Senior Frontend Product Engineer, Conversions (all genders)

HelloFresh; Warszawa; On-site; PLN 240,000 - 420,000; Full time

Benefits offered by this job

Workspace at Warsaw Centre Point

Job summary

HelloFresh’s HelloTech Warsaw team is seeking a senior frontend engineer to drive high‑performant web experiences. You will build personalized conversion pages using React, TypeScript, and edge runtimes, collaborating with machine learning, product and design to ship fast, reliable features for millions of customers.

You will work in a global, data‑driven environment, ensuring top Core Web Vitals, scalable architectures, and robust testing with modern tooling.

Qualifications

• Deep technical proficiency in React, TypeScript, and modern rendering patterns (SSR).
• Proven track record architecting solutions with edge runtimes and understanding impact on latency.
• GenAI expertise with modern AI tools to enhance speed and quality of work.
• Experience with A/B testing and feature flags in frontend contexts.
• Strong collaboration and clear communication across teams.

Responsibilities

• Drive architecture and delivery of personalized conversion pages and funnels using React/TypeScript/Next.js.
• Embed GenAI workflows into development, debugging, and quality processes to accelerate velocity.
• Ensure top-tier funnel performance, optimization of Core Web Vitals and low-latency personalization.
• Maintain the MarTech integration layer and GTM event pipelines feeding analytics/CRM.
• Implement robust automated testing with Jest and Cypress and frontend observability.

Skills

React

TypeScript

SSR

Edge runtimes

GenAI

A/B testing

Frontend observability

Tools

Vercel Edge Functions

Cloudflare Workers

Jest

Cypress

OpenTelemetry

Honeycomb

Grafana

Sentry

Job description

Work with HelloFresh in Warsaw and its HelloTech organisation, HelloFresh’s global technology backbone with more than 1000 people, building the digital products that power our end-to-end food experience. From meal kits and ready-to-eat meals to specialty offerings like pet food and premium meat & seafood, HelloTech creates the platforms that bring tailored food solutions to millions of customers every month. Our subscription-based, direct-to-consumer model relies on technology at every step, from customer-facing apps and personalization logic to pricing, forecasting, supply chain optimization, and initiatives that help reduce food waste. While our brands operate independently to serve distinct customer needs, they are united by shared platforms, data, and operational excellence built by HelloTech.

About the role: What's in the Box

Conversions Tech empowers HelloFresh Group meal brands to achieve ambitious growth targets through a seamless and high-performing conversion funnel. As part of the Growth Alliance, you will drive marketing innovation by delivering advanced MarTech capabilities, conversion optimization, and data-driven growth strategies. You will build personalized web experiences using React, Next.js, and edge environments, tailoring user journeys based on intent, channel, and campaign data. In this role, you will integrate with our CMS, leverage experimentation frameworks, and utilize GenAI tools, such as Claude, Cursor, Figma, and Contentful MCPs, to accelerate architecture, design, and testing workflows. Working alongside machine learning, product, and design experts, you will ensure high-performance execution, maintaining strong Core Web Vitals and low-latency delivery across global desktop and mobile applications.

What you’ll do: The Recipe

• Drive the architecture and delivery of personalized conversion pages and funnels using React, TypeScript, and Next.js, spanning SSR middleware design through to edge-layer caching strategies.
• Champion GenAI proficiency, embedding AI-driven workflows into development, debugging, and code-quality processes to accelerate execution velocity and output.
• Ensure top-tier funnel performance and application stability, optimizing Core Web Vitals, low-latency personalization, and multi-brand reliability at global scale.
• Architect and maintain the MarTech integration layer, behavioral lead-capture tools, and GTM event pipelines feeding downstream analytics and CRM systems.
• Implement robust automated testing strategies with Jest and Cypress, alongside frontend observability tools (OpenTelemetry, Honeycomb, Grafana, or Sentry) to embed deep traceability from initial design to release.
• Partner with cross-functional product, machine learning, and design experts to shape personalized user experiences and resolve complex technical trade-offs.

What you’ll bring: The Ingredients

• Deep technical proficiency in React, TypeScript, and modern rendering patterns (SSR), supported by extensive professional software engineering experience.
• Proven track record architecting solutions using edge runtimes (such as Vercel Edge Functions or Cloudflare Workers) and understanding how edge caching directly impacts personalization and latency.
• Demonstrated GenAI expertise, with hands-on skill leveraging modern AI tools and workflows to enhance code quality, development speed, and overall technical standards.
• Practical application of A/B testing and feature-flagging frameworks (e.g., Statsig, Optimizely) alongside frontend monitoring and observability platforms.
• Strong collaborative mindset with an ability to communicate complex technical decisions clearly, share knowledge with peers, and drive results autonomously across cross-functional domains.

Above all, we are looking for people who will make HelloFresh better. We believe there are many different ways of developing skills and we love diverse experiences! So even if you don’t “tick all the boxes” but think you’d thrive in this role, we would really like to learn more about you.

What we offer: The Toppings

• Global collaboration at scale: Collaborate with experienced engineers and product partners across HelloTech’s international teams, in a culture of active knowledge sharing.
• Technology with real-world impact: Build and operate modern systems at global scale, supporting 6+ millions of customers and complex supply chain operations.
• Technical/Product/Design leadership: Drive best practices and influence architecture/design, quality, and ways of working in an autonomous, product-led setup.
• End-to-end development/delivery: Drive decisions from problem definition to production, improving systems and enabling long-term scalability.
• Access to workspace at Warsaw Centre Point. The hub offers modern facilities including showers, breakout zones, outdoor space, cycle parking, and refreshments (coffee, soft drinks, and fruit).