Codex: Unlocking the Trillion-Dollar Onchain FX Opportunity – Interview with Co-Founder and CEO Haonan Li

New stablecoin race: As stablecoins become one of the fastest-growing assets in global finance, a new contest is emerging, not over who issues them, but where they live. Leading firms like Stripe, Circle, and Tether are now building dedicated blockchains designed specifically for stablecoin activity, with Stripe’s incubated network Tempo recently raising $500 million at a $5 billion valuation to accelerate its launch.

• Why it matters: The move toward specialization reflects a broader realization: general-purpose blockchains such as Ethereum and Tron were never designed for payments. Their variable fees, congestion, and open ledgers make them poorly suited for stablecoin settlement at scale. The next generation of stablecoin-native networks aims to fix this — offering instant finality, predictable costs, and selective privacy, the features required for real-world use cases like remittances, payroll, and corporate finance.

Codex as first mover: Among them, Codex, a stablecoin Layer-2 backed by Dragonfly Capital, Coinbase, and Circle Ventures, has emerged as one of the earliest to gain real traction. The Layer-2 surpassed $3 billion in cumulative flows last week, positioning itself as the earliest stablecoin network to combine institutional needs with onchain speed.

Interview: To understand Codex’ positioning and the broader implications of building blockchain infrastructure purpose-built for stablecoins and onchain foreign exchange, we spoke with Haonan Li, co-founder and CEO of Codex.

On Codex’ strategic positioning and differentiation:

“We’re the only stablecoin Layer-2 built on top of Ethereum, which gives us three strategic advantages.

First, speed to market. Tapping into Ethereum’s ecosystem lets us focus entirely on our vertical. It allows us to move faster, refine our product more quickly, and reach market sooner than general-purpose chains that must first solve the broader complexities of operating as standalone Layer-1s.

Second, security and neutrality. Ethereum is the most decentralized and proven settlement layer. At the same time, fintechs and issuers don’t want to build on chains controlled by competitors. Codex is designed to be a neutral settlement layer where everyone — banks, PSPs, and issuers — can operate without conflicts of interest.

Third, liquidity. Currently, about 54% of all stablecoin supply is held on Ethereum Mainnet, and the network processes roughly 30% to 40% of total monthly stablecoin transaction volume. That matters because liquidity is the decisive property that allows stablecoin infrastructure to work at scale.

The network that makes it cheapest and easiest to move between fiat and stablecoins will always come out ahead, while factors such as speed, privacy, or gas optimization remain secondary.”

On what is hard about bringing global FX onchain:

“The challenge with onchain FX is that it’s made up of three core pillars that need to function seamlessly, and each one still requires improvement.

1) On/off-ramps: Most stablecoin <> fiat bridges remain expensive and slow. Without compliant, high-throughput ramps, institutions can’t move real volume at reasonable cost.

2) Liquidity and trading venues: USD stablecoin pairs already trade efficiently onchain, but cross-currency pairs like USDC–EURC do not. To change that, trading infrastructure needs further refinement and liquidity must improve.

3) Abstraction layers: At the application layer, payment flows should abstract away FX complexity. For example, middleware should automatically execute onchain FX conversions at the point of payment to reduce friction.

The biggest bottleneck, however, remains liquidity, especially for long-tail non-USD stablecoins. Unlocking that is essential to bring the trillion-dollar FX market fully onchain.

Most chains stay away from the fiat boundary, but that’s exactly where most of the friction lies. That’s why we see it as essential to build better infrastructure around it. When off-the-shelf solutions fall short, we develop the missing pieces ourselves, and that’s becoming a larger part of our work as the network grows.”

On Codex' go-to-market strategy:

“Today we operate as a wholesale supplier of stablecoin liquidity. Exchanges, payment service providers, and fintechs source liquidity from us to power their user-facing products.

Right now, most of that wholesale activity takes place on Codex. Some downstream flows still move across other chains, which is fine. Our strategy is to begin with high-volume institutional corridors and expand downstream over time.

A good example is our recent partnership with PDAX, a leading digital asset exchange in the Philippines. The US-Philippines corridor is among the largest cross-border payment routes worldwide, processing around 3$ billion in remittances each month. Our stablecoin liquidity supports PDAX’s remittance operations and helps people send money home faster and at lower cost.

In the next six months, we’ll bring FX fully onchain. When that launches, it will mark the biggest step change for stablecoins since Tether. At that point, stablecoins won’t just serve as payment assets, they’ll become the settlement infrastructure for global currency conversion.”

On how the stablecoin infrastructure market will look in the future:

“The market is clearly shifting toward specialization rather than generalization. Every stablecoin chain that’s launched this year is taking a distinct approach, each focused on its own niche. Some have followed the familiar playbook of using heavy token incentives to attract liquidity, but history shows that liquidity only sticks when there’s a real use case behind it.

That's why, over time, we’ll see each network focus on one vertical such as trading, payments, or FX, and connect through shared settlement layers. Stablecoins will serve as the common language between them, the universal unit of settlement across networks. Codex’ role is to ensure stablecoins remain deeply liquid and easily transferable across specialized networks, creating a unified layer for global settlement.”