Decision Guardian

If you’ve ever worked on a scaling codebase, you’ve probably experienced "institutional amnesia". A senior engineer builds a highly sensitive system—like a custom database connection pool or core authentication middleware—and documents the reasoning in a wiki or an Architecture Decision Record (ADR). But inevitably, months later, a new developer modifies that code without knowing the documentation exists, and things break. Tools like CODEOWNERS are great for telling you who needs to review a Pull Request, but I needed something that automatically tells the developer why the review matters before they even ask. To solve this, I built Decision Guardian, an open-source tool that shifts teams from passive documentation to active enforcement.

How it works: Instead of hoping developers check the wiki, you document your architectural decisions in a standard Markdown file (e.g., .decispher/decisions.md) right inside your repo. You map these decisions to specific files using glob patterns or advanced JSON rules (like regex or line-ranges). When a developer opens a PR that touches those protected files, Decision Guardian instantly drops a structured comment into the code review giving them the exact context, warnings, and checklists they need before they merge.

Open source Repo -: https://github.com/DecispherHQ/decision-guardian