Freelance Backend Engineer - Fintech Platform & Security

Nsave; Greater London; On-site; GBP 83,000 - 165,000; Part time

Job summary

nsave is a fintech company building scalable backend infrastructure for financial services. The Backend Engineer will own critical subsystems, focusing on architecture, reliability, security, and compliance integrations to serve tens of thousands of users across multiple jurisdictions.

Join a fast-moving fintech environment where product and business context guide technical decisions, balancing speed with quality and security considerations.

Qualifications

• Experience in backend engineering, platform engineering, or infrastructure roles.
• Proficiency in backend languages and frameworks relevant to scalable financial systems.
• Experience in startups, fintech, or regulated environments is strongly preferred.

Responsibilities

• Design, implement, and own critical infrastructure — including service architecture, reliability, build and release, and integration with compliance and banking services
• Proactively improve system health by identifying weak spots in the codebase and infrastructure, and prioritising fixes
• Collaborate with engineering, product, and operations teams to ship features across multiple markets
• Contribute to engineering best practices, code quality, and process improvements as we scale

Skills

Strong engineering fundamentals

Broad platform knowledge

Security-minded

Business-oriented

Tools

CI/CD

Infrastructure as Code

Databases

Job description

nsave is a fintech company building scalable backend infrastructure for financial services. The Backend Engineer will own critical subsystems, focusing on architecture, reliability, security, and compliance integrations to serve tens of thousands of users across multiple jurisdictions.

Join a fast-moving fintech environment where product and business context guide technical decisions, balancing speed with quality and security considerations.