Senior Backend Engineer

Senior Backend Engineer London or England remote
London UK Permanent Hybrid

Join a team small enough that what you build is what exists and take agentic AI features from a founders idea to something hundreds of investment firms rely on to make real capital decisions.

What youd actually work on

• Building and shipping production backend services and APIs in Python (FastAPI) that power the platforms AI features used daily by professional investors
• Designing and owning the orchestration layer for agentic AI capabilities: how the system plans calls tools and retrieves the right data at the right time
• Working directly with PostgreSQL and ClickHouse to enable fast reliable data retrieval for AI-driven analysis at real scale
• Taking a feature from a founders rough idea to something live in production within the same sprint without layers of process in between
• Mentoring teammates and helping set engineering standards as the team grows from around seven engineers today to over thirty
• Making real calls on architecture and tooling rather than inheriting decisions frozen in place years ago
• Working closely enough with the founders that your technical judgment shapes what gets built next not just how it gets built

Where it gets technically interesting

• Agentic workflows and tool use sit on top of a data platform that has to stay fast and correct under real investor usage not a demo
• Two different database workloads in the same system: PostgreSQL for transactional data ClickHouse for the columnar analytics-heavy queries behind the AI insights
• AI coding tools (Cursor Claude) are part of the actual day-to-day workflow not a side experiment
• A genuinely small engineering team means no one else is quietly maintaining the parts you dont touch
• Retrieval and embeddings work that has to hold up against messy high-stakes private market data rather than clean public datasets

What were looking for

• 5 to 15 years of backend engineering experience most of it in Python in production environments
• A track record of building and personally owning APIs or services used by real customers not just maintaining systems someone else designed
• Time spent at a startup or scaleup (roughly 30 to 100 people) not exclusively large corporate environments
• Hands-on experience shipping AI or LLM features to production: agentic workflows RAG or tool use
• Strong SQL and solid experience with PostgreSQL or an equivalent relational database
• A genuine preference for staying hands-on and coding day to day rather than moving toward management
• Based in Europe (outside France and the Nordics); if based in London comfortable working from the office five days a week
• Bonus: experience with columnar databases (ClickHouse Redshift Snowflake) or general DevOps/infrastructure skills

The company
An alternative data and private market intelligence platform giving investors real-time data and AI-driven analysis to make faster better-informed decisions. Used by hundreds of leading VC and PE firms across Europe and beyond. Small fast-moving engineering team of around thirty people still shaped day to day by its founders. Equity participation (ESOP) after six to nine months.

Languages: English (fluent working language of the team)

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