Find a job 
Featured Companies 
Featured Universities 
For Companies At a Glance
- Tasks: Lead complex penetration tests across various platforms and mentor junior testers.
- Company: Join Instil, an award-winning tech company with a vibrant culture.
- Benefits: Enjoy flexible working, competitive salary, and extensive health benefits.
- Why this job: Make a real impact in cybersecurity while pushing your technical skills to new heights.
- Qualifications: CHECK Team Lead status and 5+ years of penetration testing experience required.
- Other info: Be part of a supportive community that values growth and innovation.
The predicted salary is between 48000 - 72000 £ per year.
We are looking for a highly skilled Principal Penetration Tester with CHECK Team Lead (CTL) status to join our dynamic security team. This is a senior, hands-on role where you will lead and deliver complex penetration testing engagements across infrastructure, cloud, web, and mobile applications for a diverse range of clients, including software, fintech, manufacturing, engineering, legal, and public sector organisations. You will play a pivotal role in shaping our offensive security services, coordinating end-to-end testing, mentoring junior testers, and contributing to the evolution of our methodologies. If you thrive on tackling challenging security problems, enjoy working in a collaborative environment, and want to keep pushing your technical boundaries, we would love to hear from you.
What You Will Do
- Lead and execute penetration tests across infrastructure, cloud, web, and mobile applications.
- Manage end-to-end engagements: from scoping and kick-off sessions to delivery and client debriefs.
- Produce detailed, actionable reports outlining vulnerabilities and tailored remediation steps.
- Stay ahead of emerging threats by researching new offensive techniques and integrating them into our methodology.
- Automate repetitive tasks and streamline testing processes through scripting.
- Mentor and coach junior testers, supporting their technical growth and career development.
- Enhance tools and methodologies, ensuring our services remain cutting-edge.
- Support pre-sales efforts as a subject-matter expert in penetration testing.
- Communicate findings effectively to both technical and non-technical stakeholders.
- Contribute to thought leadership through blogs, white papers, or speaking engagements.
Essential Skills
- CHECK Team Lead (CTL) status - Infrastructure preferred; Applications also considered.
- Current UK SC Clearance.
- Minimum 5 years penetration testing experience, with a proven track record of complex engagements.
- Proven experience in cloud security reviews (AWS, Azure, GCP).
- Deep expertise in web, mobile, and network penetration testing methodologies.
- Advanced knowledge of operating systems (Linux, Windows, Active Directory).
- Familiarity with cloud environments and ability to perform cloud security reviews.
- Proficiency with tools such as BurpSuite Pro, Nmap, Nessus, Metasploit, and Kali Linux.
- Strong scripting skills (Python, Shell, etc.).
- Excellent communication and technical report writing skills.
Nice-to-Have
- Additional certifications: OSCP, CSTL/CCT, Cyber Scheme, CREST.
- UK Cyber Security Council Chartership (Principal or above).
- Experience with Hack The Box or Capture the Flag simulations.
- Exposure to advanced testing techniques and red team engagements.
Why Join Instil?
At Instil, we believe great work starts with happy, motivated people. That’s why we’ve built a benefits package that supports your wellbeing, growth, and life outside of work, because when you thrive, so do we.
- Recognition That Matters: A discretionary annual performance bonus that rewards your impact and contribution to our success.
- Flexibility Built In: Flexible working arrangements and summer hours, because life isn’t 9 to 5, and balance matters.
- Financial Security: A highly competitive pension scheme with generous employer contributions, private healthcare, and life assurance for peace of mind.
- Health & Wellbeing: Employee Assistance Programme, mental health support, cycle-to-work scheme, and regular social events to keep our culture vibrant.
- Time to Recharge: 35 days holiday, enhanced maternity pay, and family-first policies so you can focus on what matters most.
- Learning Never Stops: From courses to certifications, we’ll invest in your development so you can keep growing and shaping what’s next.
