South Korean super-app Toss has partnered with Optimism and Sunnyside Labs on a three-month proof-of-concept testing whether won-linked stablecoins can run on public blockchain infrastructure while meeting South Korea’s financial regulations, the companies announced July 8.
The project, announced on July 8, will assess whether blockchain technology can support institutional payment systems while complying with local financial regulations.
The won-linked stablecoins initiative will focus on payment settlement, regulatory compliance, and transaction privacy, with the partners seeking to determine whether public blockchain infrastructure can satisfy the standards required by financial institutions.
Toss begins three-month won-linked stablecoins infrastructure trial
According to a press release shared with crypto.news, Toss will collaborate with Ethereum Layer-2 network Optimism and blockchain privacy developer Sunnyside Labs to examine the feasibility of deploying won-linked stablecoins on public blockchain infrastructure.
The proof-of-concept will run for three months and is designed to determine whether blockchain networks can support institutional-grade financial services while maintaining compliance with South Korea’s regulatory framework.
The companies will focus on three primary areas during the evaluation:
- Direct management of payment and settlement by financial institutions.
- Compliance with customer identification (KYC) and anti-money laundering (AML) regulations.
- Protection of sensitive financial and transaction information on a public blockchain.
According to the announcement, Optimism will provide the blockchain infrastructure through its OP Stack technology, while Sunnyside Labs will integrate its Privacy Boost solution to strengthen confidentiality without compromising regulatory oversight.
A Toss official explained the project’s objective, saying:
“The project is intended to verify infrastructure that combines Ethereum’s security with a dedicated network built for local currency-based financial services while allowing interoperability with other blockchain ecosystems.” — Toss official
The outcome could influence how won-linked stablecoins are implemented in South Korea’s broader digital payments landscape if the infrastructure proves capable of supporting regulated financial services.
Privacy and compliance remain central to won-linked stablecoins project
One of the biggest technical hurdles facing public blockchain adoption is balancing transparency with privacy. Public blockchain networks typically expose wallet balances and transaction histories to network participants, creating challenges for financial institutions handling sensitive customer data.
To address this issue, Sunnyside Labs will deploy its Privacy Boost technology throughout the trial.
According to the companies, the solution allows confidential financial information to remain private while still enabling regulated institutions to verify transactions and satisfy existing compliance obligations.
The partners will also evaluate whether the infrastructure can process high transaction volumes efficiently, a key requirement for large-scale payment networks.
Toss currently serves approximately 30 million users and supports more than 500,000 online and offline merchants, giving the company a substantial platform for future blockchain-based payment experiments should the trial prove successful.
The initiative reflects growing interest in won-linked stablecoins as South Korean financial technology firms explore blockchain infrastructure capable of supporting secure, compliant digital payments without sacrificing scalability.
OP Stack chosen to power blockchain testing
At the heart of the trial is Optimism’s OP Stack, a modular blockchain framework designed to allow organizations to build application-specific blockchain networks while leveraging Ethereum for security and transaction settlement.
Unlike Ethereum’s main network, Layer-2 solutions process transactions separately before finalizing them on Ethereum, helping lower transaction costs while improving throughput.
Through the pilot, Toss will assess whether OP Stack can support a dedicated blockchain network optimized specifically for Korean digital payment services rather than relying entirely on shared public infrastructure.
Optimism’s technology has already been adopted by more than 30 blockchain networks, including projects developed by Sony, World Chain, Uniswap, OKX Layer, and Kraken. The company also provides institutional deployments intended to satisfy regulatory and security requirements, with regulated financial firms such as Europe’s Bitpanda already using the technology.
The evaluation could provide valuable insights into whether won-linked stablecoins can operate on blockchain infrastructure built specifically for regulated financial institutions while maintaining interoperability with other blockchain ecosystems.
Trial builds on Optimism’s recent infrastructure research
The collaboration follows another recent infrastructure initiative by Optimism aimed at improving blockchain performance.
Weeks before announcing the Toss partnership, Optimism completed a four-week experiment on its OP Mainnet testing stake-based transaction ordering alongside its existing gas-fee mechanism.
According to the company, the pilot examined whether staking incentives could improve transaction prioritization without changing the user experience for regular network participants.
The latest partnership with Toss extends that broader effort by focusing on institutional payment infrastructure and evaluating whether won-linked stablecoins can deliver secure, scalable, and regulation-compliant financial services on public blockchain technology.
If successful, the verification program could provide a technical foundation for future blockchain-powered payment systems in South Korea, where financial institutions continue exploring regulated digital asset infrastructure while maintaining strict compliance and consumer protection standards.
Primary source: Toss press release (shared with crypto.news).