# Guides

> Task-oriented walkthroughs for the jobs an integration does most, with requests, responses and the errors that matter.

Each guide takes one task from start to finish: what you need, the requests in order, what comes back and
which errors to expect. The samples use the environment variables `BATTERYPASS_URL` and
`BATTERYPASS_API_KEY` from the [Quickstart](https://passport.kabin.sh/docs/en/quickstart).

## Public passports

[**Verify a signature offline**](https://passport.kabin.sh/docs/en/guides/verify-signature): Canonicalise the public document, compare the hash and check the Ed25519 signature with the published key.

[**Resolve a QR code**](https://passport.kabin.sh/docs/en/guides/resolve-digital-link): From a scanned GS1 Digital Link to the public passport JSON, or look it up by GTIN and serial number.

## Reading data

[**Sync units**](https://passport.kabin.sh/docs/en/guides/sync-units): Copy units into your system with cursor paging, resume after an interruption and spot changes.

[**Export passports**](https://passport.kabin.sh/docs/en/guides/export-passports): BatteryPass JSON, PDF and QR code of a passport version, and the units as a spreadsheet.

## Reporting data

[**Push condition data**](https://passport.kabin.sh/docs/en/guides/push-condition-data): Send measurements from a battery management system with `updateCondition`.

[**Record lifecycle events**](https://passport.kabin.sh/docs/en/guides/record-lifecycle-events): Report inspections, repairs and other events of a unit, and read its lifecycle.

## Running in production

[**Handle errors and retries**](https://passport.kabin.sh/docs/en/guides/handle-errors): Which answers to retry, backoff with jitter, and what to log.

[**Handle keys securely**](https://passport.kabin.sh/docs/en/guides/secure-key-handling): Where keys live, which scope each system gets, rotation without downtime and what to do after a leak.

Looking for a script to copy? The [Recipes](https://passport.kabin.sh/docs/en/recipes) are short, runnable programs for common jobs.