Halupedia

"Comprehensive coverage of topics mainstream encyclopedias overlooked."

An infinite, hallucinated encyclopedia. Every link leads to an entry that does not exist yet — until you click it, at which point an LLM pretends it has always existed and writes it for you, in the deadpan register of a 19th-century scholarly press.

Live at halupedia.com. Cooked on a Cloudflare Worker. Cached forever in KV. Threaded HN-style comments under every article, no signup, AI-hallucinated identities. Patrons may buy us tokens so the press can keep printing. Editors and conspirators meet in the Discord.

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Table of contents

• What it is
• Star history
• How a page is born
• Consistency in a hallucinated universe
• Comments
• Defenses against runaway costs
• Architecture
• Local development
• Deploying your own instance
• Configuration
• Contributing
• License

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What it is

Halupedia is a single-page Cloudflare Worker that:

1. Serves a React SPA that looks like an old print encyclopedia.
2. On a request for any unknown slug, calls an LLM (via OpenRouter) that returns an HTML article in the encyclopedia's voice — full of confident, plausible-sounding nonsense that is densely cross-linked to other entries that also do not yet exist.
3. Caches that article in Cloudflare KV forever. Subsequent visits are free.
4. Lets readers leave HN-style threaded comments without ever signing up. Names are hallucinated by the LLM on first comment and tied to a cookie.

There is no editorial staff, no truth, no warranty. Every article is invented on demand. The footnotes are also lies.

Star history

How a page is born

   you click  ─►  /api/page/footnote-drift
                       │
                       ▼
              ┌──────────────────┐
              │ in KV already?   │── yes ─► stream from KV (free)
              └──────────────────┘
                       │ no
                       ▼
              ┌──────────────────┐
              │ are you a bot?   │── yes ─► 404 (no token spend)
              └──────────────────┘
                       │ no
                       ▼
              ┌──────────────────┐
              │ over IP rate?    │── yes ─► 429 with Retry-After
              └──────────────────┘
                       │ no
                       ▼
              ┌──────────────────────────────────┐
              │ load prior link-hints from D1    │
              │ (canon set by other articles)    │
              └──────────────────────────────────┘
                       │
                       ▼
              ┌──────────────────────────────────┐
              │ stream LLM via OpenRouter        │
              │  → split stream:                 │
              │    a) sanitize + send to client  │
              │    b) collect, persist to KV,    │
              │       extract & save link hints  │
              └──────────────────────────────────┘

The HTML stream is split (ReadableStream.tee()) so the user starts reading the article while the worker is still receiving and persisting it. First paint is sub-second; the worker continues writing to KV under ctx.waitUntil() after the response closes.

Consistency in a hallucinated universe

The hardest problem with an infinite, on-demand encyclopedia is internal contradiction: article A says Mortimer Vellum died in 1843; article B, generated three weeks later, says he was alive in 1881. Halupedia solves this with link hints:

• When the LLM writes an article, it is required to add a context="…" attribute on every <a> it inserts, summarising the future article it is linking to (e.g. context="19th-century clerk who formalized footnote drift, Pellbrick's mentor").
• Before serving the HTML, the worker harvests these context values into a link_hints table in D1, keyed by (target_slug, source_slug).
• The context attribute is stripped before the HTML is sent to the browser — readers never see the metadata.
• When that target article is later requested for the first time, the worker loads the accumulated hints and injects them into the system prompt as "PRIOR REFERENCES — these are CANON". The LLM is instructed that the encyclopedia is hallucinated and absurd, but it must not contradict itself.

The result is a write-forward consistency mechanism: each article seeds breadcrumbs for the entries it links to, so by the time those entries are written, the LLM has a small dossier of established lore to honour.

Comments

Hacker-News-style threaded comments under every article. Backed by Cloudflare D1 (free tier). Notable behaviours:

• No signup, ever. The first time you post, the LLM hallucinates a name and username for you (e.g. Bartram Pellbrick-Thwaite / pellbrick_archivist), in the same scholarly register as the rest of the site. You are inserted into D1 with a UUID and given a hu_uid cookie.
• Cookie is effectively permanent (capped at 400 days per RFC 6265bis, refreshed on every authenticated request — so active users never expire).
• One upvote per comment per user, toggleable. Optimistic UI.
• Threaded to arbitrary depth, sorted by score DESC, created_at ASC.
• Author auto-upvotes their own post, so every comment opens at score 1.
• Per-IP rate limit on identity creation so a botnet can't burn your budget by minting fresh hallucinated names in a loop.

