Senior Software Engineer - Android Systems & Security

Team: Core Engineering

Location: San Francisco, CA

Commitment: Full-Time

Workplace Type: hybrid

Salary:

Responsibilities

Framework Engineering: Develop and maintain custom modifications within the Android Framework (AOSP) and Hardware Abstraction Layers (HAL).

OEM Integration: Partner with global smartphone manufacturers and chipset vendors to integrate PayJoy’s proprietary technology into factory firmware.

Cross-Border Collaboration: Work daily with our China-based engineering team to align on technical specifications and manufacturing requirements.

Feature Development: Implement new locking features that interact with system-level services for example Telephony, Power Management, and Device Policy Manager, etc…

R&D & Debugging: Use deep chip-level knowledge to troubleshoot integration issues across different silicon providers (Qualcomm, MediaTek, etc.).

Process Automation: Contribute to OTA (Over-the-Air) updates and global device testing.

Requirements

• Android Internals Expertise: Extensive, hands-on experience with AOSP development, including modifying system services and utilizing the Android build system (Soong/Make).

• Low-Level Language Mastery: Expert-level proficiency in Java and C/C++ (JNI). (Ability to read/write Kotlin is expected, but core work remains at the system level).

• OEM/Firmware Background: Proven experience working with or for an OEM or chipset vendor on firmware customization, device bring-up, or security hardening.

• Strong Core Skills: Demonstrable knowledge of AOSP and TEE / ARM TrustZone.

• ⚠️ Note: If your background is primarily focused on building consumer-facing commercial apps (e.g., banking, gaming, or general retail apps), this role will not be a match for your skillset.

🌟 Desirable Skills (Pluses):

• Experience with Secure Boot, verified boot (AVB), and common Android exploit vectors.

• Automation of firmware build pipelines and signing processes using Python or Bash.

• Comfort collaborating effectively with international teams across different time zones.

💬 Ready to solve complex engineering challenges that almost no one else in the industry is tackling? Apply directly or send me a DM. Lets chat!

Benefits

• Local benefits depending on the country of hire
• Company-funded health insurance for employee and immediate family
• Company-funded employee life and disability insurance
• Paid vacation days, unlimited sick leave
• $2,000 USD annual Co-working travel perk
• $2,000 USD annual Professional Development perk
• Phone finance, headphone benefit, home office equipment allowance and wellness perks 
• Catered lunches