Senior AI Engineer — Build AI Systems for Private Capital

CAPSA; Greater London; Hybrid; GBP 120,000 - 200,000; Full time

Benefits offered by this job

Equity (ESOP)

Hybrid work in London

Career growth opportunities

Job summary

Capsa in London is seeking a Senior AI Engineer to build the AI systems at the heart of a platform used by leading private equity firms. You will design, ship, and improve agents that research companies, analyse documents, and cite every claim, owning the harness end-to-end.

You’ll work across the stack with a team of startup veterans, take real responsibility, and receive meaningful equity as Capsa scales post-Series A. This is a hybrid role with four days in the office per week.

Qualifications

• Five or more years building production backend systems at a venture-backed startup or top tech firm, owning AI powered services end-to-end.
• Experience shipping AI features from ideation to production with measurable adoption and impact.
• Expertise with Python, LLMs, agents, retrieval and search (OpenSearch), evals, and surrounding infrastructure (FastAPI, Postgres, RabbitMQ). TypeScript and React familiarity is a plus.

Responsibilities

• Build AI systems at the heart of Capsa's platform, designing, shipping and improving the agents that perform research, analysis, and citation of outputs.
• Own the harness—from internals to evaluations—that turns demos into trusted enterprise systems.
• Collaborate across the stack with a team of startup veterans to ship robust backend services and AI features.

Skills

Python

LLMs

Agents

Retrieval

Search

OpenSearch

Evals

FastAPI

Postgres

RabbitMQ

TypeScript

React

Tools

OpenSearch

FastAPI

Postgres

RabbitMQ

Job description

Capsa in London is seeking a Senior AI Engineer to build the AI systems at the heart of a platform used by leading private equity firms. You will design, ship, and improve agents that research companies, analyse documents, and cite every claim, owning the harness end-to-end.

You’ll work across the stack with a team of startup veterans, take real responsibility, and receive meaningful equity as Capsa scales post-Series A. This is a hybrid role with four days in the office per week.