Senior Frontend Developer | Starszy Programista in London

Sensor Tower’s digital intelligence platform provides unparalleled insight into market trends, advertising, competitor’s strategies, and consumer/user audience across mobile, web, and gaming. Sensor Tower’s insights are trusted by more than 2,500 enterprises worldwide across tech, retail/commerce, entertainment/media, gaming, consumer packaged goods, finance, and investment.

As a Frontend Engineer at Sensor Tower, you will not only build features, you will define how we build them. In our lean and flat organization, your voice will shape the technical direction of our product, helping us deliver an intuitive, fluid user experience that helps our customers understand the digital ecosystem.

• Architect and deliver complex, scalable frontend systems that are simple and effective, removing unnecessary complexity from our codebase.
• Mentor junior and mid-level engineers through code reviews, pair programming, and by instilling quality-first habits across the team.
• Take ownership of the frontend stack by proactively identifying bottlenecks, technical debt, or systemic issues and driving the initiatives to fix them.
• Advocate for and drive best practices in React, TypeScript, and web performance optimization across the engineering organization.
• Collaborate deeply with Data Science and Backend Engineers to ensure seamless data flow and end-to-end system reliability, and use these partnerships to progressively expand your expertise across the full stack.

4+ years of software engineering experience with a deep specialization in modern JavaScript, TypeScript, and React.

• While our stack relies on TanStack Query, React Router and Zustand, we value engineers who understand the principles and can adapt expertise from other libraries like Redux, MobX, NextJS.
• You can design systems that handle complexity without becoming complicated, prioritizing long-term maintainability.
• Competence in writing robust and efficient unit and integration tests using frameworks like Jest or Playwright.
• Deep understanding of web performance, browser internals, and optimization techniques for data-heavy applications.
• You are comfortable pushing back on requirements and proposing alternative solutions that drive better business outcomes and user experiences.

Experience in data visualization and analytics (handling large datasets, heavy DOM manipulation with libraries like Highcharts).

A portfolio, GitHub history, or technical writing that demonstrates clean code, an eye for design, and the ability to solve complex architectural challenges.

Familiarity with back end frameworks Ruby on Rails/Angular and different types of DBs (Clickhouse, Mongo, Postgres).

Knowledge of AI-driven coding tools and models as we encourage leveraging AI to enhance coding efficiency and unlock creative potential.

Our flexible work environment allows employees to live in greater connection with the people, places, and activities they love! Flexible time off so employees can shape their time away from work.

We are committed to equal employment opportunities regardless of race, color, ancestry, religion, sex, national origin, sexual orientation, age, citizenship, marital status, disability, gender identity, and veteran status. If you have a disability or special need, please do not hesitate to let us know and we'll do our best to accommodate.