Principal Software Engineer - Global UX - Application - Platform

Title: Principal Software Engineer - Global UX - Application - Platform Location: Spain

What is The Role

In this role, you will provide technical leadership for the Global UX engineering team, the group responsible for Elastic UI (EUI) - Elastic's design system and React component library - and the shared patterns, tokens, and tooling that give Elastic products a consistent, accessible, and high-quality experience.

EUI underpins the UI of every major Elastic product. As Tech Lead, you will set technical direction for how the design system scales across dozens of consuming teams, mentor and grow the engineers around you, and act as the senior-most technical voice connecting design intent to component architecture. This is a hands-on leadership role: you will write and review code, make the hard architectural calls, and also be the person other engineers and designers turn to when a component API, theming strategy, or migration path needs to be figured out.

We are looking for a Principal Software Engineer with deep expertise in React, TypeScript, and component library architecture, who has built or led design systems at scale, and who combines strong technical judgment with the leadership skills to align a team, a roadmap, and a community of internal consumers around a shared direction.

What You Will Be Doing

• Provide technical leadership for Elastic UI (EUI), setting direction for component architecture, API design, theming, accessibility, and long-term maintainability across a design system consumed by many product teams.
• Own the hardest technical decisions in the system: composable component patterns, breaking-change and migration strategy, versioning, token architecture, and the tradeoffs between flexibility and consistency.
• Act as tech lead for the Global UX engineering team - setting technical standards, reviewing designs, unblocking engineers on difficult problems, and ensuring the team's work ladders up to a coherent long-term architecture.
• Partner closely with design leadership to translate design language, visual direction, and interaction patterns into robust, reusable, well-documented component APIs.
• Drive adoption of the design system across Elastic by working directly with consuming teams, understanding their constraints, and evolving EUI's APIs and documentation so adoption is easy rather than forced.
• Raise the bar on accessibility, performance, and cross-browser correctness for shared UI building blocks used throughout Elastic's products.
• Mentor and grow engineers on the team through code review, design critique, and pairing, and help develop the next generation of senior and staff-level engineers.
• Represent the Global UX team in cross-functional planning with product, design, and engineering leadership, and make the case for investment in design system health and developer experience.
• Use profiling, telemetry, and feedback from consuming teams to identify where the design system is creating friction, and lead the initiatives that fix it.
• Explore how AI can improve the design-to-code workflow - for example, component generation from design specs, automated accessibility checks, or AI-assisted migration tooling - while holding the team accountable for the quality and correctness of shipped components.

What You Bring

• Deep, hands-on expertise building and operating React and TypeScript component libraries or design systems in production, at a scale with many internal or external consumers.
• A strong track record of technical leadership - setting architecture, raising quality standards across a team, and making decisions that other engineers align behind without needing formal authority.
• Experience designing composable, flexible component APIs, including patterns like compound components, render props, headless components, and theming/token systems.
• Strong instincts for accessibility (WCAG, semantic HTML, keyboard and screen-reader behavior) and a track record of building that rigor into a team's default practices.
• Experience managing the lifecycle of a widely-consumed library: releases, breaking changes, deprecation and migration paths, and documentation that keeps adoption smooth.
• Ability to partner directly with designers and design leadership, translating visual and interaction intent into technical constraints and component contracts.
• Excellent judgment about when to invest in reusable abstractions versus one-off solutions, and the communication skills to explain those tradeoffs to both engineers and non-technical stakeholders.
• A history of mentoring engineers and elevating the technical level of a team, through code review, design docs, and pragmatic, hands-on leadership.
• Experience working transparently in a distributed team - clear written communication, async-first collaboration, and open-source or open development practices.
• Curiosity about how AI can improve design system workflows, paired with the judgment to hold a high bar for correctness and quality in whatever ships.