A site is a space (an account's namespace of documents) published at a web domain. Anyone with a browser can read it at https://example.com/about. Anyone with a Seed node can reach the same content as hm://<account>/about. The site's server is a normal Seed node running on a server, plus a web app in front of it.

Sites connect the peer-to-peer network to the web. They give a space a stable place on the internet, a server that is always online to answer for it, and a way to reach readers who have never installed anything.

What a site is made of

A site deployment runs three containers behind one domain:

Piece	What it does
the Seed daemon (`seedhypermedia/site` image)	the libp2p peer that stores and serves the space's blobs; runs with `-p2p.no-relay=true -p2p.force-reachability-public=true`, announces `/dns4/<host>/tcp/56000` and `/dns4/<host>/udp/56000/quic-v1`, keeps its keys in a file keystore
the Seed web app (`seedhypermedia/web` image)	a server-rendered web app that talks to the daemon over gRPC-web, renders documents as HTML, exposes the Seed API at `/api/<Key>` and the site services at `/hm/api/*`, and owns the registration state
a reverse proxy (Caddy)	terminates HTTPS for the domain, sends `/ipfs/*` straight to the daemon and everything else to the web app

An optional notify service sends email notifications for the site. The self-hosting guide walks through running this stack. This page explains what it means at the protocol level.

The daemon has no "site mode" and no site-registration RPC. It does not know it is a site. Two facts that other nodes observe make it one: its web app advertises a registered account at /hm/api/config, and the space's home document names the site's URL.

The home document and `siteUrl`

Every space has a home document at the empty path. hm://<account> is its URL, and its name and icon become the site's title and favicon. When a space is registered with a site, the Seed app writes the site's origin into the home document's metadata as siteUrl (for example https://example.com).

That one attribute does a lot. Every node that reads the home document learns where the space lives on the web. The daemon resolves the space's site peer by fetching https://<siteUrl>/hm/api/config. It treats that peer as the authority tier in discovery. It authenticates to that peer when it holds a writer key for the space, includes private blobs in pushes to it, and lets that peer read the space's private content. A reader's app also uses the URL to offer "open on the web", and the web app uses it to build pretty links. So whoever controls the HTTPS endpoint named in siteUrl holds real trust; see Integrity.

Registration

Registering binds one account to one site. It is a short handshake between the site's web app and the Seed app that holds the account key:

The site's operator (or the hosting service on their behalf) puts a one-time secret into the site's configuration. The setup link looks like https://example.com/hm/register?secret=….

The account owner opens "Publish Site" in the Seed app and pastes that link. The app fetches /hm/api/config and refuses if the site is already registered to a different account.

The app posts {registrationSecret, accountUid, peerId, addrs} to POST /hm/api/register. The web app checks the secret, tells its daemon to connect to the app's peer, stores registeredAccountUid in its config, and subscribes its daemon recursively to the account's whole space so it stays current from then on.

The app connects to the site's peer and pushes the space's home document, with its related material, to it with PushResourcesToPeer. The rest of the space arrives through the site's recursive subscription.

The app publishes a new version of the home document with siteUrl set to the site's origin.

From that moment /hm/api/config advertises the account, the site's pages render that account's home document, and other nodes treat the site's peer as the authority for the space. Until registration completes, the site shows a "not registered" page.

A site's web app can run in two modes. Single-site mode keeps one config.json with the secret, the registered account and the source peer. Multi-tenant mode keeps a service-config.json with a root hostname, a config per named subdomain, and a map of custom domains to subdomains. The request's hostname selects the config. The hosted service on hyper.media runs the second mode. It drives it through POST /hm/api/admin with an admin secret: create-service {name} allocates a subdomain and returns its setup link, create-custom-domain {hostname, service} maps a domain onto it, remove-service and remove-custom-domain undo them, and get-config and configure-service read the whole service config and overwrite one subdomain's config. Subdomain names must match ^[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?$.

