Security engineer, application security (UK)

Highlights

• Secure AI agents and LLM architectures powering Fortune 500 brands.
• Build automated AppSec controls that scale across growing AI platform.
• Design security for training data pipelines and customer AI environments.

What they offer

• Generous PTO plus company holidays
• Comprehensive medical and dental insurance
• Paid parental leave for all parents (16 weeks)
• Fertility and family planning support
• Competitive pension scheme with company contribution
• Wellness stipend for gym, massage/chiropractor and personal training
• Learning and development stipend
• Company-wide off-sites and team off-sites
• Company stock options

Ideal candidate

Builder-minded application security engineer who thrives partnering with product teams and enabling developer velocity. You care about securing frontier AI responsibly and owning platform security end to end.

Requirements

• 4+ years of hands-on experience in application security engineering securing large-scale production systems
• Understanding of developer experience and workflows for shipping features while balancing risk and velocity
• Technical expertise in at least two programming languages and ability to review code across multiple languages
• Knowledge of SAST/DAST solutions, vulnerability management, security testing frameworks and DevSecOps practices
• Excellent communication skills translating complex security concepts for technical and non-technical audiences
• Builder's mindset focused on automation, scale and empowerment rather than creating bottlenecks
• Alignment with WRITER values of Connect, Challenge and Own