Layer gives developers one interface to find markets, stream normalized data, place orders, and track positions across Kalshi and Polymarket. Build your trading system once instead of rebuilding venue plumbing.
For teams building trading bots, trading apps and AI agents. You own the strategy and the screen. Layer runs the venue plumbing.
Kalshi and Polymarket word the same bet differently, and sometimes settle it differently. Layer reads both venues’ settlement rules, flags where they differ, and checks every match again once it settles.
Prices, spreads and depth for matched markets, ready for your strategy, app or agent.
A quoted price isn’t your price. Layer breaks down fees, spreads, and estimated slippage per trade, so your strategy prices reality instead of the quote.
Same call to place or cancel an order on Kalshi or Polymarket. Change the venue, keep the code.
Let a strategy or AI agent trade without giving it a blank check.
After an order is sent: what filled, what you hold, and where your money is, in one shape across venues.
Recorded order books and a fill simulator, as an API. Plug them into your own backtester, or run one strategy in backtest, paper and live with the SDK.
Matching, prices, execution, and fills for Kalshi and Polymarket, without rebuilding the plumbing.