`/hm/api/config`

This route describes the site. Any client that has only a web URL starts here:

{
  "registeredAccountUid": "z6Mko5npVz4Bx9Rf4vkRUf2swvb568SDbhLwStaha3HzgrLS",
  "peerId": "12D3KooWEDdEeuY3oHCSKtn1eC7tU9qNWjF9bb8sCtHzpuCjvomQ",
  "protocolId": "/hypermedia/0.9.2",
  "signerAccountUid": "z6Mk…",
  "addrs": ["/dns4/hyper.media/udp/56001/quic-v1", "/dns4/hyper.media/tcp/56001"],
  "hostname": "https://hyper.media",
  "isGateway": true,
  "notifyServiceHost": "https://notify.hyper.media"
}

registeredAccountUid is the space the site serves.

peerId and addrs are how to reach its daemon.

protocolId tells you whether your node can talk to it.

signerAccountUid is a key the web app generated for itself. The server signs with it on its own behalf, for example when a web visitor edits through the site.

isGateway is explained below.

The route is public and answers any origin. The daemon's own HTTP port serves the same path with only peerId, addrs and protocolId, which is enough to bootstrap a libp2p connection from a URL.

The daemon keeps a domain table. Whenever it resolves a siteUrl it records the domain and re-checks https://<domain>/hm/api/config every 30 minutes, storing the last status (success, unreachable, error, unknown), the last successful config and the last error. Daemon.GetDomain returns that row. When the daemon has never fetched the domain, it falls back to what it knows locally: a home document whose siteUrl names the domain. ListDomains lists them all. The Seed app and the SDK use this table to turn https://example.com/about into an hm:// id without a network round trip when the domain was seen before.

Web URLs and canonical forms

A site maps hm:// URLs to web URLs and back. The rules, in order:

Pretty paths. For the site's own registered account, the path is the document path: hm://<account>/about is https://example.com/about. The home document is https://example.com/.

The /hm/ prefix. Any Hypermedia URL becomes a web URL by replacing hm:// with /hm/ and appending the result to the site's origin: hm://aliceaccount/wunderland?v=deadbeef#block-id-1 can be served as https://example.com/hm/aliceaccount/wunderland?v=deadbeef#block-id-1. A site must be able to render any document, including other accounts' documents, because documents link across spaces and a linked space may have no site at all. The reverse conversion needs to know only that the domain runs Hypermedia software. Even if a central server disappears, a saved https://hyper.media/hm/… link still names exactly one hm:// resource.

Query and fragment carry over unchanged: ?v= for a version, &l for "at least this version, prefer latest", #block and range selectors for fragments.

Exports. Appending .md or .json to the document segment returns the document as markdown or JSON instead of a page, with the same ?v= and ?l parameters.

Some path prefixes are reserved on every site and must not be used as document paths: /hm/ (the mapping above and the site services), /ipfs/ (blobs by CID, as an IPFS gateway would), /ipns/ (unused, reserved for compatibility), /.well-known/ (the well-known URI convention) and /api/ (the Seed API). The app discourages creating documents at those paths, and a site must keep working if someone does.

Every rendered page also says which resource it is. A GET or OPTIONS on a document URL answers with X-Hypermedia-Id, X-Hypermedia-Version, X-Hypermedia-Title, X-Hypermedia-Type and X-Hypermedia-Authors headers, and the HTML carries the same facts as <meta name="hypermedia_id"> and <meta name="hypermedia_version"> tags. So a plain curl -X OPTIONS -I https://example.com/about turns a web link into an hm:// id. The SDK's URL resolver does the same when the domain table has no answer.

A canonical-URL and robots policy (which of the pretty and /hm/ forms search engines should index) is an open design note. The web app enforces no such policy today.

What "gateway" means

Three different things share the word:

Bootstrap gateways are the Seed servers compiled into every daemon's bootstrap list: hyper.media, dev.hyper.media, staging.hyper.media and one community node. They are ordinary site daemons that hold nearly everything public and form the first tier of every discovery. Being "connected to hyper.media" means having a libp2p connection to that peer. They are neither a DHT nor relays.

The web gateway flag is SEED_IS_GATEWAY on the web container, surfaced as isGateway in /hm/api/config. A gateway site serves canonical /hm/<account>/… URLs for any account instead of one registered space. It never starts discovery from a server-rendered request. An unknown document renders a placeholder page whose script polls GET /api/DiscoveryStatus, and that first poll starts the daemon's search. This keeps bots that probe thousands of nonexistent paths from queueing expensive discoveries. A non-gateway site discovers server-side and holds the request until the document arrives or times out. The daemon never reads this flag. It only passes it along in the domain table.

