Application Guide

How to Apply for Senior Hardware Security Engineer

at Lime

🏢 About Lime

Lime is a leader in micro-mobility, providing eco-friendly shared scooters and bikes in cities worldwide. Working here means contributing to sustainable urban transportation while tackling unique hardware security challenges in a fast-paced, IoT-heavy environment.

About This Role

As Senior Hardware Security Engineer, you'll protect Lime's fleet of connected vehicles from physical and firmware attacks. Your work ensures rider safety, prevents tampering, and maintains the integrity of Lime's hardware platforms at scale.

💡 A Day in the Life

Start by reviewing threat models for a new scooter component, then run side-channel analysis on a firmware update. After lunch, collaborate with hardware engineers to implement a secure boot fix, and end the day by scripting an automated test for flash memory integrity.

🎯 Who Lime Is Looking For

  • 5+ years in hardware/firmware security, with proven experience in side-channel analysis, fault injection, and firmware reverse engineering.
  • Deep understanding of embedded systems security, including secure boot, trusted execution environments, and hardware root of trust.
  • Hands-on proficiency with lab equipment like oscilloscopes, logic analyzers, and fault injection tools (e.g., ChipWhisperer, GlitchKit).
  • Strong communication skills to present security findings to cross-functional teams and influence hardware design decisions.

📝 Tips for Applying to Lime

1

Highlight specific projects where you performed side-channel analysis or fault injection on embedded devices—mention tools and outcomes.

2

Tailor your resume to show experience with IoT or transportation hardware, as Lime's fleet is a unique attack surface.

3

Include examples of automated security tooling you've built (e.g., Python scripts for firmware analysis or fuzzing).

4

Demonstrate knowledge of Lime's products—mention their scooters' connectivity features (GPS, cellular, Bluetooth) in your cover letter.

5

Prepare to discuss how you'd approach threat modeling for a distributed fleet of shared vehicles.

✉️ What to Emphasize in Your Cover Letter

['Emphasize your hands-on experience with physical attack methodologies and lab equipment.', "Show how your work directly impacts product security and user safety, aligning with Lime's mission.", 'Mention experience building automated security pipelines for firmware analysis.', 'Express enthusiasm for the micro-mobility industry and the unique security challenges of connected vehicles.']

Generate Cover Letter →

🔍 Research Before Applying

To stand out, make sure you've researched:

  • Read Lime's engineering blog or tech talks for insights into their hardware stack.
  • Understand Lime's fleet management system and how connectivity (cellular, BLE) could introduce attack vectors.
  • Review recent research on IoT scooter vulnerabilities (e.g., from Defcon or academic papers).
  • Familiarize yourself with Lime's public security policies or bug bounty program if available.

💬 Prepare for These Interview Topics

Based on this role, you may be asked about:

1 Describe a time you discovered a critical hardware vulnerability—how did you exploit and report it?
2 How would you design a secure boot chain for a resource-constrained IoT device?
3 Walk through your approach to side-channel analysis on an ARM Cortex-M target.
4 What automated tools have you built for firmware reverse engineering?
5 How do you prioritize security findings when working with hardware manufacturing timelines?
Practice Interview Questions →

⚠️ Common Mistakes to Avoid

  • Avoid being too theoretical—Lime needs hands-on engineers who can use oscilloscopes and soldering irons.
  • Don't ignore the physical aspect: emphasize lab work, not just software security.
  • Don't overlook the company's mission—show genuine interest in sustainable transportation, not just the tech.

📅 Application Timeline

This position is open until filled. However, we recommend applying as soon as possible as roles at mission-driven organizations tend to fill quickly.

Typical hiring timeline:

1

Application Review

1-2 weeks

2

Initial Screening

Phone call or written assessment

3

Interviews

1-2 rounds, usually virtual

Offer

Congratulations!

Ready to Apply?

Good luck with your application to Lime!