Python Framework

FastAPI Monitoring with TraceKit

FastAPI is built for speed -- but async dependency injection chains are invisible by default, Pydantic serialization costs hide in every response, and BackgroundTasks lose trace context entirely. TraceKit makes every async hop visible.

FastAPI observability challenges

Common problems that FastAPI developers face in production -- and how TraceKit solves them.

Async Dependency Injection Tracing

FastAPI's Depends() system is powerful but opaque. A single endpoint can trigger a tree of async dependencies -- auth, database sessions, feature flags -- and you cannot see which dependency is slow or failing. TraceKit traces every Depends() resolution so the full injection chain appears in your trace.

Pydantic Validation Overhead

Every FastAPI request and response passes through Pydantic serialization. With nested models and large payloads, validation and serialization can consume significant time that is invisible in standard profiling. TraceKit measures Pydantic processing time per endpoint so you can spot serialization bottlenecks.

Background Task Context Loss

FastAPI's BackgroundTasks run after the response is sent, but they lose the original request's trace context. A task that writes to a database or calls an external API appears as an orphan trace. TraceKit propagates context into background tasks so they stay connected to the originating request.

Get started in minutes

Add OpenTelemetry instrumentation to your FastAPI app with a few lines of code.

from opentelemetry.instrumentation.fastapi import FastAPIInstrumentor
from fastapi import FastAPI

app = FastAPI()
FastAPIInstrumentor.instrument_app(app)

@app.get("/items/{item_id}")
async def read_item(item_id: int):
    return {"item_id": item_id}

See the full Python integration guide

Python Distributed Tracing Guide

Go deeper with our Python distributed tracing guide -- covering common pain points, production patterns, and code examples.

What you get with TraceKit

Distributed Tracing

Trace requests across FastAPI endpoints, async dependencies, Pydantic validation, and background tasks. See the full async request lifecycle from ingress to response.

Live Code Monitoring

Set breakpoints in your FastAPI route handlers and dependency functions. Inspect Pydantic models, request state, and async context in production without redeploying.

Simple Pricing

$29/month flat for your entire FastAPI application. No per-worker fees for Uvicorn, no per-request charges -- one price for full async observability.

Ready to add observability to FastAPI?

Get started with TraceKit in under 5 minutes. $29/month flat -- no per-host fees, no surprises.