Toss, the fintech super-app with more than 15 million users in South Korea, has signed a memorandum of understanding with Optimism and Sunnyside Labs to run a proof of concept on a Korean won-pegged stablecoin. The three-month PoC will test whether Optimism’s layer-2 infrastructure can support compliant digital currency payments in one of Asia’s most tightly regulated financial markets.
What the partnership actually involves
The MOU, signed on July 8, pairs three organizations with very different skill sets. Toss brings the user base and financial services muscle. Optimism contributes its OP Stack, the modular framework that powers its Ethereum layer-2 network. Sunnyside Labs rounds out the trio with privacy-focused solutions, a critical piece of infrastructure when you’re dealing with regulated payments in a country that takes KYC and AML seriously.
Kyu-ha Kim, Toss’s Chief Business Officer, emphasized the importance of the collaboration in understanding the feasibility of a KRW-pegged stablecoin. The PoC will specifically assess whether the OP Stack can handle the throughput, compliance, and cost requirements that a payment-grade stablecoin demands.
Back in March 2026, the company announced plans to issue a won-backed stablecoin. Then in June, Toss Bank signed a separate MOU with the Solana Foundation to test stablecoin-based remittance and settlement. The Optimism track focuses on layer-2 Ethereum infrastructure. The Solana track focuses on remittance use cases.
