Do tests exist? Run the test command. Do they pass?
What is the ratio of test files to source files? Below 0.3 = undertested.
Are there integration tests or just unit tests?
Minute 5-6: Dependency Health
When was package.json/requirements.txt last updated?
Are there known vulnerabilities? Run npm audit or equivalent.
How many dependencies? 200+ in a Node project = dependency bloat.
Minute 7-8: Architecture Signals
Is there a clear directory structure or is everything in /src?
Are there consistent patterns (services, controllers, models) or every-file-for-itself?
How deep is the nesting? 5+ levels deep = likely over-engineering.
Minute 9-10: Documentation and CI
Does a README exist and is it current?
Is there a CI pipeline? Does it run tests on every PR?
Are there any CONTRIBUTING or ARCHITECTURE docs?
What This Tells You
A healthy codebase has: active commits, descriptive messages, passing tests, current dependencies, consistent patterns, and working CI. An unhealthy one fails on 3+ of these checks.
This is not a comprehensive audit. But in 10 minutes, you can tell whether this team invests in code quality or treats it as an afterthought. And that tells you a lot about what working there will be like.
The Deeper Audit
If you have more than 10 minutes — say, a 1-hour deep dive — add these checks:
Architecture quality:
Is there a clear separation between business logic and infrastructure?
Are database queries centralized or scattered throughout controllers?
Is there a consistent error handling pattern?
Team health signals:
How many open PRs? More than 2x the team size = review bottleneck
Average PR review time? Over 48 hours = process problem
Bus factor: do any critical areas have only 1 contributor in the last 6 months?
AI readiness:
Are there consistent coding patterns AI can learn?
Is the codebase typed? (TypeScript > JavaScript for AI tool effectiveness)
Are commit messages descriptive enough for knowledge extraction?
These signals tell you not just about code quality, but about team dynamics, engineering culture, and how much Understanding Tax you'll pay as a new team member.
Glue automates everything in this checklist and more. Connect a repo and get instant pre-code intelligence — feature maps, dependency health, knowledge distribution, and team activity patterns. What takes 10 minutes manually takes 10 seconds with the right tool.