Lighthouse Codes for HPC Applications

The Lighthouse Codes for HPC Applications will play a strategic role in developing globally competitive HPC application software and accelerating Europe's leadership in high-performance computing (HPC) applications. By integrating cutting-edge capabilities into production-grade software, these codes will enable scientific discovery, and drive cross-sector innovation. They will ensure long-term sustainability and scalability of Europe's HPC ecosystem.

This initiative will result in collaborations between researchers, industry, and HPC experts, promoting best practices in software development, optimization, and interoperability. By aligning with scientific grand challenges (e.g. fusion energy, development of high-capacity/low-cost batteries, AI-driven genomics-based personalized treatments or AI-driven cybersecurity), Lighthouse Codes will contribute to breakthroughs in scientific, industrial, and societal applications, strengthening Europe's technological autonomy and innovation capacity in the exascale and AI era.

Expected outcomes include:

• Successful integration of cutting-edge capabilities into production-grade software, driving innovation and enhancing Europe’s scientific excellence and industrial competitiveness.
• Enhanced scientific and engineering productivity: Consolidated and optimized Lighthouse Codes lower technical barriers, enabling faster and more accurate simulations and computations. This supports scientific discovery, advances engineering solutions, and drives cross-sector innovation.
• Well-documented, high-quality codebases with well-defined scope and functionality, passing rigorous validation and reproducibility standards.
• Stronger alignment with EU grand challenges, ensuring that Lighthouse Codes contribute to Europe’s strategic priorities in science and industry.

Central objective is the strategic and focused development of globally competitive HPC codes with high impact. This includes:

• further developing existing Lighthouse Codes,
• but also consolidating, refactoring, redesigning or rewriting existing applications, which will result in a state-of-the-art Lighthouse Code during the implementation of the proposal, and making the Lighthouse Code accessible to the wider HPC user community.

"Lighthouse Code" refers to an application, a software development kit (SDK), or a software library which is distributed as a single package and meets the following broad criteria:

• Established professional software development and management structures involving professional HPC software engineers, including policies to ensure quality, coherence and compliance of contributions with community standards and best practices.
• An established large or rapidly growing user community, demonstrated through appropriate KPIs (e.g., number of users/growth trend, downloads, HPC resource allocations).
• Processes for systematic documentation as part of the development process providing comprehensive documentation of functionality, ensuring usability for both users and developers, including APIs, user manuals, and developer guides.
• Commitment towards code stewardship by at least one eligible legal entity, ensuring ongoing maintenance, updates, and strategic development beyond the grant period.
• Competitive scalability in the respective domain, and availability across multiple supercomputing architectures, including heterogeneous and accelerated platforms.
• Potential for broad adoption and high-impact applications in scientific, industrial or societal domains.
• Ownership and licensing framework, allowing both open-source and proprietary codes to be included, provided that access and development rights are clearly defined and consortium members demonstrate the competence to control and further develop the code.

The software developments will establish best practices among European contributors and lead to sustainable, globally competitive software that can significantly impacts the wider HPC ecosystem.

Lighthouse Codes are expected to demonstrate potential collaboration with relevant Centres of Excellence (CoEs) and the EuroHPC Academy, where appropriate, to benefit from the European community building and training efforts in key HPC domains.

This call builds upon and complements HORIZON-EUROHPC-JU-2023-COE-03-01 and HORIZON-EUROHPC-JU-2023-COE-01-01 and should associate where relevant with the following actions: HORIZON-JU-EUROHPC-2026-COE-LH-01-01 and HORIZON-JU-EUROHPC-2026-COE-LH-01-02.

Proposals should specify and describe the Lighthouse Code in detail. In this regard, communities are invited to present proposals which consolidate efforts dedicated, e. g. to multiple domain science codes, into one common Lighthouse Code.

Proposals clearly identify and describe the Lighthouse Code(s) to be developed or consolidated which must either already exist or, in exceptional and well-justified cases, be a state-of-the-art reimplementation of functionality of existing code. Each proposal may include only one Lighthouse Code. If an entirely new Lighthouse Code is proposed, it must be based on existing applications with high impact, for example in science and technology, and demonstrate a credible potential to meet the Lighthouse Code criteria within the project’s duration.

Proposals should focus on the development, consolidation, or expansion of a Lighthouse Code with clearly demonstrated scientific, technical, or societal impact. A robust software development plan, including a well-defined scope, timeline, and sustainability strategy, should be central to the proposal.

Proposals should focus on at least one of the following activities, with clear, measurable KPIs and a detailed software development plan including regular milestones for all development lines:

• Code Development & Optimization: rewrite, transform or consolidate multiple codes with existing large user communities and high scientific impact into one, potentially new Lighthouse Code.
• Consolidate, or integrate multiple high-impact codes to improve performance, usability, and sustainability within the HPC ecosystem.
• Feature Enhancement: Implement new functionalities in an existing Lighthouse Code to extend its capabilities and improve usability.
• Architecture Adaptation: Port Lighthouse Codes to new HPC architectures, including novel accelerator-based platforms.
• Exascale/ AI Readiness: Implement post-exascale/ Advance AI capabilities, improving scalability and efficiency.

Additional requirements:

• Consortia should include a balanced composition of partners, integrating HPC specialists and domain experts with relevant expertise.
• Maximize impact through collaboration, establishing strong links with other actions supported under this call.
• Commitment towards the sustainability of the codes beyond the grant period which should be demonstrated by a letter of commitment from a participating legal entity that will provide stewardship for the Lighthouse Code.
• The participation of entities in the private sector is strongly encouraged, provided alignment with central business objectives is clearly demonstrated.
• Proposals should describe in detail how the software development process will be streamlined and managed, including all relevant IT tools e. g. for code and documentation management, test automation, quality assurance, continuous integration, continuous delivery, issue trackers, user feedback and monitoring dashboards. Applicants are encouraged to use best practice and automated workflows where appropriate to reduce administrative overhead and improve continuous reporting effort towards EuroHPC.
• Proposals should define and describe a mechanism how the specific developments resulting from the proposed work can be identified in the code.
• While deviations are permissible if adequately justified, proposals should generally allocate at least 12 person months of resources for portfolio activities. The portfolio activities, which refer to collaboration tasks with relevant initiatives under the same call, will be defined after the evaluation and implemented through a dedicated work package or task in the final Grant Agreement.
• While deviations are permissible if adequately justified, the overall resources allocated to non-technical work, such as project management, coordination, dissemination should generally not exceed 2% of the overall personnel resources. All participants are expected to contribute substantially (at least 5% of the total personnel resources) to the technical work and take responsibility for associated tasks and deliverables.