IBM Bob 2, I built ChangeGuard Release Check: a cross-platform Python CLI and documented validation workflow for these high-risk changes. The --quick command runs only the focused synthetic comparison tests. Its success message is deliberately honest: “TARGETED CHECK PASSED — full regression suite not run.” The --full command runs the complete repository regression suite and is the only mode that prints “FULL RELEASE CHECK PASSED.” Any non-zero test result is reported as failed, never as ready. The tool uses sys.executable and safe local subprocess execution without shell commands, network calls, LLM calls, package installation, or changes to the clinical decision logic. It reports the selected mode, elapsed time, exit code, and concise test output. The target users are developers maintaining ChangeGuard. Their workflow is now explicit and repeatable: make a scoped change, run focused tests, run the full regression check, visually verify the Streamlit interface, then commit and push. For this release, --quick passed all 26 comparison tests. The full check passed 443 tests with 9 optional tests skipped in 109 seconds. The clinical comparison logic remains deterministic, non-diagnostic, and unchanged. The innovation is not a new medical claim; it is an honest release gate that reduces false confidence, regression risk, and rework in a high-stakes developer workflow.