Staff Full Stack Engineer, Personalization (Kotlin/React)

About The Team:

The Personalization Squad is responsible for creating and enhancing the systems that power personalized user experiences across CookUnity’s platform. We focus on delivering tailor-made content, recommendations, and experiences based on user preferences and behaviors. By leveraging data and advanced algorithms, our team ensures that every interaction feels unique and relevant to the individual.

As part of the core engineering team, we collaborate closely with Data teams, Product Managers, and cross-functional stakeholders to build and maintain scalable, resilient systems that enhance user engagement. Our mission is to create personalized experiences that drive satisfaction, loyalty, and engagement for CookUnity.

To support CookUnity’s growth, we are continuously evolving our personalization systems to be more intelligent, data-driven, and adaptable. This is an exciting opportunity to solve complex engineering challenges, influence the future of personalized content, and have a direct impact on the experience of millions of users in a fast-growing digital ecosystem.

The Role:

As a Staff Full Stack Engineer on the Personalization Squad, you will play a crucial role in leading technical initiatives, driving architectural decisions, and mentoring engineers as we scale our user personalization infrastructure. You’ll work on a range of high-impact and technically challenging problems, including user preference modeling, behavior-driven recommendations, content delivery optimization, and personalization algorithms.

This is an exciting opportunity for an experienced engineer who thrives on complexity and enjoys designing scalable, resilient, and high-performing backend systems. You will collaborate closely with engineering leadership, product managers, and cross-functional teams—including Data teams—to build and improve mission-critical infrastructure that enables personalized user experiences across our platform. Together with Data teams, you will develop data-driven solutions that transform user behavior insights into seamless, personalized content delivery.

We’re looking for someone who can bring strong system design expertise, lead projects from concept to deployment, and set a high technical bar for the team while driving forward best practices in software engineering. You’ll have the opportunity to work on key aspects of our personalization engine that directly enhance user engagement and satisfaction by leveraging data-driven insights and collaboration.

Our Tech Stack:

• Languages: JavaScript and Kotlin
• Frameworks: ReactJS, Redux, NodeJS, Express, GraphQL.
• Databases: MySQL & PostgreSQL.
• Infrastructure: AWS Based: Kubernetes, S3, CloudFront and RDS.
• Agile Methodology

Please note that only candidates based in Latin America will be considered for this role.

Responsibilities:

• Lead the design and implementation of scalable backend services that power CookUnity’s personalization systems.
• Define and drive architectural improvements that enhance system reliability, scalability, and maintainability.
• Collaborate cross-functionally with Product and Data teams to provide our users tailor-made content that adjust to their needs.
• Mentor and guide other engineers, setting a high standard for technical excellence and a culture of proactive ownership.
• Evaluate and introduce new technologies, frameworks, AI adoptions that improve our backend stack and development velocity.
• Improve system observability, performance, and resilience, ensuring uptime and smooth operation of revenue-critical systems.
• Contribute as a hands-on engineer, writing clean, well-tested, and efficient code, leading by example.
• Lead technical planning and project execution, breaking down complex problems into manageable solutions and driving initiatives to on-time completion.

Minimum Requirements:

• 8+ years of experience in software development, with expertise in Kotlin, React and SQL databases (PostgreSQL or MySQL).
• Proven experience in architecting and scaling complex backend systems in a high-growth, fast-paced environment.
• Strong knowledge of distributed systems, service-oriented architecture, and event-driven architecture.
• Deep understanding of system performance and scalability best practices.
• Proven ability to translate complex, ambiguous requirements into clear, actionable plans that drive alignment and timely delivery.
• Advanced English communication skills, with the ability to clearly articulate complex ideas to both technical and non-technical audiences.
• Demonstrated experience in mentoring and guiding engineers.

Preferred Requirements:

• Experience implementing or integrating machine learning models for personalization, such as recommendation algorithms, user clustering, or predictive analytics.
• Familiarity with data pipelines, data lakes, and working with large-scale datasets. Understanding how to work with Data teams to ensure data availability, quality, and consistency in a personalized recommendation system.
• Experience with DevOps tools and cloud platforms, including Docker, Kubernetes, and AWS.

Benefits:

💸 Get paid in USD. Whatever your choice! We use Deel to make things easier for you!

🗺 Work remotely: design the life that you want.

⛱ Enjoy 15 business days of vacation each year from the start date.

🩺 Healthcare Benefit: Monthly stipend to use in your preferred healthcare provider.

🎄 16 fully paid Argentinean holidays.

🕯 Compassionate Leave: 3-5 days each time the need arises.

🐣 Family leave of 12 weeks for primary caregiver and 6 weeks for secondary caregiver, fully paid.

🧑‍🏫 Personalized English coach.

🧘🏻‍♀️Customize the benefits that suit your needs! Access a range of perks tailored to you, including learning opportunities, wellness memberships, delivery apps, and more through our comprehensive benefit platform.

🗓️ 5- year Sabbatical: After 5 years with CookUnity, you get a 4-week paid sabbatical.