Senior Mobile Engineer (Objective-C / Cocos - Live Game Evolution)

UserWise; Poland; On-site; PLN 217,391 - 326,087; Full time

Benefits offered by this job

Market competitive, tax-free USD salaries

Paid Time Off

Performance Bonus

Annual Performance Reviews

Job summary

UserWise in Poland is looking for an experienced developer to maintain and enhance a high-performing mobile game built with Objective-C and Cocos. The role focuses on optimizing performance, refactoring legacy systems, and utilizing AI-assisted workflows to accelerate development. Ideal candidates should have strong experience with iOS development and a pragmatic approach to improving codebases. Competitive tax-free USD salaries, paid time off, and performance bonuses are offered.

Qualifications

• Strong experience with Objective-C and iOS development.
• Hands-on experience with Cocos (Cocos2d-x or similar).
• Experience working on live mobile games or shipped apps.

Responsibilities

• Maintain and extend a legacy Objective-C + Cocos codebase.
• Optimize performance, memory usage, and runtime behavior for mobile.
• Collaborate closely with product, design, and analytics to drive impact.

Skills

Objective-C

iOS development

Cocos

performance optimization

legacy codebases

AI tools

Job description

About Us

At UserWise Services, we build and scale mobile games played by millions worldwide. Our focus is simple: move fast, deliver impact, and use modern tools—including AI-assisted workflows—to accelerate development and iteration.

The Role

You'll work on a proven, high-performing mobile game built with Objective-C and Cocos, helping evolve it for the next stage of growth. This is not a "build from scratch" role—it's about:

• Improving a live product with real users
• Making smart, high-leverage technical decisions
• Using AI tools to accelerate development, debugging, and refactoring

Why This Role Is Interesting

• Work on a game that already has traction and players
• See your impact immediately in a live environment
• Use AI as a force multiplier, not just a buzzword
• Solve real engineering problems—not just greenfield abstractions

Who This Is For

• Engineers who enjoy fixing, improving, and evolving real products
• People who like high ownership and fast execution
• Builders who prefer impact over perfection

What You'll Do

• Maintain and extend a legacy Objective-C + Cocos codebase
• Optimize performance, memory usage, and runtime behavior for mobile
• Refactor and modernize systems without breaking live operations
• Ship features, events, and improvements in a live-service environment
• Use AI-assisted workflows (code generation, debugging, refactoring, test creation) to move faster
• Collaborate closely with product, design, and analytics to drive impact
• Identify quick wins vs. deep tech improvements and prioritize accordingly

What We're Looking For

• Strong experience with Objective-C and iOS development
• Hands-on experience with Cocos (Cocos2d-x or similar)
• Experience working on live mobile games or shipped apps
• Ability to navigate and improve legacy codebases
• Strong understanding of performance optimization (CPU, memory, rendering)
• Pragmatic mindset: you know when to refactor vs. ship
• Comfortable leveraging AI tools (e.g., Copilot, ChatGPT, etc.) as part of your workflow

Nice to Have

• Experience with C++ (common in Cocos-based systems)
• Familiarity with game loops, rendering pipelines, and animation systems
• Experience migrating legacy systems to modern architectures
• Exposure to analytics-driven development (A/B testing, live ops)

Benefits

• Market competitive, tax-free USD salaries
• Paid Time Off
• Performance Bonus
• Annual Performance Reviews