Senior Front End Developer

• Important:

This position is
only for candidates legally residing in Poland
and operating under a registered sole proprietorship (JDG).

As part of onboarding, we kindly invite new joiners to our Warsaw office on the first day for a short introduction and identity verification.

Please note that applications from outside Poland cannot be considered.

Location
: Warsaw, Poland

Employment type:
B2B contract

Work model
: 100% remote

Business travel:
Occasional, up to twice per year

Sanoma Learning is the leading European learning company, serving over 20 million students in 11 countries. We offer printed and digital learning materials as well as digital learning and teaching platforms for primary, secondary, and vocational education. The development of our methodologies is based on deep teacher and student insight and really understanding their needs. By combining our educational technologies and pedagogical expertise, we create learning products and services with the highest learning impact. In our Technology organization, you will join the largest cross-cultural community of Sanoma Learning and contribute to the digital transformation and future of education in Europe.

Project Description
The SL Design System is a unified set of design principles, components, and tokens used to create consistent, accessible, and scalable user interfaces across all SL digital products. It includes guidelines for layout, typography, color, spacing, and interaction patterns, and is implemented in both Figma (for designers) and code (for developers). The system ensures visual and functional consistency, speeds up product development, and improves collaboration between design and engineering teams.

Role Responsibilities

• Develop and maintain Web Components for the design system using standards-based technologies (Custom Elements, Shadow DOM, HTML Templates).
• Ensure all components are accessible (WCAG-compliant), responsive, and work consistently across browsers and frameworks.
• Collaborate with designers to implement tokens, design specs, and interaction patterns into production-ready components.
• Write and maintain documentation, usage guidelines, and examples for developers and designers.
• Improve and maintain the component build pipeline (e.g., Rollup, Vite, or similar).
• Contribute to testing and validation (unit, integration, visual regression, and accessibility tests).
• Support product teams with guidance on adopting and integrating design system components.
• Participate in code reviews and promote standards-driven best practices for Web Components development.

Must-have Requirements

• Fluent in English
• Strong skills in JavaScript, TypeScript, HTML, and CSS.
• Proven experience developing Web Components (using standards or libraries like Lit, Stencil, or vanilla).
• Deep understanding of Shadow DOM, custom events, slots, and encapsulation patterns.
• Knowledge of accessibility standards (WCAG, WAI-ARIA) and best practices in component development.
• Familiarity with testing tools (Web Test Runner, Cypress, Playwright).
• Experience with version control (Git) and collaborative development workflows.
• Understanding of design tokens and how to implement them in component styling.

Nice-to-have Requirements

• Experience with Lit or other Web Component libraries.
• Familiarity with cross-framework integration (React, Angular, Vue wrappers for Web Components).
• Knowledge of performance optimization for components (lazy loading, bundling strategies, tree-shaking).
• Experience with Storybook, Pattern Lab, or similar for documenting and showcasing components.
• Contribution to open-source design systems or Web Component projects.

What We Offer
B2B contract for an indefinite period;

Work-life balance and great atmosphere;

Opportunities for professional development through interesting tasks.

As an employer, Sanoma offers a working environment where you are able and encouraged to show your best self. The working environment is result-oriented as well as flexible with a focus on collaboration. We offer you a key position with interesting and challenging tasks and excellent opportunities for professional growth. You will be part of a highly professional and experienced international team in an open and informal setting, where initiative is expected and rewarded.