* **[Environments](environments.md):** Group data between environments (e.g. dev, staging, prod) within a project.
* **[Sampling](sampling.md):** Discard some traces or spans to manage data storage and analysis efficiently, including setting up the `trace_sample_rate`.
* **[Scrubbing](scrubbing.md):** Automatically redact sensitive information from your logs and spans using customizable patterns and callbacks.
* **[Testing](testing.md):** Verify your application's logging and span tracking with Logfire's testing utilities, ensuring accurate data capture and observability.
* **[Backfill](backfill.md):** Recover lost data and bulk load historical data into Logfire with the `logfire backfill` command, ensuring data continuity.
* **[Creating Write Tokens](creating-write-tokens.md):** Generate and manage multiple write tokens for different services.
* **[Using Read Tokens](query-api.md):** Generate and manage read tokens for programmatic querying of your Logfire data.
