Software Engineer III

Keystone Recruitment is seeking a highly skilled Software Engineer III to design, develop, and scale mobile applications serving millions of users. This role focuses on building high-performance, maintainable mobile software while collaborating with cross-functional teams across the full software development lifecycle.

Responsibilities:

• Design, develop, test, and maintain mobile applications (iOS or Android)
• Build scalable, high-performance features used by millions of active users
• Apply multithreading and memory management best practices
• Contribute to API design and system architecture decisions
• Develop maintainable and testable codebases
• Implement unit testing and automation frameworks
• Improve application performance, reliability, and stability
• Troubleshoot issues and implement system improvements
• Participate in full SDLC: requirements gathering, design, development, testing, and release
• Collaborate with product, QA, and backend teams
• Support production releases and resolve post-launch issues
• Provide mentorship and technical guidance when appropriate

Requirements:

• 2+ years of experience building mobile applications (Android or iOS)
• Experience with multithreading and mobile memory management
• Shipped at least one large-scale product to production supporting millions of users
• Strong experience writing maintainable, testable code
• Experience with API design, unit testing, and automation
• Strong problem-solving and debugging skills
• Solid understanding of software development lifecycle (SDLC)
• Ability to work independently and manage time effectively
• Strong communication and collaboration skills
• Familiarity with system-level software concepts
• Bachelor's degree in Computer Science, Software Engineering, or related field