---
title: "samueltoh (@propertyxray) | Hashnode"
description: "Founder of Property X-Ray. I write about spatial data, PostGIS, and AI agents. Read the latest articles by samueltoh on Hashnode."
url: "https://hashnode.com/@propertyxray"
---

@propertyxray

# samueltoh

@propertyxray · Melbourne, Australia · Joined June 2026

Founder of Property X-Ray. I write about spatial data, PostGIS, and AI agents.

### [Point-in-polygon: one PostGIS query for geofencing, zones, and spatial lookups](https://samueltoh.hashnode.dev/point-in-polygon-one-postgis-query-for-geofencing-zones-and-spatial-lookups?utm_source=hashnode&utm_medium=feed)

One PostGIS query (ST\_Intersects) handles point-in-polygon: geofencing, delivery zones, spatial lookups, even flood checks. With GeoJSON examples

3 min read · [samueltoh.hashnode.dev](https://samueltoh.hashnode.dev/point-in-polygon-one-postgis-query-for-geofencing-zones-and-spatial-lookups?utm_source=hashnode&utm_medium=feed)

[Jun 21](https://hashnode.com/posts/point-in-polygon-one-postgis-query-for-geofencing-zones-and-spatial-lookups/6a37b7c1d4df69dc09424bd8)