Polymarket Acquires Dome Prediction API Startup

Polymarket has acquired prediction market API startup Dome for an undisclosed sum. The deal strengthens Polymarket’s developer infrastructure as competition intensifies across regulated and onchain event markets.

Dome, part of Y Combinator’s Fall 2025 cohort, provides a unified application programming interface that lets developers build tools across multiple prediction platforms, including Polymarket and Kalshi. The startup raised $500,000 from Y Combinator and a $4.7 million seed round, according to co-founder Kunal Roy’s public disclosures. Roy and co-founder Kurush Dubash were both founding engineers at Alchemy.

Is Infrastructure The Next Battleground For Prediction Markets?

Polymarket was last valued at $9 billion and is reportedly exploring fresh capital at a higher valuation. The acquisition marks only its second official deal, following the purchase of U.S.-licensed derivatives exchange QCEX, which enabled its reentry into the United States after a prior Commodity Futures Trading Commission (CFTC) action. By absorbing Dome’s cross-platform API, Polymarket may be positioning itself as infrastructure rather than only a venue.

Dome said on X that it plans to bring its focus on speed, reliability, and developer experience to the world’s largest prediction market. The ability to aggregate liquidity and data across venues could expand use cases beyond retail traders, particularly as institutions evaluate structured exposure to event-driven markets.

Polymarket has also signed distribution agreements with Major League Soccer, the National Hockey League, and media platforms including Substack. The next catalyst will be whether Polymarket pairs new capital with additional infrastructure acquisitions to consolidate liquidity and developer mindshare across global prediction markets.