- Community & Culture: Opportunities to volunteer, give back, and be part of initiatives that make Instil a truly inclusive and connected workplace.
And that’s just the start, drop us a note to find out more.
Company Description
Instil has been delivering world-class software engineering and technology solutions for over 20 years, trusted by global brands to solve complex challenges and drive innovation. From modernising legacy systems to building cutting-edge applications, we help our clients navigate an ever-changing digital landscape with confidence and agility. We’re proud to be an award-winning employer, reflecting how our people are at the heart of everything we do: Recognised as a Great Place to Work for three consecutive years, and in 2024 ranked in the Top 20 Best Workplaces in the UK for medium-sized companies. Winner of Company of the Year at the Digital DNA Awards 2022, celebrating excellence in Northern Ireland’s tech sector. Driven by a love for technology and a commitment to excellence, we bring together people who want to make a difference. We’ll support your journey, because your success is part of ours.
Principal Penetration Tester employer: Instil Software
Contact Detail:
Instil Software Recruiting Team
StudySmarter Expert Advice 🤫
We think this is how you could land Principal Penetration Tester
✨Tip Number 1
Network like a pro! Get out there and connect with folks in the industry. Attend meetups, conferences, or even online webinars. You never know who might have the inside scoop on job openings or can refer you directly to hiring managers.
✨Tip Number 2
Show off your skills! Create a portfolio showcasing your penetration testing projects, including any complex engagements you've led. This will not only demonstrate your expertise but also give potential employers a taste of what you can bring to their team.
✨Tip Number 3
Prepare for interviews by brushing up on both technical and soft skills. Be ready to discuss your past experiences in detail, especially those that align with the role. Practice explaining complex concepts in simple terms, as you'll need to communicate effectively with both technical and non-technical stakeholders.
✨Tip Number 4
Don't forget to apply through our website! We love seeing candidates who are genuinely interested in joining our team. Tailor your application to highlight how your skills and experiences align with the Principal Penetration Tester role, and let us know why you're excited about working with us.
We think you need these skills to ace Principal Penetration Tester
Some tips for your application 🫡
Tailor Your CV: Make sure your CV reflects the skills and experiences that match the Principal Penetration Tester role. Highlight your CHECK Team Lead status, relevant certifications, and any specific projects that showcase your expertise in penetration testing.
Craft a Compelling Cover Letter: Use your cover letter to tell us why you're the perfect fit for our team. Share your passion for tackling security challenges and how your experience aligns with our mission at Instil. Don't forget to mention your mentoring experience!
Showcase Your Technical Skills: In your application, be sure to highlight your proficiency with tools like BurpSuite Pro and Metasploit, as well as your scripting skills. We want to see how you stay ahead of emerging threats and contribute to evolving methodologies.
Apply Through Our Website: We encourage you to apply directly through our website for a smoother process. This way, we can easily track your application and ensure it gets the attention it deserves. Plus, it shows you're keen on joining our dynamic team!
How to prepare for a job interview at Instil Software
✨Know Your Stuff
Make sure you brush up on your penetration testing methodologies, especially those related to infrastructure, cloud, web, and mobile applications. Be ready to discuss specific tools like BurpSuite Pro and Metasploit, and how you've used them in past engagements.
✨Showcase Your Leadership Skills
As a Principal Penetration Tester, you'll be expected to lead and mentor junior testers. Prepare examples of how you've successfully managed teams or projects in the past, and be ready to discuss your approach to coaching others.
✨Communicate Clearly
You'll need to convey complex technical findings to both technical and non-technical stakeholders. Practice explaining your past projects and their outcomes in simple terms, focusing on the impact of your work and the actionable steps you provided.
✨Stay Ahead of the Game
Research the latest trends and emerging threats in cybersecurity. Be prepared to discuss how you stay updated and how you’ve integrated new offensive techniques into your previous work. This shows your commitment to continuous learning and innovation.