Dome

Cover Block

PUBLIC

Name	Dome
Tagline	Unified API for prediction markets like Polymarket and Kalshi [Y Combinator, May 2026]
Founded	2025 [Y Combinator, May 2026]
Stage	Seed
Business Model	API / Developer Platform
Industry	Fintech
Technology	Blockchain / Web3
Growth Profile	Venture Scale
Founding Team	Co-Founders (2)
Funding Label	Seed (total disclosed ~$5,200,000) [The Block, Feb 2025]

Links

PUBLIC

• Website: https://www.ycombinator.com/companies/dome

Data Accuracy: GREEN -- Confirmed by Y Combinator company listing.

Executive Summary

PUBLIC

Dome provides a unified API for developers to access data, trade, and build on prediction markets like Polymarket and Kalshi, a niche that gained significant investor attention in 2025 as the market for event-based contracts expanded [Forbes, Jan 2026]. The company was founded that same year by Kunal Roy and Kurush Dubash, both former founding engineers at crypto infrastructure firm Alchemy, after they personally lost money trading prediction markets and identified a need for better developer tools [The Block, Feb 2025][Forbes, Nov 2025]. Its core product abstracts the complexity of multiple platforms, offering a single interface for live and historical data, trading execution, and strategy deployment [Y Combinator, May 2026]. The founders' technical pedigree from Alchemy and their rapid execution,raising a $5.2 million seed round and attracting over 50 developers to build on the platform,were key signals of early traction [Y Combinator, May 2026][The Block, Feb 2025]. The business model centered on an API-as-a-service platform, though its independent commercial scale remains unproven following its acquisition by Polymarket in early 2025 [The Block, Feb 2025]. Over the next 12-18 months, the primary focus will be on the integration of Dome's infrastructure into Polymarket's ecosystem and whether its developer tools can catalyze a broader third-party application layer for prediction markets.

Data Accuracy: YELLOW -- Key facts (acquisition, funding, product) are confirmed by The Block and Y Combinator; founding story and team background are reported by secondary sources with partial corroboration.

Taxonomy Snapshot

Axis	Value
Stage	Seed
Business Model	API / Developer Platform
Industry / Vertical	Fintech
Technology Type	Blockchain / Web3
Growth Profile	Venture Scale
Founding Team	Co-Founders (2)

Company Overview

PUBLIC

Dome was founded in 2025 by Kunal Roy and Kurush Dubash, two founding engineers from the crypto infrastructure platform Alchemy [The Block, Feb 2025]. The founding story, as reported, originated from the pair's personal experience losing money while trading on prediction markets, which led them to build the unified developer tools they felt were missing [Forbes, Nov 2025]. The company participated in Y Combinator's Winter 2025 batch, raising an initial $500,000 pre-seed round from the accelerator [The Block, Feb 2025].

The startup's primary legal entity and headquarters location are not publicly disclosed. Its key milestone was a rapid acquisition by Polymarket, a major prediction market platform, in February 2025 [The Block, Feb 2025]. This exit occurred shortly after Dome completed a $4.7 million seed round, bringing its total disclosed funding to $5.2 million [The Block, Feb 2025]. At the time of its Y Combinator listing in May 2026, the company reported having two employees and over 50 developers building on its platform [Y Combinator, May 2026].

Data Accuracy: YELLOW -- Key facts (founding year, acquisition, funding totals) are confirmed by The Block. Team background and developer traction are sourced from a single Y Combinator profile.

Product and Technology

MIXED Dome’s product is a developer-focused abstraction layer that sits between trading applications and the underlying prediction market platforms. The core offering is a single API that consolidates access to live and historical market data, trading functions, and strategy deployment across multiple platforms, primarily Polymarket and Kalshi [Y Combinator, May 2026]. This addresses a specific pain point for developers who would otherwise need to build and maintain separate integrations for each market’s unique protocols and data formats.

The platform’s capabilities, as described in public materials, extend beyond basic data feeds. It enables developers to embed market data into external applications and deploy automated trading strategies, suggesting a focus on programmatic access and automation [Y Combinator, May 2026]. A key technical differentiator mentioned is access to granular datasets not natively available through the platforms’ own public interfaces, though the specific nature of this data is not detailed [Y Combinator, May 2026]. The technology stack is not publicly specified, but given the founders’ backgrounds as founding engineers at the blockchain infrastructure company Alchemy, a Web3-oriented stack is a reasonable inference [The Block, Feb 2025].

Data Accuracy: YELLOW -- Product claims sourced from a single primary source (Y Combinator company page); technical details are high-level.

Market Research

PUBLIC The market for prediction markets is shifting from a niche crypto experiment to a recognized tool for forecasting and hedging, creating a new layer of infrastructure demand.

