Software Engineer, iOS - Securing Engineering, USDS

TikTok USDS Joint Venture; San Jose (CA); On-site; USD 187,000 - 360,000; Full time

Job summary

TikTok USDS Joint Venture LLC is seeking a Software Engineer to lead the design and development of AppGuard for Apple platforms, focusing on monitoring and managing egress/ingress traffic on iOS and macOS. You will be a key contributor in a greenfield environment, applying high-performance engines and DSL to ensure application assurance.

The role requires 3+ years in Apple platform development, strong Objective-C/Swift expertise, and a track record of memory, network, and battery optimization.

Qualifications

• BS/MS degree in Computer Science, Engineering, or a related field.
• 3+ years of experience in mobile and desktop app development for Apple platforms.
• Expertise in Objective-C and Swift, with a deep understanding of Darwin-based frameworks and system-level tools.
• Performance Optimization: Proven experience with memory management, network optimization, and battery efficiency.

Responsibilities

• Architect Security Solutions: Take ownership of the technical direction for AppGuard, from initial design to implementation on iOS and macOS.
• Traffic & Policy Control: Develop capabilities to monitor and cut-off application traffic based on dynamic rule updates and sampling
• Performance Engineering: Implement high-performance engines to execute DSL-based logic for real-time security judging.
• Tooling Development: Design and develop associated platforms for the integration, testing, validation, and profiling of sandbox components.
• Collaborate Cross-Functionally: Work with stakeholders to ensure security solutions meet operational needs without compromising user experience.

Skills

Objective-C

Swift

Security engineering

Performance optimization

Education

BS/MS degree in Computer Science, Engineering, or a related field.

Job description

Responsibilities

About the team

The Security Engineering team is missioned to run and operate security infrastructures, platforms and technologies, as well as to support cross-functional teams to protect our users, products and infrastructures. This team is responsible for enhancing security tools and identifying vulnerabilities, with a specific focus on content assurance and the application of large language models (LLMs). You'll collaborate cross-functionally with partners inside and outside TikTok to fortify our products and users' security, helping to establish TikTok as the most trusted platform.

Responsibilities

We are seeking a Software Engineer to be a core member of our Apple Platforms team. In this role, you will lead the design and development of an AppGuard security framework, specifically focusing on the monitoring and management of all egress/ingress traffic. You will be a key contributor in a greenfield environment, applying high-performance engines and Domain-Specific Languages (DSL) to ensure application assurance.

• Architect Security Solutions: Take ownership of the technical direction for AppGuard, from initial design to implementation on iOS and macOS.
• Traffic & Policy Control: Develop capabilities to monitor and cut-off application traffic based on dynamic rule updates and sampling
• Performance Engineering: Implement high-performance engines to execute DSL-based logic for real-time security judging.
• Tooling Development: Design and develop associated platforms for the integration, testing, validation, and profiling of sandbox components.
• Collaborate Cross-Functionally: Work with stakeholders to ensure security solutions meet operational needs without compromising user experience.

Qualifications

Minimum Qualifications

• BS/MS degree in Computer Science, Engineering, or a related field.
• 3+ years of experience in mobile and desktop app development for Apple platforms.
• Expertise in Objective-C and Swift, with a deep understanding of Darwin-based frameworks and system-level tools.
• Performance Optimization: Proven experience with memory management, network optimization, and battery efficiency.

Preferred Qualifications

• Hands-on experience with Network Extensions or system-level traffic filtering.
• Demonstrated ability to contribute to architectural design and translate business security goals into technical vision.
• Familiarity with AI-enabled development tools (e.g., Cursor, Replit) to accelerate core logic implementation.

About USDS

TikTok USDS Joint Venture LLC is dedicated to the safety and security of millions of Americans who create, discover, and connect with what they love on the apps we operate. The Joint Venture has been established in compliance with the Executive Order signed by President Trump on September 25, 2025. Our foundation is a comprehensive data privacy and cybersecurity program we operate under defined safeguards to protect national security and secure U.S. user data, apps and the algorithm. We safeguard the U.S. content ecosystem, holding decision‑making authority for trust and safety policies and moderation. USDS Joint Venture helps ensure Americans can continue to express their creativity, discover new hobbies and interests, and build thriving communities and businesses on a global scale.

On-site presence across teams allows the company to operate with greater speed, alignment, and agility — especially in areas like real-time decision-making, team development, and integrated execution. As such, the company is shifting from a hybrid work model to a fully in-person schedule up to 5 days a week.

Why Join Us

Inspiring creativity is at the core of TikTok's mission. Our innovative product is built to help people authentically express themselves, discover and connect – and our global, diverse teams make that possible. Together, we create value for our communities, inspire creativity and bring joy - a mission we work towards every day.

We strive to do great things with great people. We lead with curiosity, humility, and a desire to make impact in a rapidly growing tech company. Every challenge is an opportunity to learn and innovate as one team. We're resilient and embrace challenges as they come. By constantly iterating and fostering an "Always Day 1" mindset, we achieve meaningful breakthroughs for ourselves, our company, and our users. When we create and grow together, the possibilities are limitless. Join us.

Diversity & Inclusion

TikTok is committed to creating an inclusive space where employees are valued for their skills, experiences, and unique perspectives. Our platform connects people from across the globe and so does our workplace. At TikTok, our mission is to inspire creativity and bring joy. To achieve that goal, we are committed to celebrating our diverse voices and to creating an environment that reflects the many communities we reach. We are passionate about this and hope you are too.

USDS Reasonable Accommodation

USDS is committed to providing reasonable accommodations in our recruitment processes for candidates with disabilities, pregnancy, sincerely held religious beliefs or other reasons protected by applicable laws. If you need assistance or a reasonable accommodation, please reach out to us at https://tinyurl.com/USDS-RA

Job Information

【For Pay Transparency】Compensation Description (Annually)

The base salary range for this position in the selected city is $187040 - $359720 annually.

Compensation may vary outside of this range depending on a number of factors, including a candidate’s qualifications, skills, competencies and experience, and location. Base pay is one part of the Total Package that is provided to compensate and recognize employees for their work, and this role may be eligible for additional discretionary bonuses/incentives, and restricted stock units.

Benefits may vary depending on the nature of employment and the country work location. Employees have day one access to medical, dental, and vision insurance, a 401(k) savings plan with company match, paid parental leave, short-term and long-term disability coverage, life insurance, wellbeing benefits, among others. Employees also receive 10 paid holidays per year, 10 paid sick days per year and 17 days of Paid Personal Time (prorated upon hire with increasing accruals by tenure).

The Company reserves the right to modify or change these benefits programs at any time, with or without notice.

For Los Angeles County (unincorporated) Candidates:

1. Interacting and occasionally having unsupervised contact with internal/external clients and/or colleagues;
2. Appropriately handling and managing confidential information including proprietary and trade secret information and access to information technology systems;
3. Exercising sound judgment.