Senior Mobile & Full-Stack Engineer (KMP) — Remote

Nix; Boston (MA); Hybrid; USD 120,000 - 160,000; Full time

Benefits offered by this job

Flexible working format

Competitive salary

Career growth

Professional development tools

Active tech communities

Education reimbursement

Anniversary presents

Corporate events

Job summary

N-iX in Boston is seeking a Senior Full Stack Mobile Developer to join Clint's team. You will build mobile features end-to-end and contribute backend services, APIs, and cloud components for scalable fintech applications.

Bring strong mobile experience, Kotlin Multiplatform preferred, plus Java/Kotlin with Spring Boot knowledge. You will mentor others, shape engineering practices, and collaborate across product, design, security and platform teams to deliver high-quality software.

Qualifications

• Proven mobile app development experience.
• Strong Kotlin skills and modern mobile architecture.
• Kotlin Multiplatform experience preferred but not required.
• Backend experience with Java 7+ and Spring Boot.
• Experience with APIs, microservices and cloud services.
• Experience with CI/CD, automated testing and production systems.
• Ability to own a feature from design to production.
• Strong communication and cross-team collaboration.

Responsibilities

• Build and improve mobile features used by real customers.
• Develop shared mobile logic using Kotlin Multiplatform.
• Build backend services and APIs with Java/Kotlin and Spring Boot.
• Work with cloud services, CI/CD, monitoring and production support.
• Improve performance, reliability, security, and UX.
• Use AI coding tools to assist development, testing, documentation, and debugging.
• Collaborate with product, design, architecture, security and platform teams.
• Mentor other developers and promote good engineering practices.

Skills

Mobile development

Kotlin Multiplatform

iOS/Android architecture

Kotlin

Java/Spring Boot

CI/CD

Job description

N-iX in Boston is seeking a Senior Full Stack Mobile Developer to join Clint's team. You will build mobile features end-to-end and contribute backend services, APIs, and cloud components for scalable fintech applications.

Bring strong mobile experience, Kotlin Multiplatform preferred, plus Java/Kotlin with Spring Boot knowledge. You will mentor others, shape engineering practices, and collaborate across product, design, security and platform teams to deliver high-quality software.