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 and PostConductor. I write about the decisions behind the work in the Notebook.

About me GitHub

Selected projects

All projects

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

Open source

Bullion CLIA TypeScript CLI for live gold prices and historical comparisons.Active · TypeScript

Recent Notebook entries

Browse the Notebook

Email verification belongs at the API boundaryAPIS · 02 Aug Infrastructure questions belong before the first line of codeAI · 02 Aug A status page should explain incidents, not just show greenObservability · 29 Jul Agent workflows should outlive their modelsAI · 27 Jul Building PostConductor: Why I Pivoted to MCP-FirstAI · 01 Jul Stop Blaming the ModelAI · 19 Jun Harness EngineeringAI · 18 Jun A Modern Quality Pipeline and Testing Strategy for Frontend ProjectsGood Code · 17 Jun Agents Are Cron Jobs and Markdown FilesAI · 17 Jun Measure Your Agent Skills or Delete ThemAI · 12 Jun

Available for selected remote product engineering contracts