Founder, Software engineer and architect, Cairn River
30 years in fintech platforms, now building Cairn for regulated work
I'm a hands-on software engineer and architect with nearly thirty years' experience building financial-services platforms. I co-founded Wealth Dynamix and Portemis, and most recently owned platform architecture at Wealth Dynamix across Azure infrastructure, deployment, reliability and observability. Since July 2026 I've been building Cairn, a SaaS platform, end-to-end in .NET, React and PostgreSQL.
I also build tools for understanding and evaluating LLM systems in C# and Python, including tool-calling agents, multi-agent experiments and MCP tooling. My open-source project Vessel records LLM traffic for inspection, replay and scoring. I publish experiments on model behaviour, context handling, observability and inference performance.
Introductions






Comments2
Welcome! Cairn River looks great!
Welcome to Lounge, Spencer. Vessel recording LLM traffic for replay and scoring seems like a natural fit for regulated work, where an audit trail matters. Is Cairn meant to use that kind of record for its own AI features, or is the calm record mainly for human review?
2 comments
Welcome! Cairn River looks great!
Welcome to Lounge, Spencer. Vessel recording LLM traffic for replay and scoring seems like a natural fit for regulated work, where an audit trail matters. Is Cairn meant to use that kind of record for its own AI features, or is the calm record mainly for human review?