What you'll do:

We are seeking a highly skilled and experienced engineer specializing in Flutter to join our Mobile Engineering Team. As a Sr. Mobile Engineer I, you will lead mobile architecture, mentor engineers, and deliver scalable, high-performance applications that power a seamless cross-platform experience. You will influence technical direction across teams, set a high standard for engineering excellence, and drive end-to-end quality and reliability in our mobile products.

In this role you will:

• Own the life cycle of features through debugging, documenting, testing, releasing, and monitoring
• Take part in daily stand-ups and regular team-wide meetings to discuss current and upcoming tasks
• Participate in the technical roadmap for mobile architecture, frameworks, and tooling
• Participate in design reviews, architecture discussions, and performance optimization efforts across iOS and Android
• Implement robust, maintainable Flutter solutions that follow best practices for state management, dependency injection, and reactive programming
• Collaborate with Product and Design teams to iteratively improve the user experience on mobile platforms
• Investigate issues, mitigate them, and recommend preventative measures
• Improve observability, monitoring, and crash analytics to ensure product stability and quality
• Help foster a culture of technical excellence, innovation, and collaboration

What you'll need:

• 6+ years of professional software engineering experience
• 2+ years of hands-on Flutter and Dart experience in production environments
• Understanding of mobile architecture, state management, and design patterns (e.g., BLoC, MVVM, Clean Architecture)
• Experience maintaining testing strategies for Flutter applications, spanning unit, widget, integration, and end-to-end levels
• Familiarity with building CI/CD automation for mobile delivery
• Understanding of RESTful APIs, WebSockets, and offline data handling
• Familiarity with optimizing performance, reliability, and user experience across diverse devices
• Ability to perform in a team environment adopting agile principles
• Strong written and verbal communication skills
• Strong grasp of OOP design principles

Bonus Points for:

• Knowledge of native iOS (Swift) and Android (Kotlin/Java) integration
• Experience with fintech or trading platforms
• Contributions to open-source frameworks or SDKs

Compensation:

The salary range for this role will be $125,000.00 - $175,000.00 USD. In addition, this position will also receive an annual target bonus of 12%. Bonus pay at NinjaTrader is based on individual performance (50%) as well as company/team performance (50%).

Salary and bonus earnings are only two components of the total compensation package offered by NinjaTrader. NinjaTrader offers a 401K plan through ADP under which the company will match up to 3.5% of employee contributions. Annual paid time off allowance accrues at a rate of 18 days per year (some positions may qualify for more) plus seven paid holidays.

Location:

This role is based in Chicago, IL. *There may be remote flexibility for exceptional candidates in the following states: California, Colorado, Florida, Georgia, Illinois, Indiana, Minnesota, Missouri, Montana, New Jersey, New York, North Carolina, Ohio, Oregon, Pennsylvania, South Carolina, Texas, Utah, Vermont, Virginia, Washington, Washington DC, Wisconsin.

Hybrid:

For Chicago-based employees, we follow a hybrid work schedule: In-office Tuesday through Thursday, with remote work on Mondays and Fridays. In addition to these weekly remote days, we offer:

• 20 additional flex remote days annually
• 5 Company Wide Office-Optional weeks tied to major holidays