SUS · the Simplest Underlay Server

Suspiciously simple, yet full-featured. A complete Underlay server in a single file with zero dependencies.

underlay.org · protocol · docs · github

What is Underlay? A protocol for giving structured data a permanent address: you push JSON records and a JSON Schema, and get back a versioned, content-addressed snapshot you can point to forever. Every record, schema, and file is identified by its SHA-256 hash; versions are manifests of those hashes; storage is deduplicated globally and provenance is built in. The canonical documentation and the reference servers live at underlay.org, maintained by Knowledge Futures.

⚠️ This is a demo server.

• No authentication. Everything here is public and world-readable. Do not push anything private, sensitive, or personal.
• Anyone can delete anything. As a courtesy, please don't delete collections less than 24 hours old. Only reach for delete if space is short.
• Storage is capped. 0 MB of 1024 MB used. When it fills, pushes are refused until someone frees space.

Collections

• atlas-obscura-demo/imaginary-lighthouses, Imaginary Lighthouses (2 versions)
• demo/folks, Folks (2 versions)
• demoowner/people, People (0 versions)

＋ new collection

Point an agent at it

Hand your agent this and let it push a collection:

The server at https://sus.knowledgefutures.org is an Underlay node: an HTTP API
for versioned, content-addressed structured data. Its complete API is its source
file: https://raw.githubusercontent.com/knowledgefutures/demo-sus/main/sus.mjs
Read that, then create a collection and push some JSON records with a JSON Schema.
No authentication is needed. Do not include anything private or sensitive, everything
you push is public.

This page is server-rendered HTML; the same data is available as JSON under /api (start at /api/collections). The whole server is one file you can read on GitHub.