Central Bank Digital Currencies (CBDC) envisioned by the European Central Bank, leveraging hash links, trigger chains, and Appia technology for tokenization.

Central Bank Digital Currencies (CBDC) envisioned by the European Central Bank, leveraging hash links, trigger chains, and Appia technology for tokenization.

The European Central Bank (ECB) has embarked on a significant journey towards the development of wholesale central bank digital currency (wCBDC) using distributed ledger technology (DLT). This journey, known as the dual-track approach, consists of two projects: Pontes and Appia.

In the short term, Pontes is the focus. It aims to provide a market-ready DLT settlement solution, linking DLT platforms with TARGET Services (the Eurosystem’s payment system) to settle transactions in central bank money. The ECB plans to launch a pilot for Pontes by the end of the third quarter of 2026. This pilot will offer a single Eurosystem solution, incorporating features tested during 2024 exploratory work on DLT, and will further explore enhancements compliant with TARGET Services’ operational, legal, and technical standards.

Pontes will connect the Eurosystem DLT with market DLTs via an Extended Interoperability Interface with API Gateway. The Delivery-versus-Payment system (DvP) based on the Hash-Link protocol will be used in Pontes. A trigger backend is employed in Pontes, which introduces a trigger chain connected to market DLTs. The trigger chain in Pontes passes the business event of a transaction of tokenized assets to create and send the (classical) payment to T2.

Meanwhile, Appia represents the longer-term track. Its stated goals include increased security, efficiency, market integration, and strengthening the euro in the international sphere, even in the DLT ecosystem. The decision between the two basic architectures of Appia, Shared/Single Ledger and Full Interoperability/Interoperable Ledger, is not only technical but also influenced by legal and operational questions.

The Shared/Single Ledger option unites central bank money and all relevant financial instruments, enabling seamless, automated workflows, especially DvP. On the other hand, the Full Interoperability/Interoperable Ledger option coordinates several independent DLT systems, but synchronizes during settlements. Central questions, especially regarding technical design and legal frameworks, remain open in the development of Appia.

The development of Pontes is led by the German, French, and Italian central banks, who previously tested their own solutions. Market opinion is playing a significant role in the development of Appia through close collaboration with market participants. The ECB's long-term project, "Appia," aims to go beyond Pontes and modernize the European financial system based on DLT.

The launch paper for Appia is expected in H1 2026, aiming to clarify several aspects, particularly the scope, fundamental principles, and interoperability function. No further information about the launch date or details of the "Appia" ecosystem is provided at this time. The ECB's interim solution "Pontes" for wCBDC is expected to launch on July 15, 2026.

This dual-track approach reflects the ECB’s commitment to supporting innovation in financial market infrastructures while maintaining safety and efficiency. It also aims at interoperability between traditional financial systems and new DLT-based markets by connecting DLT platforms to existing Eurosystem payment services, thus facilitating smooth settlement of digital financial assets. Between now and the Pontes pilot launch, the ECB will consider additional DLT-related trials and experiments to inform this integration.

In the long term, the European Central Bank's (ECB) project, Appia, aims to modernize the European financial system using distributed ledger technology (DLT) and interoperate with other industry sectors, particularly finance and technology. Together with market participants, the ECB will develop Appia, aiming to go beyond the Pontes interim solution and create a more integrated and efficient DLT-based market.

While Pontes concentrates on providing a DLT settlement solution for central bank money using the Hash-Link protocol, Appia builds upon this foundation and focuses on increased security, market integration, and strengthening the euro's position in the global sphere. The ECB's approach to wCBDC development is guided by the need for innovation in financial market infrastructures while ensuring interoperability, safety, and efficiency.

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