Senior AI Engineer in London

The AI Operating System for Private Capital. Capsa AI Private capital funds have to find potential investments, research and analyse them thoroughly, monitor them over time, drive improvements, and decide when to buy and sell. They’ve got to see through the marketing, outbid the competition, and learn from every deal they do. Historically, these processes have run on people; we are building the AI Operating System that will run them in the future. We’re focused, ambitious, and obsessed with building a category-defining company. In the last 12 months, we’ve grown ARR 15x, achieved product–market fit with leading multi‑billion‑dollar PE firms, and expanded across the US, UK, and Europe. Now we’re doubling down: we’ve raised a large Series A from top‑tier VC investors to scale the team. We’re hiring hyper‑talented people who want to work at the forefront of AI and revolutionise an industry.

At a glance:

• Role: Senior AI Engineer
• Location: London, UK (Hybrid, in‑person 4 days per week)
• Team: Engineering
• Compensation: Top of market. Competitive base + OTE

The role involves taking what you already know about AI systems or about building at the frontier into a category-defining company. You’ll design and ship the core AI capabilities that sit at the heart of our platform, working directly alongside our founding engineers and CTO. Whether you’ve built production LLM systems, designed agentic architectures, or pushed the limits of RAG and reasoning chains, you bring depth most engineers don’t have, and the job is to point that depth at problems the industry has never had good tooling for. This isn’t a place to maintain someone else’s codebase. We hire engineers who want to own things end-to-end from day one, and we give responsibility based on impact, not seniority. Strong execution is the fast track to shaping the technical direction of a high‑growth AI company, building alongside a founding team that will back your best ideas.

The opportunity includes:

• Building the agent’s brain and designing features that give our AI genuine investment expertise.
• Evaluating new models, techniques, and research as they drop.
• Integrating new data sources into the loop and increasing the depth and breadth of analysis the platform can perform.
• Upholding rigorous standards across everything you ship.

Recent projects include:

• Agentic assistant with a finance-focused toolkit and advanced document authoring features
• Scalable document ingestion and indexing pipeline
• In‑house, streaming‑first agent framework
• AI-assisted document editor

Track record required:

• Four or more years building production software, with meaningful time spent on AI/ML systems at a venture‑backed startup or top tech firm.
• You’ve shipped things that mattered, with impact you can speak to.
• Strong Python, hands‑on experience with LLMs, agent frameworks, RAG pipelines, vector databases, and backend infrastructure.
• Domain curiosity, not just technical ability.
• Comfortable at pace in fast-moving environments.

How you operate:

• Low ego, high ownership.
• Hungry and resilient.
• Bias for action over planning theatre.
• Genuinely curious about AI.

If this opportunity excites you, we’d like to meet you. Initial conversations are direct and substantive, going deep on the work, the team, and what you’d own in the first six months. Capsa AI provides equal employment opportunities (EEO) to all employees and applicants for employment without regard to race, color, religion, sex, national origin, age, disability, genetics, sexual orientation, gender identity, or gender expression. We are committed to a diverse and inclusive workforce and welcome people from all backgrounds, experiences, perspectives, and abilities.