Frontend Engineer

About TiJUBU At TiJUBU we're building the Living Company OS®: workforce intelligence that spans humans and AI agents. We help organizations see, rewire, and grow their workforce in real time, across skills, roles, mobility, pay, and purpose. We are early, defining a new category, and serious about building it well. We handle sensitive employee data across the EU, so reliability and privacy are core to the product, not an afterthought. The role This is our dedicated frontend seat. At our size that means the whole client surface is in front of you: the component system, the data-dense interfaces, the testing practice, and the everyday decisions about how things get built. You won't be doing this from a standing start. Our technical direction is decided and written down: Feature-Sliced Design, TanStack Query, Zustand, headless components with zero-runtime styling, a real design system in Storybook, Vitest coverage. Some of it is in flight, most of it is ahead of us, and you'll build it alongside our CTO rather than guess at it. The work is broad, the direction is clear, and how far you take it is genuinely up to you. High tempo, real ownership, and a scope that shifts as we grow. What you'll do Build and maintain the frontend of a multi-tenant B2B platform in React, TypeScript, and Vite, following Feature-Sliced Design.Build out the design system: Storybook and design tokens first, then the incremental migration to headless components and zero-runtime styling. This is a large piece of work and you'll be central to it.Turn dense workforce data into interfaces people understand: networks, matrices, hierarchies, distributions, and comparisons that stay legible at enterprise scale.Raise the testing bar. Vitest for unit and component work now, Playwright for end-to-end once the foundation holds. Coverage is currently what gates our framework upgrades.Move server state to TanStack Query, client state to Zustand, and forms to React Hook Form with Zod.Consume generated OpenAPI clients, and help shape API contracts with the backend before they're built rather than after.Build for enterprise reality: multi-tenant UI, SSO, role and attribute-based permissions rendered safely, large data imports, cross-browser support including Safari, and accessibility as a requirement rather than a nice-to-have.Modernize deliberately while shipping. Roughly half this role is careful improvement of what exists; the rest is new ground. What you'll bring 2 to 4 years building production frontend, ideally in a startup or another fast-moving environment.Strong React and TypeScript. You understand rendering behavior, not just the API surface.A working sense of state: server, client, and form state are different problems and you treat them that way.Comfortable building reusable components and working inside a component system.Comfortable with data-dense interfaces: tables, charts, hierarchies, and graphs rather than marketing pages.You write tests. Vitest, Jest, Testing Library, or equivalent.Performance and accessibility as things you consider by default.Git, code review, and CI/CD as everyday tools.The appetite to own things at a small company, and the judgment to ask before going too far alone.Professional English. Based in Portugal. Preferred Vite, Feature-Sliced Design, TanStack Query, Zustand, Ark UI, Panda CSS, Storybook, TanStack Table, Playwright.Experience contributing to or building a design system.Data visualization at real complexity: D3, canvas, or SVG at scale.Enough Node.js or NestJS to read the backend and argue about an API shape.Multi-tenant B2B SaaS, especially anything touching HR, payroll, or compliance data.Streaming and agentic AI interfaces.WebGL, Three.js, or p5.js for the more ambitious visualizations.Interest in mobile. It's on our roadmap, not on your first year. How we work Remote-friendly and Lisbon-based, in a close-knit team with direct founder access and real autonomy on hard problems. We design, pair, and review in the open, and AI is central to how we build. Birthday off. Compensation Salary, aligned with experience. Warm, precise, human. If this is you, let's talk.