Fullstack Engineer

Full Stack Engineer | Central London (3 days onsite)

Our client is an AI work-execution platform built for alternative investment firms and their portfolio companies. It securely brings together proprietary data, external sources and workflows, so investment teams can analyse faster, cover more ground and make better decisions. They are backed by a large, established parent group with deep domain expertise. The team in London is small, senior and high-ownership, with direct access to senior leadership.

They are hiring a Full Stack Engineer (5+ years) to design, build and ship the product end to end, from the database to the UI. Security, tenant isolation and auditability are core engineering constraints, because clients trust the platform with confidential financial data.

What you'll do

• Build data-heavy, accessible interfaces in TypeScript and React, respecting a detailed role-based access model
• Design services and REST APIs in Python (FastAPI/Django) with clear OpenAPI contracts
• Model data in PostgreSQL: schema design, migrations, indexing and multi-tenant isolation
• Build event-driven and background processing, plus real-time features over WebSockets
• Implement SSO, OTP and session/JWT auth, and integrate with Microsoft 365, CRMs and document stores
• Work with the AI/ML team to ship LLM-powered features, including UX that investment professionals can trust and audit (citations, provenance, approve flows)
• Ship and operate on AWS with solid CI/CD, observability and SOC 2 / UK GDPR awareness

✅ What you bring

• 5+ years of software engineering with real full-stack ownership in production
• Strong TypeScript, React, Python and PostgreSQL
• Auth and access control experience in a multi-tenant B2B product
• AWS (or similar), CI/CD and containers
• A track record of setting technical direction and leading architecture decisions
• Daily use of AI coding tools (Cursor, Claude Code or similar) and a considered view on where they help

Nice to have

Next.js/Node.js, LLM product work (streaming, LangChain/LangGraph, MCP), Celery, Redis, OpenSearch, Kubernetes or Terraform, and financial-services or regulated-environment experience.

What's on offer

• Close work with a leadership team with 20+ years of experience in the alternative investment space
• Competitive compensation
• The chance to build something impactful for leading financial services firms
• A collaborative, supportive culture and a central London office

Education: Bachelor's degree in engineering, computer science or a related field, or equivalent experience.

The client's name is shared with shortlisted candidates under NDA. Interested? Message me to start a confidential conversation.

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