Hybrid Principal Software Engineer

at Smartnumbers

• Job title: Principal Software Engineer
• Job type: Full Time
• Experience level: Lead
• Salary: £100,000 per year
• Degree requirement: Bachelor's Degree
• Tech skills: AWS, Docker, Microservices, Rust, Go
• Location requirements: Hybrid, London, United Kingdom

About the role

• Principal Software Engineer leading the Platform Group in combating fraud through innovative technology and real-time insights while focusing on team performance and technical direction.

Responsibilities

• Work with the CTO to define and evolve the technical vision and architecture for your team's services.
• Lead technical design decisions with a strong emphasis on resilience, scalability, security, and performance in AWS.
• Promote engineering excellence and modern DevOps practices.
• Partner with Product Managers to refine, prioritise and estimate work, ensuring engineering efforts align strongly with business goals.
• Ensure work flows in a Kanban style, frequently deploying changes whilst triaging and accommodating any issues.
• Optimise ways of working with the team and report on delivery effectiveness.
• Lead, mentor, and support a team of software engineers.
• Conduct 1:1s, performance reviews, and career development conversations.
• Foster a culture of collaboration, ownership, and continuous improvement.
• Actively contribute to the codebase, building and maintaining services/features.
• Guide the team through complex technical challenges and code reviews.

Requirements

• Previous experience as a hands-on Staff or Principal Engineer, ideally within a SaaS technology business serving large enterprise customers.
• Strong capability in AWS and event driven microservices architecture.
• Deep knowledge of object-oriented programming best practices.
• Familiarity with Golang and/or Rust are a bonus.
• Experience with infrastructure-as-code (e.g. CloudFormation, AWS CDK).
• Understanding of CI/CD pipelines and containerisation (e.g. Docker, ECS, Fargate).
• Excellent communication and stakeholder management skills.
• Ability to influence and collaborate effectively across teams and leadership.
• Passion for mentoring and growing engineering talent.
• Background in agile methodologies, particularly Kanban.

Benefits

• Family friendly benefits including paid parental leave policies.
• An extensive health insurance policy for you (option to add family members).
• A workplace pension with Hargreaves Lansdown.
• Life insurance of 4x your salary.
• A discretionary annual bonus of up to 10% of your salary.
• 25 days of annual leave (plus bank holidays), your birthday off, and an opportunity to buy up to 5 days annual leave per year.
• A holistic wellbeing support plan encompassing a variety of offerings to assist you.
• We provide you with a monthly £50 allowance to fund activities to best support your wellbeing as well as workshops and training to provide tools and guidance.
• Additionally, there is a wide-ranging employee assistance programme available to advise on personal, family or financial matters.