Offline, read-only parity comparison of two complete redacted environment snapshots. It does not switch traffic or deploy.
This walkthrough uses the tool's public README and checked-in example files. Run the command from a repository checkout with Node.js 22+; inspect the source before using it on your own files.
Run the checked-in example
node bin/blue-green-comparator.mjs --root examples/pass --policy policy.json --blue blue.json --green green.json
node bin/blue-green-comparator.mjs --root examples/fail --policy policy.json --blue blue.json --green green.json
npm run checkRead the result
The CLI emits one JSON report: exit 0=pass, 1=fail, 2=incomplete or invalid configuration. Invalid options, root, or policy leave stdout empty. Unreadable or invalid blue/green inputs produce an incomplete report. Input paths are resolved by realpath beneath --root; strict UTF-8 and duplicate decoded JSON keys are enforced. It writes no files.
Where this check stops
Policy ≤65,536 bytes; each snapshot ≤524,288 bytes; ≤1,000 dependencies and ≤1,000 migrations per side; JSON depth ≤16; evaluation deadline 5,000 ms using an injectable monotonic clock. N is accepted and N+1 rejected for each bound. Findings are ordered by UTF-16 code-unit order. This is structural parity of supplied redacted exports, not a live infrastructure audit or proof of runtime equivalence.
Before adapting the command to your own workflow, review the accepted inputs, exit codes and safety boundaries in the README.
Compiled with AI assistance from checked-in public documentation and example scripts. Run the example and review the repository's current documentation before relying on its result.