Hookah

Overview

Hookah is an open-source Radix event-monitoring and webhook-delivery platform by Alex Stelea (xStelea), a prolific author of Radix developer tooling. Developers authenticate with Radix ROLA, register on-ledger event triggers, and receive real-time webhook deliveries when matching events appear in the Radix transaction stream. The stated problem it removes is the one every dApp hits at the same moment: reacting to an on-chain event otherwise means running dedicated nodes or polling a rate-limited API, writing stream-processing and filter logic, and building retrying webhook delivery — infrastructure that has nothing to do with the dApp.

The MIT-licensed repository and the hosted service are both active. hookah.ing served its site, documentation and a live mainnet event stream on 9 August 2026, and the dashboard at app.hookah.ing answered with the ROLA sign-in challenge — the two are separate deployments behind the same domain.

It also has a named production consumer, which is rarer for a one-author tool than a working demo is. Notix, a real-time Radix notification service, credits "Webhook services provided by Hookah" in its footer and links the dashboard at app.hookah.ing (read 15 August 2026). The pairing is the architecture working as designed: a Radix account's state is something you have to pull from the Gateway, Hookah converts matching on-ledger events into an outbound POST, and Notix turns that POST into the notification a user actually receives — three layers, none of which has to run a node.

Architecture

Hookah is a TypeScript monorepo (Turborepo + pnpm) with several components: a Streamer worker that follows Radix transactions and dispatches matching webhook deliveries; a Dashboard (Next.js) serving the web app, authentication, and tRPC/JSON-RPC endpoints; a Docusaurus documentation site; and a webhook test-server helper. It builds on the Radix Gateway API and the radix-web3.js library, with PostgreSQL, Redis, and Drizzle ORM for storage.

The split between the two processes is where the reliability story sits. The dashboard owns writes and migrations; the streamer reads transaction pages from the Gateway, transforms the events, loads candidate triggers from a Redis registry, executes the matching webhooks, writes execution logs, and — per the repository's own description — advances the stream checkpoint only after processing succeeds. A crash mid-page therefore re-reads that page rather than skipping it, which trades a possible duplicate delivery for not silently losing an event. Application logic under packages/api is written with Effect, the same design choice the author made across radix-web3.js.

Triggers and the Webhook Payload

A webhook in Hookah is a destination — a URL, an optional name, and an optional header key/value pair used to authenticate the call at the receiving end. Triggers hang off it. Each trigger names an emitter address and an event name, and the event name must match what the component actually emits, character for character; the published troubleshooting guide lists a mismatched event name and an inactive watcher as the two usual reasons a webhook stays silent.

When a trigger matches, the endpoint receives a POST whose body carries the transaction and the decoded events together:

{
  eventWatcherId: string;
  transactionId: string;
  events: {
    data: ProgrammaticScryptoSborValue;
    emitter: {
      globalEmitter: string;
      methodEmitter: string;
      outerEmitter: string;
    };
    eventName: string;
  }[];
}

The three-part emitter is the detail worth reading twice, because it is what makes a deposit alert workable. For a DepositEvent, globalEmitter is the account, methodEmitter is the internal vault the deposit landed in, and outerEmitter is the resource address — so the payload answers who, where and which token without a follow-up Gateway call. data arrives as programmatic SBOR, the same shape the Gateway returns, so an existing decoder works unchanged. Deliveries are recorded with response codes, error messages, retry attempts and timestamps, and the dashboard can fire a test POST before a real event ever matches.

The SDK

Everything the dashboard does is reachable programmatically through hookah-sdk, published to npm at 1.0.0. Its authentication path is the interesting part: rather than driving a wallet, the SDK takes an Ed25519 keypair and a signer callback, builds a persona proof, and completes the same ROLA challenge the browser flow uses — createEd25519KeyPair and createHookahSdk, then await sdk.auth(). What comes back from getTrpcClient() is a typed tRPC client over the same API surface, so client.webhook.create.mutate({ url }) registers a webhook from a script or a CI job. A JSON-RPC API covers callers that are not TypeScript.

One constraint follows from the design and catches people locally: the API rejects localhost webhook URLs, so testing delivery end to end needs a public HTTPS receiver — the repository's own end-to-end suite reaches for ngrok, and skips those tests when no tunnel is configured.

The Public Repository Is a Snapshot

What is on GitHub is not a running mirror of the service, and the distinction matters before cloning. Every commit on main dates from 5 July 2026 — six of them, all by the author, the first titled "chore: initial open source snapshot". The repository has been public since March 2025 but carries that single day of history.

The deployment has since moved past it. The site the snapshot builds is titled HOOKAH :: MONITOR_THE_RADIX_NETWORK; the page hookah.ing actually serves is titled "Webhooks for the Radix ledger", and it advertises capabilities the published documentation does not describe — field-level conditions on event contents, and a trigger that messages a Telegram chat instead of calling an endpoint. In the snapshot's own docs, conditional filtering is still listed as a V1 roadmap item and Telegram appears only as the support chat. A clone therefore builds the July state, not what the hosted service runs today.

The usual caveats for a one-author tool apply: six commits, one contributor, one star, and no public issue tracker activity. The licence, at least, is unambiguous — an MIT LICENSE file sits in the repository root, which is more than can be said for some of the same author's other work (see radix-web3.js, where npm and the repository disagree).

External Links

• Hookah – hookah.ing
• Documentation
• Dashboard – app.hookah.ing
• Hookah – GitHub
• hookah-sdk on npm
• Alex Stelea (xStelea) – GitHub
• Wiki: radix-web3.js – the same author's package suite, which Hookah builds on
• Wiki: ROLA Authentication