Principal Security Engineer

About Linkly

Linkly is a PE-backed, Australian fintech focusing on payment integration solutions. We are a leading provider in ecommerce recurring billing, and our middleware powers over 200,000 terminals and processes over two billion transactions annually. Our applications support over 800 integrations into POS solutions. We have built our reputation through seamless integration of payment terminals and POS systems and are continuing to innovate in creating a terminal and acquirer independent payment solicitor for in-store. Our clients include major banks and retailers such as Woolworths, David Jones, JB Hi-Fi, and Bunnings.   

Our goal is to continuously lead the payments industry with new technology delivering value to clients, which who include merchants, banks, acquirers and POS vendors, expanding our presence into other regions. 

About the Role

We’re looking for a Principal Security Engineer to join our team and take ownership of building Linkly’s internal penetration testing capability and lead threat modelling across our product portfolio alongside our Chief Security Officer. 

This role requires deep technical cloud security expertise, with Azure as our primary platform. You’ll work to help validate that the design and configuration of our products and services meet security requirements. Engineering owns the design; you make sure it holds up. 

As a principal individual contributor, you’ll also share your expertise with the team, mentoring other engineers, including senior engineers, and helping lift security capability across the business. 

Our Security team is small, which means your work won’t be limited to penetration testing or threat modelling. You’ll have the opportunity to get involved across various stages of how we secure our products and services, from early design through to ongoing operation.

This is a hybrid role working 3 days in our Sydney office.

Key Responsibilities

• Build and run Linkly’s internal penetration testing function, defining its strategy and approach and carrying out testing across our cloud infrastructure, products and services. 

• Carry out security assessments of new changes to our cloud infrastructure. 

• Consult with engineering teams and validate and test that the design and configuration of their products and services are secure and meet security requirements. 

• Own Linkly’s security guidelines and define the security baselines our cloud environments are built and measured against. 

• Provide security design review and testing for upcoming initiatives, including our new data product. 

• Mentor other engineers in the Security team, including senior engineers, sharing your knowledge and experience. 
  
  

What You'll Need

• 10+ years’ experience as a security engineer, penetration tester or security consultant, operating at a senior level. 

• Extensive hands-on penetration testing experience, including experience establishing and leading a penetration testing capability. 

• Expert, detailed technical knowledge of Microsoft Azure, including cloud-native attack techniques and common misconfigurations. 

• Proven experience with secure cloud architecture, particularly on Azure. 

• Proven experience developing threat models and helping engineering teams reason through different ways to reduce security risk. 

• Strong scripting or programming skills (e.g. Python or PowerShell) to automate testing and build your own tooling. 

• Ability to write clear, concise reports covering findings, risks and practical remediation recommendations. 

• Strong communication skills, with the ability to explain technical security concepts to both technical and non-technical audiences. 

• Experience mentoring other engineers. 
  
  

Nice to Have

• AWS experience, including secure cloud architecture on AWS. 

• Certified Ethical Hacker (CEH) or an equivalent certification. 

• Exposure to PCI DSS and the payments industry. 

Our Values

• Act Like an Owner: Take full accountability for outcomes and make decisions with the long-term success of Linkly in mind.
• Innovate: Challenge assumptions, champion new ideas and drive meaningful change for customers and the business.
• Deepen Trust: Build confidence through integrity, transparency and consistent delivery with your team, partners and clients.
• Care and Respect: Foster an inclusive, supportive environment where everyone feels valued and empowered to do their best work.