The IPFS file gateway is the daemon's GET /ipfs/<cid> route, described on the files page.

hyper.media is all three at once: a bootstrap peer, a gateway site, and a file gateway.

Hosted sites, subdomains and custom domains

The hosting service at hyper.media gives every space a free <name>.hyper.media site. You pick the name in the Seed app's "Publish Site" dialog and the app handles registration for you. Names shorter than four characters are not offered. Short names are rare, desirable and easy to squat, so they are held back. One server can host many spaces, but each space needs its own subdomain, and a subdomain is exactly one space.

A hosted site can also answer on a domain you own. In the Seed app, open the site's options and choose "Publish Custom Domain", enter the domain, and the app asks the hosting service to attach it. Then, at your DNS provider, point the domain at your site: an ALIAS or flattened CNAME record to <name>.hyper.media where the provider supports it. Otherwise use an A record to the address that hyper.media itself resolves to (check with ping hyper.media; it was 40.160.6.196 when this was written and may change). If you use Cloudflare, turn its proxy off for the record. Propagation usually takes about ten minutes. Keep the app open, and the site goes live on the custom domain once the hosting service sees the record. Self-hosted sites do the same thing with their own DNS and the compose file's hostname setting.

A site's content is never locked to its host. The space, the keys and the domain are yours. The self-hosting guide shows how to move.

Working with sites

In the Seed app

"Publish Site" on a space opens the registration dialog. Choose a free hyper.media subdomain, paste a self-hosted setup link, or follow the self-host instructions. After registration the space's settings show the site URL, and publishing a document pushes it to the site with progress per host. "Publish Custom Domain" attaches your own domain to a hosted site. The app's network dialog lists the site's peer among your connections, and the omnibar recognises https:// site links and opens them as hm:// resources.

CLI

The Seed CLI always talks to a site. --server https://example.com (default https://hyper.media) picks the site to read from and publish through, and an https:// argument is resolved against that site's own API. seed-cli document create --site-url https://example.com sets siteUrl on a home document from the command line. That is the only piece of registration the CLI can do. The secret handshake runs from the app. Give any URL argument and the CLI reads /hm/api/config or the X-Hypermedia-* headers to find the hm:// id. The CLI reference lists the flags.

SDK

createSeedClient('https://example.com') is a client for that site's Seed API. resolveHypermediaUrl(url) turns a site URL into {id, version, title, type, authors}. It uses the domain table through GetDomain when available and an OPTIONS request otherwise. resolveIdWithClient(url) returns a client bound to the URL's own origin. client.request('GetDomain', {domain, forceCheck?}) and ListDomains read the daemon's domain table. See the SDK guide.

Web API

The site services under /hm/api/* define a site: GET /hm/api/config (above), POST /hm/api/register ({registrationSecret, accountUid, peerId, addrs}; the desktop's registration call), POST /hm/api/admin (multi-tenant management with an admin secret), POST /hm/api/discover ({uid, path[], version?, media?}, blocking discovery on the site's daemon), /hm/api/file/<cid> and /hm/api/image/<cid> (files), /hm/api/auth (sign-in) and /hm/api/version. The Seed API at /api/<Key> adds GetDomain, ListDomains and DiscoveryStatus. The pages /hm/register?secret=…, /hm/create-site, /hm/connect#… and /hm/download are human entry points. The web API guide documents each with examples.

Agents

Seed Agents and external agents address sites the same way the CLI does. A hosted agent reads and writes through https://hyper.media (or the server it was configured with). It can read https://example.com/about, which resolves through the site's headers to an hm:// id before reading. A space can name an agents server in its home document metadata as agentServerUrl, and list the agents it exposes to visitors as spaceAgents. Then a site's readers see the site's agents in the assistant panel. An agent that drives a site with curl uses /hm/api/config to learn the account and /api/DiscoveryStatus to wait for a document. See using Seed from your own agent.

Where this is going

As of September 2026, the open items around sites are the canonical-URL and robots policy for search engines, exposing subscriptions and domain management through the public API as well as gRPC, and the broader HM26 direction on the roadmap. In that direction a site's authority over a space becomes an explicit, signed relationship instead of a siteUrl string plus an HTTPS lookup.