About the role
We’re looking for a senior backend engineer to continue building and shipping production SaaS features at the intersection of AI, accounting, and compliance-heavy systems. You’ll own features end-to-end across backend and AI-driven document workflows.
Responsibilities
The backend developer needs to be comfortable with:
- Building and debugging PDF parsers that can handle messy real-world bank statements from UK high-street banks
- Working with AI/LLM APIs (Claude, GPT-4V) in production, including prompt engineering, cost management, confidence scoring, and PII safety
- Implementing UK tax legislation as code, including VAT schemes, income tax bands, loss reliefs, and HMRC MTD API integration
- Writing reliable async job processing with proper error handling, retries, dead-letter queues, and observability
- Working with PostgreSQL at scale, including complex queries, materialised views, and pgvector for similarity search
- Building a multi-tenant SaaS platform with strict role-based access, period locking, audit trails, and GDPR compliance
- Integrating with third-party APIs such as Open Banking aggregators, HMRC, OCR providers, broker platforms, and Companies House
- Writing and maintaining comprehensive test suites (unit, integration, and end-to-end)
- Debugging production issues under pressure, including stability issues, crash diagnosis, and error-trace analysis
Qualifications
The ideal candidate should have strong Node.js/TypeScript experience, have worked with financial or accounting software before, understand UK tax and VAT rules (or be able to learn them quickly from specifications), and be comfortable with AI/ML integration in a production environment.
tech stack below:
- Node.js / TypeScript
- PostgreSQL
- Redis
- BullMQ
- Open AI
- Claude API (LangChain.js)- To be introduce
- AWS
- Sentry - - To be introduce
- Vitest / Playwright -To be introduce