The Bank for International Settlements (BIS) and central banks from France, Singapore, and Switzerland have completed Project Mariana, an experiment testing the cross-border trading and settlement of wholesale central bank digital currencies (wCBDCs) via decentralised finance (DeFi) on a public blockchain. The BIS Innovation Hub, alongside the Bank of France, Monetary Authority of Singapore, and Swiss National Bank, utilised a common token, bridges for wCBDC transfers, and an Automated Market Maker (AMM) to automate trade and settlement. Cecilia Skingsley, Head of the BIS Innovation Hub, emphasised the project's innovative approach to interbank foreign exchange. Despite its success, the initiative remains experimental, and the partner banks have made no commitments to issue wCBDCs based on the project's findings.