Senior Software Engineer - TypeScript / Next.Js / SQL

A growing technology-led business is rebuilding and modernising the core system - including billing, invoicing, reconciliation, integrations, operational workflows, reporting, customer tooling, and internal platforms.

These systems sit at the heart of the organisation and directly influence revenue, operational efficiency, customer trust, and commercial decision-making.

This role is suited to someone who enjoys solving complex operational and data problems, and who takes ownership of outcomes rather than simply delivering tickets.

Strong engineering judgement, systems thinking, and an appreciation for correctness are essential in an environment where mistakes can have meaningful downstream impact.

AI-assisted development is already central to the engineering workflow. Tools such as Claude Code and Cursor are actively used day-to-day, and senior engineers are expected to use them confidently and pragmatically.

What You'll Be Responsible For

Designing and evolving business-critical systems across operations, finance, integrations, and customer workflows

Leading technical investigations into workflows, operational issues, integrations, and data discrepancies

Partnering closely with finance, operations, support, engineering teams, and customers to solve complex business problems

Leading technical and operational discussions with customers over calls and video meetings

Building systems that are accurate, auditable, explainable, scalable, and maintainable

Driving improvements in reliability, observability, documentation, and engineering standards

Using AI-assisted development tools to accelerate delivery while maintaining engineering quality and judgement

Helping shape technical direction, architecture, and long-term platform decisions

Strong TypeScript experience across frontend and backend systems

Deep experience with Next.js, NestJS, and modern backend architecture

Strong SQL and data modelling skills, ideally PostgreSQL

Experience building and maintaining business-critical systems where correctness, auditability, and operational reliability matter

Strong understanding of distributed systems, data flows, reconciliation logic, and failure handling

Comfortable working through operational exceptions, edge cases, and complex integrations

Excellent communication skills with both technical and non-technical stakeholders

Highly Desirable

Go experience, particularly in backend systems, infrastructure, concurrency-heavy workloads, or performance-sensitive services

Experience in logistics, shipping, or supply chain operations

Background in billing, invoicing, payments, finance, audit, or compliance-heavy environments

Familiarity with cloud infrastructure, APIs, and data-heavy integrations

Hands-on experience with AI tooling such as Claude Code or Cursor as part of daily engineering workflows

Up to £75,000 depending on experience

25 days holiday + bank holidays

Flexible working arrangements - 3 days office / 2 days remote

Opportunity to shape systems critical to business operations