What is rgeo?

RGeo is a Ruby library that lets you work with location and geographic data in your applications. If you're building anything that needs to understand maps, coordinates, or spatial relationships, like a delivery app, real estate platform, or location-based service, this library handles the math and data structures for you. At its core, RGeo lets you represent geographic objects like points (a single location), lines (a route), and polygons (an area), and then perform common geographic operations on them. For example, you can check if two areas overlap, create a buffer zone around a point, calculate the distance between two locations, or measure the size of a region. It also handles the tricky part: correctly dealing with Earth's spherical shape rather than treating it as flat, and converting coordinates between different map projections (which matters when you're displaying locations on a flat screen). The library integrates naturally with popular Ruby tools for building web applications. If you're using Rails and a database like PostgreSQL with spatial extensions, or MySQL with spatial capabilities, RGeo has adapters that let your database store and query geographic data efficiently. It can also read and write standard geographic data formats like GeoJSON (which web mapping services understand) and shapefiles (which GIS professionals use). You'd use this if you're a Ruby developer building location-aware applications and need reliable, standards-based tools for handling geographic calculations and data. The library leans on trusted open-source geospatial libraries under the hood (GEOS for calculations and Proj4 for projections), so you get battle-tested geographic logic without having to implement it yourself. Installation requires a few system dependencies, and it works best on Unix-like systems, the README notes that Windows support is limited but possible with some extra setup.