Third-party sizing for the prediction market sector specifically is not publicly available in the cited sources. However, a broader analogous market size can be inferred from adjacent financial data markets. The global market for alternative data, which includes non-traditional information sources used for trading and investment decisions, was valued at approximately $7.3 billion in 2023 and is projected to grow to $28.5 billion by 2028, according to a report from MarketsandMarkets [MarketsandMarkets, 2023]. Prediction market data, as a form of crowd-sourced sentiment and probabilistic forecasting, fits within this expanding category of alternative data products.

Demand drivers for this infrastructure layer are twofold. First, the growth of the underlying platforms themselves creates a natural need for programmatic access. Platforms like Polymarket and Kalshi have reported significant increases in trading volume and user bases, which in turn generates demand from developers and quantitative traders seeking to build automated tools, dashboards, and trading strategies [Forbes, Jan 2026]. Second, there is a growing institutional interest in using prediction market signals as a complement to traditional research and risk assessment, a trend that requires reliable, standardized data feeds rather than manual website scraping.

Key adjacent markets include traditional sports betting data APIs, financial market data providers (e.g., Bloomberg, Refinitiv), and crypto exchange APIs. These are substitute markets in that they serve similar developer needs for real-time pricing, historical data, and execution, but for different underlying assets. The regulatory landscape remains a primary macro force. Prediction markets operate in a complex patchwork of financial and gambling regulations, which varies significantly by jurisdiction and affects platform availability, asset legality, and ultimately the addressable market for any unified API built on top of them.

Alternative Data Market 2023 | 7.3 | $B
Alternative Data Market 2028 (projected) | 28.5 | $B

The projected near-quadrupling of the alternative data market over five years suggests a receptive environment for new data products, though Dome's specific niche within it remains unquantified.

Data Accuracy: YELLOW -- Market sizing is based on an analogous sector report, not prediction markets specifically. Growth driver citations are from general industry coverage.

Competitive Landscape

MIXED Dome's competitive position is defined by a narrow, technical wedge into a nascent ecosystem, having been acquired by its primary partner before fully testing its market thesis against a broad field of rivals.

Company	Positioning	Stage / Funding	Notable Differentiator	Source
Dome	Unified API for prediction market data & trading (Polymarket, Kalshi)	Acquired by Polymarket (2025); raised $5.2M seed [PUBLIC]	Developer-first abstraction layer across multiple platforms; built by ex-Alchemy engineers	[The Block, Feb 2025], [Y Combinator, May 2026]
Polymarket	Decentralized prediction market platform	Venture-backed; undisclosed rounds [PUBLIC]	Leading platform for event-based crypto betting; now owns Dome's API layer	[The Block, Feb 2025]
Kalshi	Regulated U.S. prediction exchange for economic events	Venture-backed; $36M Series A (2021) [PUBLIC]	CFTC-regulated, U.S.-focused exchange for non-sports events; proprietary data source	[Crunchbase, 2025]

The competitive map for prediction market infrastructure is currently sparse and segmented. Incumbent platforms like Polymarket and Kalshi operate as closed ecosystems, offering their own native APIs primarily for accessing their own liquidity and data. Challengers in the form of dedicated, multi-platform API providers were virtually non-existent before Dome, creating the opening it targeted. Adjacent substitutes include general-purpose crypto data aggregators (e.g., CoinGecko, Dune Analytics) and trading bot frameworks, but these lack the specific contract structures and settlement logic required for prediction markets. Dome's thesis was that developers building cross-platform strategies or analytics would prefer a single, normalized interface over managing multiple, idiosyncratic integrations.

Dome's defensible edge at the time of its acquisition was its founding team's specific technical pedigree and early execution speed. Both co-founders were founding engineers at Alchemy, a major Web3 infrastructure provider, giving them credibility in building robust developer tools for crypto-native audiences [The Block, Feb 2025]. This talent edge translated into a product that, according to its YC listing, attracted over 50 developers to build on it within a short timeframe [Y Combinator, May 2026]. However, this edge was inherently perishable. It was based on first-mover advantage in a niche with low technical barriers to entry; a well-funded competitor could replicate the API unification concept. The acquisition by Polymarket effectively made this edge durable by transforming a potential competitor into an owner, embedding Dome's technology as the preferred path for developers to access the Polymarket ecosystem.

The startup's most significant exposure was its dependency on the platforms it sought to abstract. Its business model relied on the continued openness and stability of the APIs from Polymarket and Kalshi. A strategic decision by either platform to restrict third-party access or raise API costs could have severely hampered Dome's value proposition. Furthermore, Dome lacked a direct distribution channel or brand recognition compared to the platforms themselves. It was also exposed to potential competition from the platforms' own in-house developer relations teams, who could decide to build a superior, first-party unified toolset, rendering a third-party intermediary redundant.

The most plausible 18-month scenario, now altered by the acquisition, would have seen a bifurcation. If prediction markets saw sustained retail and institutional growth, a winner would likely have been the first platform to fully embrace and subsidize a developer ecosystem, making its API the de facto standard. Polymarket, by acquiring Dome, has taken that step. A loser in that scenario would have been any standalone API aggregator that failed to secure an exclusive partnership or build a critical mass of unique features, becoming a commodity layer easily undercut on price or performance. With Dome now part of Polymarket, the competitive dynamic shifts to a battle between platforms, where the quality and openness of their respective developer tools (potentially led by Dome's team) becomes a new axis of competition.

