I’ve been building libgd-gis, a pure-Ruby GIS rendering engine on top of the GD graphics library.

The goal is simple: generate maps, tiles, and geospatial visualizations directly from Ruby — without external services, native GIS stacks, or heavyweight dependencies.

What it does • Render GeoJSON layers to PNG • Draw markers, paths, polygons, labels • Generate map tiles server-side • Support animated GIF output • YAML-based styling system • No browser or JS required

Why I built it Ruby has strong web tooling but very limited options for high-performance image generation and GIS rendering. Existing tools are often slow, unmaintained, or depend on external processes.

This project aims to provide:

deterministic server-side rendering

lightweight deployment

full control over output

suitability for APIs, reports, or offline generation

Example use cases • Static map generation for APIs • Logistics / tracking dashboards • Reports and PDFs • IoT / telemetry visualization • Educational tools • Lightweight tile servers

Tech stack Ruby C extension bindings to libgd (via ruby-libgd)

GeoJSON ingestion

Coordinate projection handling

Raster rendering pipeline

Links GitHub: https://github.com/ggerman/libgd-gis RubyGems: https://rubygems.org/gems/libgd-gis