Paul Underwood
I'm a software engineer in the UK. I build and operate small software products, APIs, developer tools and agent workflows.
Most of my recent work is on Bullion API, PostConductor, Satzo and SeedScore. I write about the decisions behind the work in the Notebook.

Active product
Bullion API
A developer API for current and historical precious metal prices. I built it because market data integrations were harder to reason about than they needed to be.
- My work
- Product direction, API design, authentication, billing, provider integrations and operations.
Visit Bullion API ↗
Active product
PostConductor
A social publishing system designed for people working through AI agents. Its MCP tools are useful to agents while approval stays in human hands.
- My work
- Product direction, MCP and API contracts, authentication, queueing, billing and delivery workflows.
Visit PostConductor ↗A UK crypto tracker built around Section 104 pooling, same-day and 30-day matching rules. In development — screenshot from the staging preview.
- My work
- Product direction, CGT calculation rules, wallet integrations, reporting and operations.
Automated due diligence for companies raising on Crowdcube and Seedrs, scored by AI across ten categories with every point traceable to a source. In development — screenshot from the staging preview.
- My work
- Product direction, research pipeline, scoring rubric, Companies House and news integrations.