Web Security Engineer JavaScript

Client Server; Greater London; Hybrid; GBP 72,000 - 88,000; Full time

Benefits offered by this job

Bonus

Equity

Job summary

Client Server is seeking a Web Security Engineer to collaborate with the web development team and dominate offensive security across web-based applications. You will perform penetration testing, reverse engineering and vulnerability assessments, identifying risks and guiding developers to build secure, resilient software from the ground up.

You can work from home most of the time, with London office meetups about twice a month for innovation sessions and team meetings.

Qualifications

• Strong experience in web application security and offensive security testing.
• Hands-on expertise in penetration testing and reverse engineering.
• Deep understanding of modern web security vulnerabilities and mitigation techniques.
• Comfortable writing and reviewing production code, not just identifying vulnerabilities.
• Collaborative and pragmatic, able to work closely with engineering teams.

Responsibilities

• Perform penetration testing, reverse engineering and vulnerability assessments to identify security risks.
• Collaborate with the web development team to ensure security is at the centre of web applications.
• Bridge between Security and Engineering to embed secure coding throughout the SDLC.
• Guide architecture and design decisions with expert security input.

Skills

Web application security

Offensive security testing

Penetration testing

Reverse engineering

Secure coding practices

Job description

You could be progressing your career at a global leader in Computer Vision, AI and biometric identity, whose technology protects governments, critical infrastructure and some of the world's largest enterprises against identity fraud, deepfakes and sophisticated cyber threats.

As a Web Security Engineer you'll collaborate closely with the web development team to ensure security is at the centre of all web based applications. Joining a specialist security team, you'll focus on offensive web security, acting as the bridge between Security and Engineering. You'll perform penetration testing, reverse engineering and vulnerability assessments, identifying security risks and working closely with developers to build secure, resilient web applications from the ground up.

This is a highly collaborative role where you'll provide expert guidance on secure coding practices, influence architecture and design decisions and help embed security throughout the software development lifecycle.

Location / WFH:

You can work from home most of the time, meeting up with colleagues in the London office approximately twice a month for innovation sessions and team meetings.

About you:

• You have strong experience in web application security and offensive security testing
• You have hands‑on expertise in penetration testing and reverse engineering
• You have a deep understanding of modern web security vulnerabilities and mitigation techniques
• You're comfortable writing and reviewing production code, not just identifying vulnerabilities
• You're collaborative and pragmatic, able to work closely with engineering teams

What's in it for You?

• Salary to £80k
• Bonus
• Equity
• Excellent career progression