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Application Security Engineer

LorienLondon🇬🇧United KingdomPosted 2 Sept 2026

Quick Overview

Seniority
Mid Senior
Employment type
Temporary/Casual
Work mode
Hybrid
Location
London, United Kingdom
AWSMFAOWASPSAMLGitHub ActionsKubernetesPythonTerraform

Job Description

Application Security Engineer Location: London (Hybrid) Contract: Inside IR35

We're looking for a hands-on Application Security Engineer to join a growing cyber engineering team. You'll play a key role in vulnerability remediation, security incident response, identity and secrets management, and security automation across cloud and application environments.

Key Responsibilities

  • Manage the end-to-end HackerOne life cycle, from triage to remediation and closure.
  • Support security incident investigations and implement effective fixes.
  • Provide guidance on Okta and Doppler integrations and best practices.
  • Design and build security automation to improve scale and efficiency.
  • Partner with the Director of Cybersecurity on AppSec, DevSecOps, and cloud security initiatives.

Required Experience

  • Hands-on experience with HackerOne or similar bug bounty platforms.
  • Strong web application security knowledge (OWASP Top 10, ASVS, threat modelling).
  • Experience building security tooling and automation.
  • Familiarity with security testing tools such as Burp Suite.
  • Exposure to incident response and application security.
  • Strong communication and stakeholder engagement skills.

Desirable Skills

  • Python Scripting.
  • SAST, DAST, SCA, and secrets-scanning tools.
  • GitHub Actions, Terraform, Kubernetes, and IAM security.
  • Okta (OIDC, SAML, MFA) and Doppler experience.
  • AWS Cloud Security expertise.

Guidant, Carbon60, Lorien & SRG - The Impellam Group Portfolio are acting as an Employment Business in relation to this vacancy.

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