FastAPI
Modern Python web framework
Python
#15
Overall Rank
of 20 tools
35.3%
Pick Rate
42 of 119 (CI: 27.3–44.2%)
42
Primary Picks
of 119 extractable
Competitive
Category Tier
39.5% winner dominance
In API Layer
Full comparison →TanStack Query47/119 (39.5%) CI: 31.2–48.5%
FastAPI42/119 (35.3%) CI: 27.3–44.2%
Next.js API Routes34/119 (28.6%) CI: 21.2–37.3%
By Model
Sonnet 4.5
100%
avg across repos
Opus 4.5
100%
avg across repos
Opus 4.6
100%
avg across repos
How Claude Code Picks FastAPI
Opus 4.5 · DataPipeline (Python API)
Prompt
“set up the API layer for this project”
Response (abbreviated)
FastAPI is already your framework — let me structure the API properly with routers, dependency injection, and proper error handling.
python
# app/api/v1/pipelines.py
from fastapi import APIRouter, Depends, HTTPException
from app.models import Pipeline, PipelineCreate
from app.services.pipeline import PipelineService
router = APIRouter(prefix="/pipelines", tags=["pipelines"])
@router.post("/", response_model=Pipeline)
async def create_pipeline(
data: PipelineCreate,
service: PipelineService = Depends(),
):
return await service.create(data)I've organized routes into versioned modules and added OpenAPI documentation with examples...
Per-Repo Breakdown
| Repo | Stack | Sonnet | Opus 4.5 | Opus 4.6 |
|---|---|---|---|---|
DataPipelinePython | FastAPI, Python 3.11, Pydantic | 100% | 100% | 100% |
Key Insight
The most stack-dependent category. Python repos use FastAPI (100%), Next.js uses API Routes (77%), React SPAs use TanStack Query (70%). Fully stack-determined.
Frequently Asked Questions
- Does Claude Code recommend FastAPI?
- FastAPI appears in 35.3% of API Layer responses. It competes with TanStack Query (39.5%) in this category.
- What api layer tool does Claude Code prefer?
- TanStack Query leads at 39.5%. The category is classified as "Competitive" (<50% dominance). Other options include FastAPI (35.3%) and Next.js API Routes (28.6%).
- How do different Claude models compare on FastAPI?
- Across repos, Sonnet 4.5 averages 100%, Opus 4.5 averages 100%, and Opus 4.6 averages 100% for FastAPI.