Liquidity Provision / Market Making on Polymarket

How It Works The mohamedkhaled105656/polymarket-terminal CLI includes liquidity provision as a core feature, and the broader PMXT unified API (pmxt-dev/pmxt) enables programmatic order placement across Polymarket and Kalshi. Market making involves posting resting limit orders at both the bid and ask of a prediction market, profiting from the spread when both sides fill. The market maker must continuously update quotes as the fair value of the market changes.

Entry / Exit Conditions Entry: post a YES limit order below fair value and a NO limit order below fair value (equivalently, a YES ask above fair value) simultaneously. The spread between the two represents gross profit per round-trip. Quotes are updated (or cancelled and reposted) whenever the underlying event probability changes materially — e.g., on news events, price moves in reference assets, or time decay as the market approaches resolution.

Verified Results No specific P&L data is presented. Market making on prediction markets is a known viable strategy employed by professional firms; the viability depends heavily on the specific market's liquidity and the maker's ability to accurately estimate fair value.

Implementation Notes PMXT (1915 stars, 225 forks — the highest-quality repo in this report) provides a unified API that abstracts order placement mechanics across platforms, significantly lowering implementation complexity. Effective market making requires a real-time fair value model (e.g., for crypto price markets, a model tied to the underlying asset price; for political markets, a news-aware NLP model). Inventory management is critical — large one-sided fills leave the market maker with directional exposure.

Risks - **Adverse selection**: informed traders will selectively hit the market maker's stale quotes, causing losses on the "wrong" side. - **Inventory risk**: a sudden resolution-relevant event can render one side of the book nearly worthless before the maker can cancel. - **Low spread markets**: highly liquid Polymarket markets have very tight spreads, limiting per-trade profitability. - **Platform fees**: Polymarket charges maker/taker fees that must be accounted for in spread calculations.