Senior Frontend Engineer

Treatwell

Senior Frontend Engineer at Treatwell handling complete frontend experience from design to operations. Collaborating with cross-functional teams and focusing on modern web technologies.

Posted 7/20/2026full-timeRemote • 🇪🇸 SpainSeniorWebsite

Core Competencies

Role fit

Core Competencies

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Demonstrates extensive experience in frontend development with a strong focus on modern web technologies, automated testing, and observability tools. Capable of leading technical discussions and collaborating effectively with cross-functional teams to enhance user experience and product quality.

Highest-signal resume keywords

Frontend DevelopmentAutomated TestingReactTypeScriptFrontend Observability

ATS Keywords

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Hard Skills

Frontend DevelopmentAutomated TestingReactTypeScriptMobile-First DesignAtomic Design PrinciplesEvent-Driven ArchitecturesCaching StrategiesPerformance MetricsError Tracking

Soft Skills

Excellent Communication SkillsProduct MindsetAnalytical ThinkingCollaborationResponsibility

Tools & Technologies

DatadogSentryWeb VitalsAI Tools

Industry Keywords

Frontend ExperienceUser ExperienceDesign SystemsResponsive Applications

Tech Stack

Tools & technologies

ReactTypeScript

About the role

Key responsibilities & impact

Take ownership of the frontend experience from design to deployment to operations.
Pair with engineers, designers, and PMs to ship features every cycle, iterating based on real usage and feedback.
Participate in design and code discussions, making trade-offs and decisions that affect the product and the team.
Maintain a strong focus on automated testing, applying the testing pyramid to ensure unit, integration, and end-to-end coverage.
Improve our frontend observability by adding metrics, dashboards, and alerts with tools like Datadog, Sentry, and web vitals to catch issues before they impact users.
Be an active part of the Frontend Guild, collaborating with other engineers to share ideas, improve standards, and tackle cross-team frontend challenges.
Lead technical discussions about trade-offs in features, architecture, and UX, helping the team make informed decisions that balance product goals and engineering constraints.
Navigate a hybrid codebase, balancing work between legacy systems and modern React/TypeScript.

Requirements

What you’ll need

7+ years of software development experience, with a strong focus on modern web frontend technologies.
You take responsibility for the code you write and the areas you own, spotting bugs, performance issues, or UX gaps, and fixing them proactively without waiting for direction.
You have a product mindset - you think about the person using what you build, ask why before how, and push back when something doesn't make sense
You actively leverage AI tools in your daily development workflow, viewing them as force multipliers for productivity, code quality, and problem-solving.
Excellent English communication skills - you can articulate complex technical ideas clearly to engineers, designers, and non-technical stakeholders.
Sharp product thinking and a focus on UX, paying attention to the little things - edge cases, empty states, error handling.
You are comfortable working with remote and co-located teams to deliver results.
Structured, analytical, and highly collaborative, particularly in a remote context.
Nice to haves
Frontend observability experience (Datadog, error tracking, monitoring, performance metrics, web vitals).
Experience with mobile-first design, atomic design principles, design systems, and progressive enhancement for responsive applications.
Full-stack mindset: you may not have actively written backend code, but you understand key architectural principles such as event-driven architectures, caching strategies, eventual consistency and how frontend and backend communicate effectively.
You’ve experimented with various forms of AI in product development and have opinions about where it could make products or workflows better.

Benefits

Comp & perks

28 working days holiday, plus local bank holidays
Monthly £/€40 Treatwell vouchers so you can treat yourself too
Mental health support through our partnership with Open-Up
Market-specific benefits that will be discussed in the interview process