A Unified SDK for Prediction Markets

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predmarket is an asyncio-native Python-based library that communicates directly with prediction markets (Kalshi and Polymarket).

Both Kalshi and Polymarket provide public-facing APIs with high rate limits. predmarket aims to unify these two APIs into one install, one format, and one library to learn. The goal to be abstract enough to be intuitive, but not lose any power of the individual APIs.

Currently, Websocket support is under development. A working implementation of Polymarket's CLOB WS API is available, while Kalshi's is still being developed.

Install

uv add predmarket or pip install predmarket

Basic Usage

REST

from predmarket import KalshiRest, PolymarketRest
from httpx import AsyncClient

async def main()
    async with AsyncClient() as client:

        # Initialize fetchers. Each with exact same public-facing API.
        kalshi = KalshiRest(client)
        polymarket = PolymarketRest(client)

        # Fetch available Questions (e.g. "When will Elon Musk get to Mars?", known as events in native API)
        kalshi_questions = await kalshi.fetch_questions()
        polymarket_questions = await polymarket.fetch_questions(limit=10, asc=True) # Polymarket-specific query params

        # Fetch available Contracts  (e.g. "Will Elon Musk get to Mars before 2026?", these are individual "solutions" for a given question , Markets in native APIs)
        kalshi_contracts = await kalshi.fetch_contracts()
        polymarket_contracts = await polymarket.fetch_contracts() # Polymarket-specific query params

WS

from predmarket import PolymarktWS # Kalshi is NOT currently supported, but will be very solutions

async def main():
    async with PolymarketWS.connect() as socket:
        polymarket = PolymarketWS(socket)
        for row in polymarket.stream(["AB.....XYZ"]): # Example of fetching real markets later in docs
            print(row) # Row is a pydantic model. Autocomplete!

More Information

predmarket is under rapid development. Expect breaking changes unless indiciated otherwise.