> ## Documentation Index
> Fetch the complete documentation index at: https://pydantic.dev/llms.txt
> Use this file to discover all available pages before exploring further.

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---

---
title: "Rust Observability with OpenTelemetry | Pydantic Logfire"
description: Instrument any Rust app with OpenTelemetry and Pydantic Logfire. Your existing tracing macros work unchanged, spans and logs arrive in minutes, and you query all of it with SQL.
canonical: https://pydantic.dev/logfire/rust
last-reviewed: "2026-08-16" # Comparison-table trade-offs rewritten; no companion copy change.
---

> Markdown version of [Rust observability with OpenTelemetry](https://pydantic.dev/logfire/rust) — the canonical HTML page.
>
> Site index: [/llms.txt](https://pydantic.dev/llms.txt)

---

# Rust observability with OpenTelemetry

OpenTelemetry-native observability for any Rust app, from the team behind Pydantic. Built on the `tracing` crate, so the instrumentation you already have keeps working, and query all of it with SQL. Free for 10 million spans, logs, and metrics a month.

[Try Logfire free](https://logfire.pydantic.dev/)

## A few lines to your first trace

```bash
cargo add logfire
```

```rust
fn main() -> Result<(), Box<dyn std::error::Error>> {
    // Reads LOGFIRE_TOKEN from the environment. The region is taken from the token.
    let logfire = logfire::configure()
        .send_to_logfire(logfire::config::SendToLogfire::IfTokenPresent)
        .with_service_name("hello-rust")
        .finish()?;

    // The guard flushes and shuts Logfire down when it goes out of scope.
    let _guard = logfire.shutdown_guard();

    logfire::span!("hello").in_scope(|| {
        logfire::info!("Hello world");
    });

    Ok(())
}
```

Set `LOGFIRE_TOKEN` and run. Records are buffered and flushed on shutdown, so keep the guard alive for the life of the process.

## Your existing `tracing` code already works

The Logfire crate is built on [`tracing`](https://docs.rs/tracing) and OpenTelemetry, so this is not a migration. Any library or code already using `tracing` macros sends through Logfire with no changes:

```rust
#[tracing::instrument]
fn my_function(param: &str) {
    // the attribute creates a span, with param as an attribute on it
    tracing::info!("This also appears in Logfire");
}
```

The `log` crate is captured and forwarded too, so dependencies that use `log::info!()` show up without extra configuration.

## Instrument what matters

- **Keep your `tracing` instrumentation.** `#[tracing::instrument]`, `tracing::info!`, and spans from your dependencies all arrive in Logfire. You adopt a backend, not a new instrumentation API.
- **Structured spans, not string logs.** `logfire::span!("process order {order_id}", order_id = order_id)` records a timed unit of work with queryable attributes attached.
- **Async is first class.** Wrap a future with `.instrument(span)` from `tracing::Instrument` so context follows the task across await points.
- **Traces, metrics, and logs in one place.** Dashboards, alerts, and ad-hoc questions over the same OpenTelemetry-native project, all queried with the same SQL.
- **OpenTelemetry-native, no lock-in.** Prefer raw OpenTelemetry? The standard OTel SDK works instead of the `logfire` crate, and you can export the same data elsewhere or self-host without touching your instrumentation.

**What lands in Logfire:**

- your `#[tracing::instrument]` functions, with their arguments attached
- every `tracing` event your code and dependencies emit
- nesting that follows the call tree, including across `await`
- a failed lookup, marked red at the span that failed

## Query your telemetry with SQL

```sql
select
  span_name,
  count(*) as spans,
  avg(duration) as avg_seconds
from records
where duration > 1
group by span_name
order by avg_seconds desc;
```

Your traces, metrics, and logs are queryable with real SQL, with no proprietary query language to learn.

## Common questions

**How do I add OpenTelemetry to a Rust application?** Run `cargo add logfire`, call `logfire::configure()...finish()?`, and hold the shutdown guard. The crate builds on `tracing` and OpenTelemetry, so existing `tracing` spans are exported automatically.

**Does this replace the `tracing` crate?** No. Logfire builds on `tracing` rather than replacing it. Your `#[tracing::instrument]` attributes and `tracing` macros keep working; Logfire gives them a backend, a UI, and SQL.

**Nothing is showing up.** With `SendToLogfire::IfTokenPresent`, a missing `LOGFIRE_TOKEN` disables sending silently. Check the token is set, and keep the `shutdown_guard()` binding alive — records flush on shutdown. Add `.with_console(Some(logfire::config::ConsoleOptions::default()))` to print records locally while you debug.

**Is Logfire locked to a proprietary format?** No. It is built on OpenTelemetry, the open industry standard. Your instrumentation is portable to any OTel-compatible backend.

Full details are in the [Rust setup guide](https://pydantic.dev/docs/logfire/instrument/rust/).

[Start free with Pydantic Logfire](https://logfire.pydantic.dev/)