Senior AppSec Engineer
Department: Consultancy
Employment Type: Full Time
Location: Remote
Description
The Role
Are you passionate about building security into software from the ground up? We’re looking for a Senior Application Security Engineer to take charge of strengthening and evolving security across our Loyalty division.
In this role, you won’t just identify risks you’ll lead the charge in transforming how secure software is built, working side-by-side with engineering and product teams to make security an intrinsic part of everything we deliver.
What you’ll be doing
Own and drive application security strategy, influencing key security metrics and outcomes
Embed secure-by-design principles into every stage of the development lifecycle
Partner with engineers and product teams to elevate security awareness and capability
Introduce and optimise automated security controls within CI/CD pipelines
Lead threat modelling and secure design discussions, shaping decisions around critical areas like authentication and data protection
Ensure security tooling (SAST, DAST, SCA) is effective, scalable, and delivering real value
Oversee and enhance testing initiatives including penetration testing, scanning, and bug bounty programmes
Act as a trusted advisor to engineering teams triaging issues and guiding practical remediation
Contribute to security standards, documentation, and audit readiness
Champion a strong, proactive security culture across the organisation
Knowledge Skills & Abilities
A background in software engineering with a security-first mindset
Strong knowledge of modern web and API vulnerabilities (OWASP Top 10 and beyond)
Hands-on experience with automation, scripting, and integrating security into CI/CD workflows
Familiarity with security tooling such as SAST, DAST, and SCA
Experience working in cloud-native environments (AWS), microservices, and containerised systems
Confidence in reviewing architecture, leading threat modelling, and influencing secure design decisions
Excellent communication skills, ablility to engage, educate, and inspire engineering teams
Behaviours
An open and genuine communicator
Able to take responsibility for your actions
Always learning and wanting to improve
Takes responsibility for own development
Love what you do
Value and support your team
Embrace who you are
Open minded and willing to explore new ideas
What We Offer
We value our team and to attract exceptional people, we offer an excellent package! In 2023, 2024 and 2025 we were recognised as one of the Best Workplaces in Tech by Great Place To Work UK, the global authority on workplace culture.
As a Leighton employee you can look forward to:
A competitive salary this will be dependent on experience.
A contributory pension scheme
Private healthcare
25 days annual leave, plus bank holidays and the opportunity to buy or sell holiday
A flexible approach to working hours
Continuous personal development, career path and training
And more....