Freelance: Software Developer (Python, SQL, JavaScript, Next.js) Location: Leuven, Belgium (3 days onsite per week) Contract: Initial 12‑month freelance contract with likely extensions We’re looking for an experienced Freelance Software Developer to help build innovative digital tools supporting the sustainable transition of the semiconductor supply chain. You’ll work on developing new net‑zero features that give users full control over supply chain data, models, and impact calculations. Responsibilities : Design and implement new net‑zero features across a Python backend, SQL database, and JavaScript/Next.js frontend Collaborate closely with Life‑Cycle Assessment (LCA) experts to define data formats, architecture, and information flows Build functionality for downloading and uploading supply chain characterization data Ensure interoperability with other LCA tools while delivering a clear, user‑friendly experience Integrate your work into an existing large-scale codebase, continuously improving code quality Work closely with a cross‑functional software team Regularly demo progress and gather feedback from technical stakeholders Experience : Strong professional experience with Python Experience working in and extending large, collaborative codebases High standards for code quality, clarity, robustness, and maintainability Experience in one or more of the following is highly valued: Life‑Cycle Assessment tools or data formats (e.g. ILCD, Brightway, ecoSpold) SQL database design and management JavaScript and Next.js, with attention to UX/UI and user feedback Background in semiconductor manufacturing, materials, chemicals, or engineering is a plus Comfortable working both independently and as part of a team Proactive, creative, and accountable delivery mindset If this sounds like a good fit, please apply or reach out for a confidential discussion. We are happy to share further details about our client and the role.