Noctua

An image viewer application for the COSMIC™ desktop

Features

• Multi-format support: Raster images (PNG, JPEG, WebP, etc.), SVG vector graphics, and PDF documents
• Navigation: Browse through folders with keyboard shortcuts
• Transformations: Rotate, flip, and crop images
• Zoom & Pan: Flexible viewing with zoom controls and panning
• Multi-page documents: Navigate PDF pages with thumbnail previews
• Metadata display: View EXIF data and file information
• Wallpaper setting: Set images as desktop wallpaper (multi-DE support)

Architecture

Noctua follows Clean Architecture principles with clear separation of concerns.

Key Patterns:

• MVU (Model-View-Update): Elm architecture via libcosmic
• Command Pattern: Domain operations encapsulated in commands
• Dependency Inversion: Domain has no dependencies on infrastructure
• Type-Erased Documents: DocumentContent enum for unified handling

Installation

A justfile is included by default for the [casey/just][just] command runner.

• just builds the application with the default just build-release recipe
• just run builds and runs the application
• just install installs the project into the system
• just vendor creates a vendored tarball
• just build-vendored compiles with vendored dependencies from that tarball
• just check runs clippy on the project to check for linter warnings
• just check-json can be used by IDEs that support LSP

Dependencies

Arch Linux

sudo pacman -S poppler-glib

Debian/Ubuntu

sudo apt install libpoppler-glib-dev

Fedora

sudo dnf install poppler-glib-devel

OpenSUSE

sudo zypper install poppler-glib-devel

Documentation

• Usage
• Features

License

GPL-3.0-or-later