Rebuilding Ruby’s Image Processing Layer: Why ruby-libgd Matters for GIS and the Future of Ruby

Ruby on Rails Developer | Ruby, Backend

January 2, 2026

In late 2025, during a RubyConf presentation about disaster-response systems, an uncomfortable truth was stated publicly:

Generating map tiles and images on the server is difficult in Ruby. RMagick and MiniMagick were too slow. ruby-gd is used, but it is poorly maintained.

This was not a theoretical complaint. It came from a team building real-world GIS infrastructure — map tiles, overlays, and image generation for emergency and disaster response.

And they were right.

Ruby has lost its graphics runtime.

That realization is what led to the creation of ruby-libgd.

Ruby’s Silent Regression: Losing the Raster Layer

Over the last decade Ruby evolved into a powerful backend language:

• Rails
• APIs
• background jobs
• concurrency
• data pipelines

But something quietly broke.

Ruby lost its native image processing substrate.

Most applications today rely on:

• MiniMagick → shells out to ImageMagick
• RMagick → huge memory usage, unstable, slow
• ruby-gd → abandoned, unsafe, incompatible with modern Ruby

This is acceptable for thumbnails.

It is not acceptable for:

• map tiles
• GIS overlays
• heatmaps
• satellite data
• disaster response dashboards
• real-time visualization

Those systems require fast in-memory rasterization, not shell commands.

What GIS Really Needs

The RubyConf team was not talking about filters or avatars. They were talking about map tiles.

A modern GIS raster pipeline looks like this:

Vector data (PostGIS, GeoJSON, shapefiles)
        ↓
Rasterization (draw roads, regions, heatmaps)
        ↓
Image encoding (PNG, WebP, JPEG)
        ↓
CDN

The missing piece in Ruby was the middle layer: native rasterization and encoding.

That layer must be:

• fast
• memory-safe
• embeddable
• thread-safe
• not shell-based

That is exactly what libgd provides in C.

Ruby just didn’t have a modern binding.

Why ruby-libgd Exists

ruby-libgd was created because RubyConf 2025 publicly demonstrated a structural gap.

Not a gem gap. Not a framework gap.

A systems gap.

So I built a modern Ruby binding for libgd:

• using Ruby’s TypedData API
• GC-safe
• no external processes
• fully in-memory
• designed for future GIS workloads

What ruby-libgd Provides Today

ruby-libgd already supports:

• Image creation and loading (PNG, JPEG, WebP)
• Drawing primitives:
• Filters:
• Alpha blending
• In-memory composition
• Fast native encoders

All without ImageMagick. All without shelling out.

This is the foundation needed for:

• tile renderers
• overlays
• data visualization
• map layers

Why This Matters for Ruby’s Future

Ruby is increasingly used for:

• infrastructure automation
• data processing
• AI pipelines
• GIS and mapping
• disaster response platforms

But these domains require raster engines.

Without them, Ruby must delegate to:

• Python
• Node
• native microservices

That is fragmentation.

ruby-libgd is the beginning of:

A real Ruby-native GIS raster stack.

The Road Ahead: Toward a Ruby GIS Layer

The long-term vision is not “another image gem”.

It is:

• ruby-libgd → raster core
• PostGIS / RGeo → vector sources
• Ruby → orchestration and APIs

This would allow:

PostGIS → Ruby → ruby-libgd → WebP tiles → CDN

Fully native. Fully Ruby.

This is exactly what the RubyConf 2025 team needed — and didn’t have.

Open Source, but Serious Infrastructure

ruby-libgd is not a toy.

It is:

• C code
• memory management
• pointer safety
• Ruby VM integration
• image encoders

It must be maintained like infrastructure.

That is the commitment behind this project.

Conclusion

RubyConf 2025 exposed a truth:

Ruby is missing a modern image processing backend.

ruby-libgd is the first step toward fixing that.

Not by wrapping shell tools. Not by forking ImageMagick.

But by giving Ruby a native raster engine again.

The future of Ruby in GIS, mapping, and disaster response depends on this layer.

And now, it exists.