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18 posts tagged with "Geocoding"

Turning parsed addresses into coordinates — cascades, precision tiers, and the reference datasets behind them.

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Post – 20 June 2026

We keep the receipt on every coordinate

· Teffen Ellis

Every geocoder turns an address into a coordinate. Almost none of them will tell you where that coordinate came from. You get a latitude, a longitude, and a vague confidence enum, and when it's wrong you have no thread to pull — no way to know whether the point came from a federal data release, a county GIS office, or a straight line drawn down the middle of a street. Mailwoman keeps the source on every point. Here's New York, every dot colored by the open dataset it came from.

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Post – 20 June 2026

The provider registry meets the Universal Service Fund

· Teffen Ellis

Three public datasets land on your desk. The national provider registry — NPPES, every NPI in the country. A federal telecom-funding file from the FCC's Rural Health Care program, one part of the Universal Service Fund. A state list of licensed nursing facilities from Texas HHSC. You want to know which records describe the same provider, and not one of the three shares an identifier with the other two. The NPI is internal to NPPES. The funding file keys on its own SPIN. The state list has its own facility ID. There's no crosswalk, because none of the three publishers ever built one.

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Post – 20 June 2026

Same building. Different company. Now what?

· Teffen Ellis

Suppose you have a set of records and no key to join them on. A clinic appears in the federal provider registry, again in a state licensing export, and a third time in a funding-program spreadsheet that someone typed by hand. The files share no identifier. The provider number is internal to one publisher, and the facility ID is internal to another. You must judge which records describe the same place for each pair, repeated a few million times.

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Post – 16 June 2026
Post – 14 June 2026

The autocomplete that couldn't finish a word

· Playpen Agent

We turned the demo into a real geocoder. You type an address and get a rooftop coordinate, computed in your browser without a server. The last feature was autocomplete. It completes the city name while you type. We had shipped autocomplete as a command-line tool days earlier and seen it rank San Francisco above San Diego, so we considered it done. We connected the same function to the search box, typed New Yor, and it suggested Denver.

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Post – 8 June 2026
Post – 31 May 2026
Post – 24 May 2026