Interstellar is a Hugo theme for photography, astronomy, and personal blogging that pairs a tile-based deep-zoom image viewer with privacy-first defaults, including self-hosted fonts and no visitor tracking.
What is Interstellar Hugo?
Interstellar Hugo is a static-site theme built on the Hugo framework and Bootstrap, derived from the Persian Hugo Theme. It converts Markdown content and config.toml settings into a standalone website with a tile-based image zoom viewer, dark mode, and built-in search. The theme is officially developed by Themefisher, Gethugothemes, and Tino Heuberger, and is published under the MIT license. Its core input is a Hugo site's content directory; the output is a fully static HTML site that can be deployed to any host, including Netlify.
Key Features
- Tile-based image viewer — loads high-resolution images in tiles based on zoom level using OpenSeaDragon; supports touch and generates performant zoom. The theme expects a folder containing thumb.webp, tiled_photo.dzi, and a tiled_photo_files directory, typically produced with libvips.
- SVG overlay annotations — an optional annotations.svg file overlays labels or markers on zoomed photos, useful for pointing out celestial objects or details.
- Dark mode and light mode — toggled by setting the
darkmodeparameter to true or false in config.toml. - Custom shortcodes — provides zoomableimage and image shortcodes for embedding deep-zoom viewers and centered images in posts.
- Privacy-first design — captures zero visitor data by default, serves all fonts and assets locally without Google CDNs, and offers optional Google Analytics support.
- Client-side search — built-in fuzzy search powered by Fuse.js, with result highlighting via Mark.js.
- CMS and deployment presets — pre-configured for Forestry CMS and Netlify, including a one-click deploy button and a video tutorial for Hugo + Netlify + Forestry.
- Metadata and consent — generates Open Graph and Twitter Card meta tags, and includes a GDPR consent banner.
Who is it for?
- Astrophotographers — share deep-sky images with the zoomable viewer so viewers can inspect fine details without downloading a massive file.
- Photography bloggers — write posts with centered images and deep-zoom galleries while keeping the site fast and self-hosted.
- Privacy-conscious personal bloggers — run a blog with no default analytics, no external CDNs, and optional GDPR consent, while retaining the ability to enable Google Analytics later.
What can you do with it?
- Showcase high-resolution photography — present a portfolio where each photo can be zoomed in via tile loading, minimizing initial page weight.
- Publish an annotated astronomy blog — use the SVG overlay to label stars, nebulae, or galaxies directly on the image.
- Deploy a zero-tracker blog — host a fast static site with search, dark mode, and a contact form, without any third-party requests by default.
How does the theme work locally?
Clone the repository, move into the exampleSite directory, and run hugo server --themesDir ../.. to start a local development server. The exampleSite includes sample content and configuration that demonstrates the theme's features. Alternately, you can import the repository into Forestry CMS, which will commit changes back and trigger a Netlify deployment.
FAQ
Does Interstellar Hugo collect visitor data?
By default, no visitor data is captured. The theme ships with all fonts and assets hosted locally, and analytics are only loaded if you explicitly enable Google Analytics.
How do I enable dark mode?
In config.toml, add or set the darkmode parameter to true for dark mode, or false for light mode. The theme will then render accordingly.
What files are required for the zoomable image shortcode?
The folder referenced by the shortcode must contain thumb.webp, tiled_photo.dzi, and a tiled_photo_files subdirectory with the zoom-level tiles. The optional annotations.svg file is used for overlays.
Can I use the theme with Forestry CMS?
Yes. The repository includes a Forestry import button and a quick-start configuration. Changes made in Forestry are committed back to the repo and can be deployed automatically with Netlify.
Is Interstellar Hugo free to use?
Yes, the theme is released under the MIT license, so it is free to use, modify, and redistribute, subject to retaining the license notice.
