SLIM: Structured Low-bandwidth Information Markup

SLIM is a minimal, text-first HTML authoring profile for delivering reliable, accessible information in low-bandwidth and austere network conditions.

SLIM v1.0 defines strict authoring rules to ensure:

• Text-only content (no images, video, or audio)
• Single-request load model (one HTTPS request to render the page)
• Mandatory TLS encryption
• No scripts, tracking, or third-party fonts
• Inline styles only (with a limited property set)
• No iframes or embedded contexts
• Strong CSP enforcement (recommended)

The specification is authored in Bikeshed format and builds into a W3C-style HTML document for distribution.

Status

• Current version: v1.0 (Unofficial Draft)
• Editor: Caleb Queern (ORCID)
• License: MIT License

Repository Contents

• spec.bs — Bikeshed source for the SLIM specification
• .github/workflows/release-build.yml — GitHub Actions workflow to build HTML/PDF on release
• .zenodo.json & CITATION.cff — Metadata for DOI citation via Zenodo
• LICENSE — MIT License

Building the Spec Locally

pipx install bikeshed
bikeshed update
bikeshed spec spec.bs index.html

Contributing

SLIM is intended as an open, evolving profile.

• Feedback: Open a GitHub Issue
• Changes: Fork and submit a Pull Request

Citation

If citing SLIM in academic or technical work, please use the DOI from the latest release:

Queern, C. (2025). SLIM: Structured Low-bandwidth Information Markup v1.0. Zenodo. https://doi.org/10.5281/zenodo.16790879

ORCID: 0009-0009-4440-8941

Links

• Bikeshed Documentation
• MIT License
• Zenodo