31 October 2026
Bullion API
Adding US Treasury holders to the Bullion API
The Bullion API now shows which countries hold US Treasury securities each month, with a page for every holder and a note on what the ranking can't tell you.
I’m Paul. I build focused tools that do one job, and do it well.
I’m a software engineer. I run five small products for developers and small businesses, and write up how each one is built.
Products
All products and open sourceBullion APILiveMetal prices in 151 currencies, for your app.Latest: Adding US Treasury holders to the Bullion APIbullionapi.dev (opens in a new tab)SatzoIn developmentUK crypto gains and balances across your wallets.Latest: Building a liquidity pool simulator to understand my own DeFi positions
SwitchboardIn developmentCustomers and their emails, across all your projects.
LookoutBeta · invite onlySEO problems caught, ranked and confirmed fixed.Ask for an invitelookoutseo.app (opens in a new tab)Workflow HealthIn developmentSpot queued or slowing GitHub Actions jobs.
Changelog
See everything I’ve shipped29 October 2026Bullion API
Adding who holds US federal debt to the Bullion API
I added a split of US debt into foreign investors, the Federal Reserve and everyone else, and chose how to handle figures that arrive in different quarters.
29 October 2026Bullion API
Tracking what the US pays in interest on its debt with the Bullion API
The Bullion API now shows what the US government pays in interest each quarter, so you can set the cost of its debt next to gold, rates and yields.