> Markdown version of [/jobs/ext/2777807-performance-rendering-engineer](https://www.wearedevelopers.com/jobs/ext/2777807-performance-rendering-engineer). Every page supports `.md` or `Accept: text/markdown`. Links point to the HTML versions so they work for humans too. Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Performance & Rendering Engineer - **Company:** Trabajos En Kaleidos - **Location:** Madrid, Spain (Remote available) - **Salary:** €60,000.0 - €67,000.0 - **Contract:** Permanent contract - **Skills:** HTML, JavaScript (Programming Language), Adobe InDesign, Application Programming Interfaces (APIs), Agile Methodology, Artificial Intelligence, Lisp (Programming Language), C++ (Programming Language), Cascading Style Sheets (CSS), Clojure, Cursor (Graphical User Interface Elements), Web Development, Text Processing, Video Game Development, Game Engine, Linux System Administration, Open Source Technology, E2e Testing, Large Language Models, Rendering Engine, Cypress (Programming Language), Backend, Playwright, Front End Software Development, Functional Programming, GPT - **Published:** September 7, 2026 - **Apply:** https://www.adzuna.es/contact-us.html ## About the Role We believe that education can be acquired in many ways, not just through a degree. That's why we don't require specific formal education, but we do expect you to have senior experience in the following areas: + Rendering engines. Here you'll find WASM, Rust, and Skia (so it's great if you have experience building game engines, graphics libraries, rasterization, GPU pipelines...). You don't need to be an expert in these specific technologies or in graphics APIs, but you should have definetely worked with them before, and feel comfortable getting better at them. + Hands-on experience with frontend technologies, with a good command of JavaScript, browser APIs, HTML, and CSS. + Regular use of LLMs (Claude, Cursor, ChatGPT, OpenCode...) as part of your way of working, among other things to make it easier for you to interact with and integrate into Penpot's Clojure core. We've brought AI into our development processes and we have open discussions and workstreams focused on finding the best way to use AI, taking into account many different aspects (technological possibilities, digital sovereignty / open source, ethics...). + Comfortable working in Linux environments. + Languages: high level of spoken and written English and Spanish. We need you to be able to read and write technical documentation and speak functionally in English, since it's the first language for some kaleiders. It's also necessary that you know Spanish (spoken and written), since many team meetings are held in this language. An example of someone who'd fit great with the team: someone with experience in graphics engines or in-browser game development (using graphics APIs); or maybe someone strong in WASM, with C++ or Rust, with an interest in working in graphics environments... does that sound like you? ;) Earn extra points + Familiarity with Clojure or other functional languages (Scheme, Lisp...). + Knowledge of JavaScript testing (Jest, Cypress...) and end-to-end tests with Playwright. + Interest in solving user problems with new languages and frameworks. + Interest / knowledge in accessibility and responsible development. + Interest / knowledge in design systems and their integration with product development. + Previous experience or genuine interest in open-source projects. + Use of agile methodologies in a professional environment. + Background of collaboration in diverse teams (design, marketing, backend...). + Ability to ask the right questions to help product development. + Care for testing your own code responsibly (unit, integration, and end-to-end tests), to help reduce production incidents. ## Description You'll be part of a small team working in Rust on Penpot's rendering engine (built with WASM, Rust, and Skia), on the text editor, and on ongoing performance improvements. Your work will be focused on fixing bugs, improving performance, and building new features for that engine. Performance is the main focus: help us make Penpot run smoothly in the browser, with response times as fast as possible. You'll also have some points of contact with the frontend, mainly when it comes to passing data between Clojure and the engine. That's why you need to feel comfortable with web programming and with the fundamentals of functional programming. We're looking for someone with senior, solid, consolidated experience, to work within a horizontal team with no manager figure: autonomy and shared decision-making are part of the role., You'll regularly work with Elena, Alex, Belén, Andrey, and Alonso, and you'll be in touch with the other software developers and creators of Penpot within the product team. You'll also have periodic cross-team meetings to keep up with the state of the business and the product with other Kaleidos / Penpot teams. ## Related Videos - [ Evaluating AI models for code comprehension](https://www.wearedevelopers.com/videos/1462-evaluating-ai-models-for-code-comprehension) - [The Resilience of the World Wide Web](https://www.wearedevelopers.com/videos/1281-the-resilience-of-the-world-wide-web) - [Developing the Backend with Stefan Lingler, CTO at Shpock](https://www.wearedevelopers.com/videos/100360-developing-the-backend-with-stefan-lingler-cto-at-shpock) - [Rendering Design Software in the Browser at Penpot](https://www.wearedevelopers.com/videos/1353-rendering-design-software-in-the-browser-at-penpot) - [Streaming AI Responses in Real-Time with SSE in Next.js & NestJS](https://www.wearedevelopers.com/videos/1630-streaming-ai-responses-in-real-time-with-sse-in-next-js-nestjs) - [Building Collaborative Open Source tools for Developers and Designers - Pablo Ruiz-Muzquiz from Penpot](https://www.wearedevelopers.com/videos/1345-building-collaborative-open-source-tools-for-developers-and-designers-pablo-ruiz-muzquiz-from-penpot) ## Related Articles - [Dev Digest 120 - Apple and peers](https://www.wearedevelopers.com/magazine/455-dev-digest-120-apple-and-peers) - [Dev Digest 121 - AI goes offline](https://www.wearedevelopers.com/magazine/456-dev-digest-121-ai-goes-offline) - [Dev Digest 131 - AI'm not sure about OSS](https://www.wearedevelopers.com/magazine/472-dev-digest-131-ai-m-not-sure-about-oss) - [Dev Digest 123 - Easy as A, B, C1](https://www.wearedevelopers.com/magazine/459-dev-digest-123-easy-as-a-b-c1) - [Dev Digest 129 - Now that's what I call private data!](https://www.wearedevelopers.com/magazine/468-dev-digest-129-now-that-s-what-i-call-private-data) - [Dev Digest 118 - not a total recall](https://www.wearedevelopers.com/magazine/452-dev-digest-118-not-a-total-recall)