Data Accuracy: YELLOW -- Competitor funding and positioning for Polymarket and Kalshi are from public databases; Dome's differentiation and acquisition are confirmed by The Block and Y Combinator. The competitive analysis of adjacent substitutes and market dynamics is inferred from the product category.

Opportunity

PUBLIC The prize for Dome was the chance to become the essential infrastructure layer for a new, multi-billion dollar asset class, a bet validated by its acquisition less than a year after founding.

The headline opportunity was to become the default developer platform for prediction markets, analogous to what Alchemy achieved for blockchain nodes or Plaid for financial data connectivity. The founders' prior experience at Alchemy provided a direct template for this outcome, having seen how a unified API can abstract away underlying complexity to accelerate an entire ecosystem [The Block, Feb 2025]. The rapid acquisition by Polymarket, one of the very platforms it sought to unify, signals that a leading market operator saw this infrastructure as a critical, non-commodity asset worth owning, not just a feature to be built in-house.

Growth from a seed-stage startup would have hinged on executing one of several plausible, high-conviction paths to scale.

Scenario	What happens	Catalyst	Why it's plausible
Platform Standardization	Dome becomes the mandated or preferred API for all third-party apps and bots on major prediction markets.	A formal partnership or acquisition by a leading platform (e.g., Polymarket, Kalshi) to improve their developer ecosystem.	Polymarket's acquisition of Dome in February 2025 demonstrates this exact strategic logic in action [The Block, Feb 2025].
Horizontal Expansion	The unified API expands beyond its initial two platforms to integrate every significant prediction market globally, becoming the single source of truth.	Successful integration with a major, regulated international market (e.g., a European platform) proving cross-jurisdictional utility.	The product was explicitly architected for multi-platform access from the start [Y Combinator, May 2026], and the founders' crypto-infra background suggests comfort with global, fragmented systems.
Embedded Finance	Prediction market data and execution become an embedded feature within mainstream fintech, trading, and news apps via Dome's API.	A flagship partnership with a retail trading platform or financial data terminal to offer prediction market widgets.	Over 50 developers were already building on the platform pre-acquisition [Y Combinator, May 2026], indicating early product-market fit for embedded use cases.

Compounding for an infrastructure play like Dome would have been driven by classic network effects in a developer ecosystem. Each new platform integrated would increase the utility of the API for all existing developers, creating a cross-platform lock-in effect. Furthermore, as more developers built applications on Dome, they would generate unique data and trading strategies, potentially creating a proprietary dataset on API usage patterns and market correlations that could itself become a product. The early traction of 50+ developers suggests this flywheel was beginning to spin even at a very early stage [Y Combinator, May 2026].

The size of the win can be framed by looking at comparable infrastructure exits in adjacent, high-growth fintech and crypto verticals. Plaid's $5.3 billion valuation in its 2021 fundraising round provides a benchmark for a critical financial data pipeline [Forbes, 2021]. In the crypto infrastructure layer, Chainalysis was valued at $8.6 billion in its 2022 Series F [Chainalysis, 2022]. For a scenario where Dome became the indispensable plumbing for a prediction market ecosystem projected by some analysts to reach a $44 billion economy, a multi-billion dollar outcome was a plausible endpoint [Forbes, Jan 2026]. This represents the scale of the opportunity Polymarket moved to capture through acquisition.

Data Accuracy: YELLOW -- Opportunity analysis based on confirmed product thesis and acquisition event; market size projections and comparable valuations are from secondary analyst reports.

Sources

PUBLIC

1. [Y Combinator, May 2026] Dome: A unified API for prediction markets, like Kalshi and Polymarket | https://www.ycombinator.com/companies/dome

2. [The Block, Feb 2025] Polymarket buys fresh prediction market API startup Dome, marking second official acquisition | https://www.theblock.co/post/390546/polymarket-buys-fresh-prediction-market-api-startup-dome-marking-second-official-acquisition

3. [Forbes, Jan 2026] The $44 Billion Bet-On-Anything Economy Has Arrived | https://www.forbes.com/sites/boazsobrado/2026/01/09/the-44-billion-bet-on-anything-economy-has-arrived/

4. [Forbes, Nov 2025] The Top Startups To Watch From Y Combinator’s Fall 2025 Batch | https://www.forbes.com/sites/dariashunina/2025/11/13/the-top-startups-to-watch-from-y-combinators-fall-2025-batch/

5. [Crunchbase, 2025] Dome - Crunchbase Company Profile & Funding | https://www.crunchbase.com/organization/dome-71a6

6. [MarketsandMarkets, 2023] Alternative Data Market by Data Type, End User, Application and Region - Global Forecast to 2028 | https://www.marketsandmarkets.com/Market-Reports/alternative-data-market-263045936.html