We are seeking an experienced Security Solution Designer with strong application and network architecture expertise to shape secure, resilient solutions within a regulated financial services environment. This role combines application architecture leadership with network security and segmentation design, requiring someone who can confidently operate across both disciplines. This is a must-have role for candidates with a software development background first, who deeply understand application architecture, and can also design the network and security controls required to protect those applications. The role is inside IR35 with a requirement to be in the Sheffield office up to 3-days per week. The role You will own end-to-end security solution design, producing high-quality architecture artefacts aligned to enterprise standards, regulatory expectations, and security frameworks (eg NIST). You will work closely with CTO and network engineering teams, regulatory stakeholders, and delivery teams to ensure solutions are secure, compliant, and fit for purpose. This role operates at the intersection of application architecture and network architecture, requiring strong communication, documentation, and stakeholder engagement skills. Essential experience (must have): Strong application architecture experience: o Designing modern software systems using recognised architecture patterns o Defining application standards, patterns, and design principles o API design and system integration