Mobile Security System Engineer

We are building a real-time mobile data firewall designed to prevent sensitive information from leaving the device. Our product focuses on:

• Real-time monitoring of conversation content on the device

• Detecting risks such as self-harm, violence, harassment, data leakage, and AI misuse

• Intercepting, blocking, or alerting users before data is sent out

• Preventing sensitive information from being transmitted to cloud services, AI models, or messaging apps

We are looking for a system-level security engineer who can rapidly build and iterate on an MVP in a fast-moving environment.

• Hands-on system-level development experience on either Android or iOS

• Experience in at least one of the following areas:

– Real-time traffic processing

– Device-level data monitoring

– Real-time blocking or interception

• Strong understanding of networking fundamentals (TCP, UDP, HTTPS, TLS)

• Ability to independently handle:

– Persistent background execution

– High-performance real-time processing

– Data encryption and privacy protection

• Strong problem-solving, debugging, and testing capabilities

• Ability to collaborate effectively with backend, product, AI, and QA teams

What You Will Do

• Design and develop real-time on-device data monitoring and interception mechanisms for Android / iOS

• Implement real-time capabilities on the device, including:

– Sensitive content detection

– Risk classification (self-harm, violence, harassment, data leakage)

– Pre-send blocking, alerting, or delaying actions

• Support coverage across messaging apps, AI applications, browsers, and WebView

• Solve mobile-security-related challenges such as:

– Persistent background execution

– Avoiding system process termination

– Balancing high performance with low power consumption

• Collaborate directly with AI and backend teams to rapidly validate risk control effectiveness

Core Responsibilities

1. Design and implement on-device security features for Android / iOS, including:
2. – Real-time data protection, interception, and behavior monitoring
3. – Integration of application-layer and system-layer security mechanisms
4. Research mobile OS security architectures and evaluate vulnerabilities or attack surfaces across different OS versions
5. Develop and optimize security detection modules such as:
6. – Malicious behavior detection
7. – Jailbreak / Root detection
8. – Anti-tampering and anti-reverse-engineering protections
9. Work cross-functionally with backend engineers, product managers, and AI teams to integrate a unified security workflow
10. Prepare technical documentation, track emerging trends in mobile security, and propose continuous improvements

臺北市Taipei City