limenpay 0.1.0a2

x402 paywall for AI agent traffic. Python SDK + proxy for FastAPI, Flask, Django, Starlette.

limen (Python)

x402 paywall middleware + standalone proxy for Python. USDC on Base and Solana. Drop-in for FastAPI, Flask, Django, Starlette.

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Install

pip install limen
# With optional framework extras:
pip install "limen[fastapi]"
pip install "limen[django]"
pip install "limen[flask]"

Python 3.11+.

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FastAPI quickstart

import os
from fastapi import FastAPI
from limen.fastapi import LimenMiddleware

app = FastAPI()
app.add_middleware(
    LimenMiddleware,
    wallets={"base": os.environ["LIMEN_WALLET_BASE"]},
    endpoints=[
        {"path": "/api/v1/weather/*", "price_usdc": "0.001"},
        {"path": "/api/v1/premium/**", "price_usdc": "0.05"},
    ],
    redis_url=os.environ["REDIS_URL"],
)


@app.get("/api/v1/weather/{city}")
def weather(city: str) -> dict:
    return {"city": city, "temp_c": 17}

Flask

from flask import Flask
from limen.flask import limen_middleware

app = Flask(__name__)
app.wsgi_app = limen_middleware(
    app.wsgi_app,
    wallets={"base": os.environ["LIMEN_WALLET_BASE"]},
    endpoints=[{"path": "/api/v1/*", "price_usdc": "0.001"}],
    redis_url=os.environ["REDIS_URL"],
)

Django

settings.py:

MIDDLEWARE = [
    "limen.django.LimenMiddleware",
    # ...
]

LIMEN = {
    "wallets": {"base": os.environ["LIMEN_WALLET_BASE"]},
    "endpoints": [{"path": "/api/v1/*", "price_usdc": "0.001"}],
    "redis_url": os.environ["REDIS_URL"],
}

Standalone proxy

limen start --config limen.config.yml --upstream http://localhost:3000

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CLI

limen start        Run the proxy.
limen doctor       Check config + connectivity + ports.
limen verify       Verify a transaction against config.
limen config       lint | print | explain | migrate
limen keys         generate-webhook-secret | generate-admin-keypair
limen audit        verify | tail

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Security

This package enforces the nine invariants listed in docs/security.md § 4. Report vulnerabilities privately — see SECURITY.md.

Full getting-started, API reference, scaling, compliance docs: ../../docs/.

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Development

hatch env create
hatch run test     # pytest with coverage
hatch run lint     # ruff
hatch run typecheck  # mypy strict

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License

MIT — see LICENSE.