Senior Backend Developer (Node/Typescript, Accounting experience, AI)

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 Required Skills Strong Node.js/TypeScript experience Worked with financial or accounting software before (MANDATORY) Understand UK tax and VAT rules (or be able to learn them quickly from specifications) Comfortable with AI/ML integration in a production environment. Tech stack: 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