Senior Fullstack React & Kotlin Engineer (Remote – Colombia/Costa Rica)

About the role

We are seeking a senior full‑stack engineer to build and evolve customer‑facing shopping experiences for a US‑based client. The role is fully remote and open to candidates residing in Colombia or Costa Rica.

Key responsibilities

• Design, develop and maintain scalable web applications using React and TypeScript.
• Build reliable backend services and APIs with Kotlin.
• Contribute to React Native mobile components when required.
• Own features from problem definition through design, implementation, testing, deployment and production support.
• Collaborate with product, design, analytics and engineering teams across the stack.
• Implement automated testing, observability, performance monitoring and safe deployment strategies.
• Troubleshoot production issues and participate in on‑call rotations.
• Document technical decisions and mentor junior engineers.

Required profile

• 5–8 years of professional software engineering experience, including production customer‑facing products.
• Deep expertise in modern web development with React and TypeScript.
• Strong understanding of frontend architecture, state management, accessibility and performance.
• Proven experience building backend services with Kotlin, designing APIs and data models.
• Familiarity with React Native and delivering consistent mobile experiences.
• Experience designing scalable, low‑latency distributed systems.
• Hands‑on knowledge of automated testing, observability and progressive deployment.

Required skills

• React
• TypeScript
• Kotlin
• React Native
• API design
• Data modeling
• Asynchronous workflows
• Service‑to‑service integration
• Automated testing
• Observability tools
• CI/CD pipelines