Senior Backend Engineer at Duplo

Responsibilities

Backend Development:

• Design, develop, and maintain scalable, reliable backend systems using TypeScript and NestJS, with a focus on correctness in financial systems
• Design robust service boundaries and maintainable architecture across distributed services
• Architect and optimize PostgreSQL schemas for scale, including transaction handling, indexing strategy, and patterns that protect data correctness
• Apply Redis effectively for caching, coordination, rate-limiting, and distributed locking.

Cloud Infrastructure:

• Reason effectively about deployment safety, observability, scaling, and incident diagnosis in production environments running on Docker, Kubernetes, and AWS
• Maintain strong operational understanding of configuration and secrets handling, runtime behaviour, and rollback strategy
• Work closely with DevOps to ensure infrastructure decisions support reliability; treating infrastructure as a shared concern.

Technical Leadership:

• Champion technical design and implementation for large, high-risk, or high-complexity initiatives
• Break down complex technical requirements into manageable, well-sequenced work
• Mentor and guide junior engineers, raising engineering standards through example
• Make sound, well-reasoned decisions on architectural trade-offs, migration approaches, and rollout safety, and know when to escalate decisions with broader business impact.

Quality & Risk Ownership:

• Understand edge cases in money movement and design with operational safety and compliance in mind, not just functional correctness
• Drive thorough testing practices to ensure robust, reliable code before it reaches production
• Take responsibility for overall outcomes, not just tasks.

Collaboration:

• Work seamlessly with cross-functional partners  including product, compliance, finance, operations, support, QA, DevOps, and external providers, communicating clearly and adapting your approach to whoever you are working with
• Collaborate closely with fellow engineers through code review, pairing, and technical discussion, giving and receiving feedback in a way that raises the quality of the team's work, not just yours.

Documentation and Communication:

• Create clear technical documentation for system designs, APIs, and processes
• Communicate effectively with stakeholders through technical breakdowns and status updates.

Requirements

Technical Skills:

• Minimum of 7 years of backend engineering experience, with deep expertise in TypeScript and NestJS
• Strong command of PostgreSQL, including schema design for scale, transaction handling, and indexing strategy
• Practical expertise with Redis for caching, coordination, rate-limiting, and distributed locking
• Strong operational understanding of Docker, Kubernetes, and AWS
• Experience working within Agile/Scrum methodologies.

Software Engineering:

• Demonstrated experience in fintech systems, including orchestration, provider integration resilience, and compliance-sensitive design
• Deep understanding of sound architectural trade-offs and patterns that protect correctness in financial systems
• Strong commitment to writing clean, testable, maintainable code.

Professional Skills:

• A track record of owning complex, high-stakes technical work from design through to production, and standing behind the outcomes
• Strong communication skills, with the ability to work effectively across engineering, product, compliance, and external partners
• A demonstrated habit of catching your own issues before they reach QA or production, and of treating failure as something to learn from rather than deflect.

Experience:

• Experience mentoring or raising the technical standard of a team, not just delivering individually
• Demonstrated experience working in fintech or another high-compliance industry.