Solid users can now earn euro yield directly in the app, by depositing EURC. The new option, called soEUR, is powered by Byzantine's infrastructure and targets up to 6% APY, depending on market conditions. It is available to Solid cardholders in the EU and EEA, the United Kingdom and Switzerland, and users keep control of their funds onchain.

It follows Solid's euro cards launch earlier this month: European users can now save, earn and spend in euros from one app.

Why euro yield matters

Most onchain yield is denominated in dollars. For users who hold and spend in euros, accessing it usually means converting to a dollar stablecoin themselves, which adds currency exposure: a move in the euro-dollar rate can reduce or outweigh the interest earned.

Solid's euro yield keeps things in euros. Users deposit EURC, and the strategy behind it is designed to hedge the euro-dollar exposure, so their position stays denominated in euros.

What Solid users get

• Euro yield in the app they already use. Users deposit EURC from the Solid app, with no conversion on their side and no separate application.
• Returns from digital credit. Returns come from interest paid by borrowers on Morpho and Aave, with the euro-dollar exposure hedged. The rate varies with borrowing demand.
• Mainnet yield without gas fees. Users deposit EURC on Base and Solid routes it to Byzantine's vault on Ethereum mainnet, so they earn mainnet yield without paying Ethereum gas.
• An insured vault. Solid connects to Byzantine's insured Prime EUR vault, which carries third-party cover against defined technical risks.
• Control of their funds. Funds stay under the user's control, and positions can be verified onchain.

Byzantine: the infrastructure behind it

Byzantine provides the infrastructure that lets fintechs, wallets and neobanks add euro and dollar yield to their existing apps. Partners connect directly to Byzantine's vaults or through its API, test everything in a sandbox first, and keep their own customer experience. There is no need to build yield infrastructure or a strategy team in-house.

Solid chose to connect directly to Byzantine's vaults. The interface, the deposit flow and the withdrawal flow stay Solid's. The same infrastructure is used by companies managing their treasury on Byzantine.

About Solid

Solid is a non-custodial neobank built on Fuse. Users hold stablecoins, earn yield on dollars and euros, and spend anywhere Visa is accepted with up to 5% cashback, while keeping control of their keys and their funds. Euro cardholders can save and spend in euros with no FX fee. Learn more at solid.xyz.

About Byzantine

Byzantine is a Paris-based technology infrastructure provider that simplifies access to digital credit for financial institutions. Fintechs, wallets and neobanks use it to offer euro and dollar yield inside their own products, under their own brands. Today, more than 600 users across 10 countries rely on Byzantine's infrastructure, which has processed more than €23 million in transactions since launch.

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