Newxel

We are looking for a Senior Full-Stack Engineer (Kotlin + React) to join a team building a cybersecurity product.

In this role, you will take ownership of full-stack development, contribute to architectural decisions, and support the growth of the engineering team. This is a good fit for someone who is comfortable working in a startup environment, takes initiative, and enjoys solving complex technical challenges.
 

Responsibilities

• Design, build, and maintain full-stack applications using Kotlin (backend) and React (frontend)
• Work with Docker and containerization as part of deployment and DevOps tasks
• Contribute to architectural decisions as the product evolves and scales
• Mentor junior and mid-level engineers and support team growth
• Participate in on-call rotations and handle critical security issues when they arise
   

Requirements

• 5+ years of professional software development experience
• Strong experience in Kotlin backend development
• Strong experience in React frontend development
• Hands-on experience with Docker and containerized environments
• Agile mindset with the ability to work across both backend and frontend, adapting to changing priorities
• English — Upper-Intermediate (B2) or higher
   

Will be a plus

• Experience in cybersecurity or a strong interest in the domain
• Experience with WebSockets or real-time systems
• Broader DevOps experience beyond basic Docker usage
• Experience working in small, fast-paced startup teams