SaaS Technical Architect

Senior Software Engineer
London (Hybrid – 1 day per week in office)
£70,000–£100,000 + Benefits
 
Certus Recruitment is partnering with an innovative fintech business operating at the intersection of financial services, digital assets, and modern software engineering. As they continue to build a highly regulated next-generation payments platform, they are seeking two Senior Software Engineers to join their growing engineering team.
 
This is a unique opportunity to work on complex, mission-critical systems where correctness, security, and scalability are non-negotiable. Successful candidates will play a key role in designing, building, and delivering the services, applications, and core platforms that underpin a regulated financial ecosystem.
 
Working closely with senior technical leadership, you'll take ownership of features from concept through to production, building robust systems that process transactions, enforce compliance controls, maintain accurate financial records, and integrate with modern blockchain technologies.
 
Key Responsibilities

• Design, develop, and maintain backend services and APIs
• Build and enhance high-integrity transaction, settlement, and ledger systems
• Deliver features across the full software lifecycle, from design through deployment
• Contribute to customer-facing applications and internal operational tooling
• Collaborate on smart contract integrations and blockchain-based workflows
• Ensure systems are scalable, secure, auditable, and production-ready
• Produce clear technical documentation and contribute to architecture discussions
• Work within a design-led engineering culture focused on quality and long-term maintainability

Required Experience

• 5+ years of professional software engineering experience
• Strong experience building and operating production-grade software systems
• Background in environments where accuracy and reliability are critical, such as fintech, payments, banking, financial services, or other highly regulated sectors
• Commercial experience with TypeScript and modern backend development
• Strong SQL and database design skills, ideally PostgreSQL
• Experience taking products or platforms from early-stage development through to production
• Excellent written communication and documentation skills
• Ability to work collaboratively within a highly technical, engineering-led environment

Desirable Experience

• Exposure to Rust or an interest in developing expertise in systems programming
• Experience with React, modern frontend frameworks, and full-stack development
• Understanding of blockchain technologies, digital assets, or cryptographic systems
• Familiarity with event-driven architectures, distributed systems, or financial ledgers
• Experience working within regulated industries

This role offers the opportunity to work on genuinely challenging engineering problems while helping shape the future of regulated digital finance. Candidates will join a highly capable team where engineering quality, technical ownership, and thoughtful system design are valued and rewarded.

For a confidential discussion and full details, contact Certus Recruitment today.
 
Certus Recruitment is a well-established and experienced specialist consultancy providing GTM and Technical recruitment services. We serve the technology sector across the UK, Europe, North America, and Australia.