Start with exact inputs
A published version, verified integrity and one sealed dependency snapshot shared across the runtime matrix.
The public runtime lab
Know what loads.
See the evidence.
Test an exact npm package across Node.js, Bun and Deno. Inspect loading results, coverage and the environment behind every observation.
Public npm packages. No account required.
Observe each runtime
Independent import and require checks, then bounded subpath batches. Scripts stay disabled and execution stays offline.
Understand the limits
Inspect failures, incomplete coverage and pinned environments. Loading success does not prove functional correctness.
Open source by design
Bring the lab to your own execution host.
The same engine powers local checks and hosted evidence.
Read the CLI setup guide →compatlab check [email protected] --json