Data exchange, monetisation and trading should be safe, fair and interoperable. This is essential in the digital data market. The EU-funded UPCAST will provide a set of universal, trustworthy, transparent and user-friendly data market plugins. These will enable actors in the European data spaces to design and deploy data exchange and trading operations. To ensure the automation of data sharing and processing agreements between businesses, public administrations and citizens, the project will pave the way for the automatic negotiation of agreement terms and improve data-asset discovery. UPCAST will also cover commercial and administrative confidentiality requirements, and provide low environmental footprint. Four real-world pilots across Europe will operationalise a set of working platform plugins for data sharing, monetisation and trading.