Limits on Time Zone Representation in brew info JSON

Answer

Homebrew’s brew info --json=v2 always emits created_at and updated_at as UTC ISO‑8601 strings (ending with Z). There is currently no flag to change this to the user’s local time zone, and no public roadmap item promises such a feature in the near term. Until a native option appears, the safest approach is to perform a client‑side conversion in your consuming code.

Why this is the case

• All releases up to 2026-10-09 use UTC for these fields; the Homebrew repository has no open issue or PR that introduces a local‑time flag.
• The JSON schema defines these fields as strings, so adding an offset or alternate representation would be a breaking change without a clear deprecation path.
• Homebrew’s release cycle is community‑driven; feature proposals must surface as GitHub issues or PRs, and none currently propose a local‑time flag.

Practical recommendation

1. Verify the current format:

   brew info  --json=v2 | jq '.[0].created_at'
   # Expected output: "2023-08-15T12:34:56Z"
   

2. In your client code, parse the string as UTC and format it to the desired zone. For example, in JavaScript:

   const dt = new Date(json.created_at); // parsed as UTC
   const local = dt.toLocaleString();
   

   Or in Python:

   from datetime import datetime, timezone
   created = datetime.fromisoformat(json['created_at'].replace('Z', '+00:00'))
   local = created.astimezone()  # local system zone
   

3. Wrap the conversion in a helper so future changes (e.g., a new flag) can be handled gracefully. Detect the presence of a hypothetical --local-time flag by checking the JSON schema for a new field or by attempting to call brew info --help and parsing the output.

What to do if you need confirmation about a future flag

If you suspect a change is imminent or want to influence the roadmap, open a GitHub issue in the Homebrew repo asking for clarification on a local‑time option. The maintainers will typically respond if such a feature is planned.