short.string.md

Serverless URL shortener. No server, no database, no sign-up.

URLs are shortened client-side using compression or published as aliases to decentralised Nostr relays. Everything runs in the browser — the site is a single static HTML file hosted on GitHub Pages.

How It Works

flowchart TB
    URL["URL Input"] --> Mode{Mode?}

    Mode -->|Compress| Parse["Parse URL"]
    Parse --> Dict["Domain Dictionary\n(github.com → GH)"]
    Dict --> LZ["LZ-String Compress"]
    LZ --> CompURL["short.string.md/#c/..."]

    Mode -->|Alias| Check["Check Nostr Relays\nfor collision"]
    Check -->|Available| Sign["Sign NIP-78 Event"]
    Sign --> Publish["Publish to Relays\n(damus, nos.lol, nostr.band)"]
    Publish --> AliasURL["short.string.md/#n/my-alias"]
    Check -->|Taken| Err["Error: alias taken"]

    CompURL --> Click["Recipient clicks link"]
    AliasURL --> Click
    Click --> Decode{Hash prefix?}
    Decode -->|"#c/"| Decompress["LZ-String Decompress\n+ Domain Lookup"]
    Decode -->|"#n/"| Query["Query Nostr Relays"]
    Decompress --> Redirect["→ Original URL"]
    Query --> Redirect

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Features

Web App (short.string.md)

• Compression mode — LZ-string compression with a domain dictionary (common domains like github.com → GH for shorter output)
• Alias mode — human-readable names stored on Nostr relays using NIP-78
• Zero infrastructure — everything is client-side; the site is a single index.html on GitHub Pages
• P2P swarming — optional WebRTC peer-to-peer relay for alias resolution (via trystero)
• No tracking, no accounts — keys are generated locally and stored in localStorage

Browser Extension (Firefox / Zen)

• Popup — shorten the current tab URL with one click
• Context menu — right-click any link → "Shorten with short.string.md"
• Keyboard shortcut — Cmd+Shift+S (Mac) / Ctrl+Shift+S
• Clickable results — shortened URL opens in a new tab, with a copy button
• History — last 500 shortened URLs, persisted across sessions
• Swarm toggle — opt-in P2P swarming with consent dialog

URL Format

Mode	Format	Example
Compressed	short.string.md/#c/<lz-data>	short.string.md/#c/MYewdgJghsAuC...
Alias	short.string.md/#n/<name>	short.string.md/#n/my-project

Compressed URLs are self-contained — the entire original URL is encoded in the fragment. No server lookup needed.

Alias URLs require a Nostr relay query to resolve.

Install the Extension

1. Download short-string-md-extension-v0.1.0.zip from Releases
2. Extract the zip
3. In Firefox/Zen: navigate to about:debugging → "This Firefox" → "Load Temporary Add-on" → select extension/manifest.json

Domain Dictionary

Common domains are mapped to short codes before compression, reducing output length:

Domain	Code
google.com	G
youtube.com	Y
github.com	GH
reddit.com	R
x.com	X
wikipedia.org	W
stackoverflow.com	SO
...	...

The full dictionary is in index.html and extension/shorten.js.

Architecture

short.string.md/
├── index.html          # The entire web app (single file)
├── CNAME               # GitHub Pages custom domain
├── extension/          # Firefox/Zen browser extension (MV2)
│   ├── manifest.json
│   ├── background.html # Loads bundled libraries
│   ├── background.js   # Context menu, message routing, badge
│   ├── shorten.js      # Compression + Nostr logic (bundled from index.html)
│   ├── popup.html      # Extension popup UI
│   ├── popup.js        # Popup interaction logic
│   └── lib/            # Vendored dependencies
│       ├── lz-string.min.js
│       └── nostr-tools.bundle.js
└── eidos/              # Specs and design documents

License

MIT