Optimism says Toss is the fourth regulated financial institution in a year to pick the OP Stack, after Bitpanda, Kraken and Mitsui.
Toss, the South Korean fintech app with roughly 30 million registered users, is testing a Korean won stablecoin on Optimism’s OP Stack, Optimism said on X Wednesday. The proof of concept also involves Sunnyside Labs, whose “Privacy Boost” tool is meant to shield transaction data on a public blockchain while preserving compliance access.
Optimism, the company behind the OP Stack framework used to build layer-2 networks, called the tie-up the fourth time in a year a regulated financial institution has adopted the OP Stack in a new market, following Bitpanda’s Vision Chain in Europe, Kraken’s Ink in the US and Mitsui’s Zipangcoin in Japan.
Kyle Jenke, chief business officer at OP Labs, said the pilot is “about demonstrating that the OP Stack can meet the compliance, privacy, and performance standards that regulated financial institutions require.” Toss chief business officer Q-Ha Steve Kim said the company aims “to build a highly trusted, compliant digital financial infrastructure tailored to the Korean market,” using the same post.
Three-Month Test
The arrangement runs as a three-month proof of concept, according to a post from crypto researcher Jay Chan, covering whether a financial institution can manage settlement, meet KYC and anti-money-laundering requirements, and protect transaction privacy on a public chain at the same time. Toss operates over 500,000 online and offline payment networks, per a summary of Kim’s comments on the deal.
Optimism’s post frames the collaboration as a test rather than a commitment to launch a stablecoin.
The OP Stack already underpins Sony’s Soneium, Uniswap’s Unichain and OKX’s X Layer, among others, giving Toss an established multi-chain ecosystem to plug into rather than building isolated infrastructure. Whether the pilot converts into a live KRW stablecoin will depend on regulatory sign-off in South Korea, which has not yet finalized its stablecoin licensing framework.