Defenses against runaway costs

LLM tokens cost real money and Halupedia is run by one person who lacks a corporate Amex. The worker has a layered defense:

Layer	Catches	Implementation
1. User-Agent regex	Honest crawlers (Googlebot, GPTBot, ClaudeBot, curl, wget, scrapy, …)	src/worker/index.ts isBot()
2. Per-IP article gen budget	UA-forging scrapers, runaway tabs	KV-backed fixed-window limiter, GEN_PER_IP_PER_HOUR
3. Per-IP identity-mint budget	Cookie-rotating spammers minting hallucinated names	IDENT_PER_IP_PER_HOUR
4. Global daily cap	Distributed botnets that defeat 1–3	MAX_ARTICLES_PER_DAY, KV counter
5. Cache forever	Same slug never costs twice	KV put() with metadata
6. Tee-and-persist	Stream interruptions don't waste a generation	ReadableStream.tee() + waitUntil()
7. Cloudflare dashboard	Volumetric / L7 attacks	WAF rate-limit + Bot Fight Mode

Crucially: cached articles are served to everyone, including bots. The bot guard only fires on uncached slugs, so anything you've already paid to generate stays freely indexable for SEO.

Architecture

src/
├── worker/
│   ├── index.ts        ← Hono app, request routing, generation pipeline
│   ├── llm.ts          ← OpenRouter streaming client + system prompt
│   ├── sanitize.ts     ← HTML allowlist + extracts link-hint metadata
│   ├── hints.ts        ← D1 read/write for cross-article canon
│   ├── identity.ts     ← LLM call that hallucinates {name, username}
│   ├── comments.ts     ← Hono sub-app: threaded comments + voting + cookies
│   ├── ratelimit.ts    ← Per-IP fixed-window KV limiter
│   ├── slug.ts         ← Slug normalisation + reserved-slug list
│   ├── seed.ts         ← Curated seed entries for the homepage
│   └── env.d.ts        ← Worker env type
├── client/
│   ├── App.tsx         ← SPA shell, history routing, streaming reader
│   ├── Comments.tsx    ← Threaded HN-style comment UI
│   ├── AllEntries.tsx  ← A–Z register of every article ever cached
│   └── styles.css      ← Single hand-rolled stylesheet (parchment aesthetic)
├── shared/
│   └── …               ← Types shared between worker & client
└── ...

migrations/
├── 0001_init.sql       ← users, comments, votes
└── 0002_link_hints.sql ← (target_slug, source_slug) → blurb

Stack:

• Cloudflare Workers — execution, runs everywhere, free tier covers viral.
• Cloudflare KV — article HTML cache, stores {title, generatedAt} in metadata.
• Cloudflare D1 — comments, users, votes, link hints.
• Hono — small router + cookie helpers.
• OpenRouter — LLM access (model is configurable via env var).
• Vite + React 18 — SPA, no router library; history API by hand.
• No build step on the worker. Wrangler bundles src/worker/index.ts and serves the Vite output as static assets via the ASSETS binding.

Local development

You will need: Node 20+, pnpm 9, and a Cloudflare account.

pnpm install

# Create a D1 database (one-time)
pnpm wrangler d1 create hallupedia
# Copy the printed database_id into wrangler.toml, replacing the placeholder.

# Apply migrations locally
pnpm wrangler d1 migrations apply hallupedia --local

# Run vite (client) + wrangler (worker) concurrently
pnpm dev

Open http://localhost:8787. Articles will be generated on demand if you set your OPENROUTER_API_KEY (see below); otherwise the homepage seed will display but new entries will fail.

You can hit http://localhost:8787/api/index?refresh=1 at any time to force the total-entries counter to recount the KV namespace.

Deploying your own instance

# 1. Configure secrets
pnpm wrangler secret put OPENROUTER_API_KEY

# 2. Apply migrations to the remote D1
pnpm wrangler d1 migrations apply hallupedia --remote

# 3. Deploy
pnpm run deploy

The Worker handles its own routing, including /robots.txt, the SPA shell, and the API. If you bind a custom domain, edit the [[routes]] block in wrangler.toml. To deploy to a *.workers.dev URL instead, set workers_dev = true and remove the routes.

Configuration

Defined in wrangler.toml under [vars]:

Var	Default	Purpose
OPENROUTER_MODEL	(set in toml)	Model slug used for both article gen and identity hallucination
MAX_ARTICLES_PER_DAY	5000	Global circuit breaker — soft cap per UTC day
GEN_PER_IP_PER_HOUR	100	Per-IP article generation budget
IDENT_PER_IP_PER_HOUR	10	Per-IP cap on minting new commenter identities

Secrets (set via wrangler secret put):

Secret	Purpose
OPENROUTER_API_KEY	Auth for OpenRouter

Bindings:

• ARTICLES — KV namespace for article HTML.
• DB — D1 database for comments + link hints.
• ASSETS — static assets (Vite build output).

Contributing

Pull requests welcome, especially anything that:

• Reduces token spend per article without making the prose worse.
• Improves cross-article consistency further.
• Hardens the bot/UA defenses without breaking real readers.
• Catches a "griffing" / prompt-injection vector you found in the wild.

Please open an issue first for anything user-facing so we can discuss tone — Halupedia lives or dies by its voice and an out-of-register entry is worse than no entry at all.

License

GPL-3.0. The source code in this repository is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

If the press has improved your day, you may buy us tokens or join the conversation on Discord.