Senior Frontend Engineer
Posted on December 10, 2025 (about 2 hours ago)
About Flo
Flo is the world’s #1 health & fitness app worldwide on a mission to build a better future for female health. Backed by a $200M investment led by General Atlantic, Flo became the first product of its kind to reach a $1B valuation in 2024. It has over 500 million downloads and 77 million monthly users.
Flo has 6 million paid subscribers and the highest-rated experience in the App Store’s health category. The company is now building the next generation of digital health, with AI-powered, privacy-first, clinically backed features to help users understand their bodies better.
The job
Flo is seeking a Senior Frontend Engineer to build the next generation of Flo’s platform and user experiences. The role involves working on the foundation that powers interactive surveys and dynamic content inside the Flo app, including building SDKs, reusable components, and internal tooling for other product teams to deliver exceptional experiences quickly and reliably.
The frontend stack is based on React, TypeScript, and Next.js, with a strong focus on performance, maintainability, and testing. The team uses TypeScript for type safety, Jest and Playwright for automated testing, and continuously evolves the design system and UI Kit.
Responsibilities
- Design, build, and maintain high-quality user-facing components and platform SDKs that enable survey and interactive experiences in the Flo ecosystem.
- Collaborate with product, design, and backend engineers to deliver flexible and scalable solutions.
- Contribute to Flo’s design system and shared UI libraries to ensure consistency and reusability across products.
- Refactor and improve existing codebases for performance, reliability, and maintainability.
- Write clean, modular, well-documented code and advocate for engineering best practices.
- Actively participate in the frontend community at Flo by sharing ideas and driving improvements in architecture and development processes.
Required Experience
- 7+ years of experience building, shipping, and maintaining modern web applications.
- Expert-level knowledge of HTML, CSS, and JavaScript (ES6+).
- Deep experience with React and modern frontend tooling.
- Proven ability to create adaptive, responsive, and accessible user interfaces.
- A product mindset and strong collaboration skills with a focus on user impact.
Preferred Experience
- Familiarity with Next.js, Contentful, or similar frameworks and CMS solutions.
- Experience with A/B testing and experimentation frameworks.
- Understanding of analytics and BI integrations.
- Exposure to continuous delivery pipelines and web automation tooling.
- A good sense of design and usability.
Work Culture and Benefits
Flo is a mission-led, product-driven team that moves fast, stays focused, and takes ownership. The team values debate, shared decisions, craftsmanship, purpose-driven shipping, and continuous improvement.
Employees work with committed, resilient colleagues who prioritize better health outcomes.
Benefits include competitive salary with annual reviews, performance incentive schemes, paid holiday, sick leave, female health leave, enhanced parental leave, accelerated professional growth, flexible working arrangements, a 5-week fully paid sabbatical, Flo Premium for friends and family, and other health, pension, and wellbeing perks.
Diversity and Inclusion
Flo is an equal opportunity employer that hires based on merit and skills. The company welcomes applicants from all backgrounds, communities, and identities. They have a privacy notice for job applicants available on their website.
How to Apply
Applicants can apply for the Senior Frontend Engineer position through the job posting platform on the Flo Health Greenhouse page. They will need to fill in required fields such as first name, last name, email, location city, LinkedIn profile, and confirm their review of the privacy notice and willingness to be contacted about job opportunities.
Applicants should be currently based in Lithuania and within commutable distance to Vilnius, willing to visit the office occasionally as the company aims for higher in-person, office-based work cadence to build culture and relationships.
The application form allows attachment of resumes/CVs and cover letters in accepted file types including pdf, doc, docx, txt, and rtf. Applicants must confirm their agreement to the company's privacy policy for job applicants as part of the submission.
More details and exact application steps are found on the posting page.