Kaleidos is the company behind Penpot, the first open-source design platform built for design and code teams to work together at the same scale. We're a horizontal organisation, with no traditional hierarchy, and our values are rooted in open-source principles, alongside honesty, feminism, work-life balance, transparency, generosity and joy in what we do. At Kaleidos, we have a genuine commitment to diversity in all its forms. Our team is made up of more than 50% women, and we'd love to welcome new colleagues who share our values, from whom we can keep learning and with whom we can keep building Penpot. At Penpot, you'll take part in a range of projects and features across the product, with a strong focus on solving real problems identified by our users: improving their experience through new features, tackling pain points and bugs, and delivering quick wins with a direct impact on their day-to-day work. You'll be able to move across different parts of the product, so you'll quickly get up to speed with the context behind each problem and propose solutions that work for Penpot users worldwide. We're looking for someone with solid, well-established experience. You'll work within a horizontal team, where autonomy and shared decision-making are part of the role. We believe expertise can be gained in many ways, not just through a formal qualification. That's why we don't require a specific degree, but we do expect experience in the following: Interest in or experience with reactive programming (at Penpot we use RxJS). A background as a frontend developer (backend-for-frontend), with solid command of JavaScript, browser APIs, HTML and CSS, and experience with JS frameworks (we mainly use React). Motivation to build robust, carefully crafted user interfaces. Knowledge of, and hands-on experience with, functional programming. Day-to-day work is in ClojureScript, but you don't need to master it from day one: you can learn it as you go, drawing on LLM tools for support. Regular use of LLMs (Claude, Cursor, ChatGPT, OpenCode...) as part of how you work. We've recently introduced agents into our day-to-day, and we keep an open, ongoing conversation about the use of AI. Comfortable working in Linux environments. Languages: a high level of spoken and written English. You'll need to read and write technical documentation, and speak with fluency and precision, as English is the first language for some kaleiders. You'll also need a functional level of Spanish (spoken and written), as many team meetings take place in this language.