The QLSI2 FPA proposal consists of 23 partners from 9 different countries, with one of the partners under associated country ownership. By integrating the QLSI2 consortium into the global European quantum ecosystem of complementary European and national consortia, a strong synergistic European partnership will be established with the ambition to demonstrate a cloud-accessible full-stack quantum computer with at least 1000 semiconductor-based qubits by 2029. The QLSI2 partners will leverage the expertise of key European players (RTOs, academic laboratories, start-ups and large companies) in complementary fields of quantum technologies, from hardware to software, to define and implement a roadmap towards such an ambitious goal. The roadmap will extend its vision to the entire value chain, including the supply chain. Particular attention will be paid to the industrialisability of the proposed solution in order to keep Europe at the forefront of the race for quantum supremacy for a long time to come. The roadmap will be implemented in the Specific Grant Agreements (SGA) that will be awarded under the FPA upon its successful completion. In addition to demonstrating large-scale semiconductor-based quantum computers, these SGA will aim to advance both technology and manufacturing readiness to a level high enough to meet Europe's ambitions for its quantum computing capability.