Spark and Uniswap have launched a shared liquidity system called the FX Layer to streamline stablecoin swaps between major dollar-pegged tokens. The initiative aims to eliminate the need for each stablecoin issuer to build separate liquidity infrastructure, instead offering a common pool where banks, fintechs, and payment companies can connect.
As the first phase, Spark is migrating approximately $150 million from its USDS ecosystem into Uniswap v4, establishing initial liquidity for swap pools supporting USDS, Tether's USDT, and PayPal USD (PYUSD). This deployment is described as one of the largest automated market maker liquidity migrations in decentralized finance.
The collaboration combines Spark’s liquidity management framework with Uniswap v4’s programmable AMM architecture. Spark acts as the coordination layer that allocates and manages liquidity, while Uniswap provides the decentralized exchange infrastructure. A key component is the DualPool hook — a programmable mechanism that directs idle capital toward approved yield strategies when not needed for trade execution, improving capital efficiency.
Spark CEO Sam MacPherson framed the move as a shift in stablecoin competition. “The next generation of stablecoins won’t be defined by who can issue another digital dollar. It will be defined by the infrastructure that allows hundreds of issuers to operate together at global scale,” he said. “The native stablecoin remains visible. The liquidity infrastructure becomes invisible. That’s the future we’re building.”
The launch arrives as institutional interest in branded stablecoins accelerates following the GENIUS Act and as firms like PayPal, Ripple, Robinhood, and Revolut expand their digital dollar offerings. Stablecoins processed over $28 trillion in adjusted volume in 2025 (133% CAGR since 2023), and projections see annual payment flows reaching $56.6 trillion by 2030. The FX Layer addresses the core problem of liquidity fragmentation: traditionally, every new issuer must bootstrap its own market makers and pools, leading to inefficient capital use.
Uniswap founder Hayden Adams noted that Uniswap pools already power roughly 60% of stable-to-stable trading volume, and the DualPool hook further optimizes returns. The initial deployment is live on Ethereum, and future upgrades will introduce a Shared Liquidity Layer alongside the DualPool hook. Spark said additional integrations are in development across the stablecoin ecosystem, with the DualPool framework undergoing separate security reviews.
If successful, the model could establish shared infrastructure where multiple issuers compete on products and customer relationships while relying on a common liquidity backbone — potentially making onchain stablecoin markets more scalable as institutional participation grows.
