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.
Oscar Associates (UK) Limited is acting as an Employment Agency in relation to this vacancy.