eth.tennis

Browser-verified ENS gateway. Visit <name>.eth.<GATEWAY_DOMAIN> and the browser resolves the ENS name, fetches the IPFS/IPNS contenthash, and verifies every block against its CID — all through a service worker. The gateway operator hosts only a static bootstrap bundle; no request proxying, no server-side content retrieval.

How it differs from eth.limo

eth.limo is a server-side HTTPS proxy: the operator resolves ENS, fetches the IPFS content, and streams it to the browser. The content the user sees is whatever the proxy returns.

eth.tennis does the resolution and retrieval in the browser. After the service worker activates, the browser queries an Ethereum RPC for the ENS contenthash and pulls content through @helia/verified-fetch, which hash-verifies every block against that contenthash. The server-side surface is only a static bootstrap.

In v1 the Ethereum RPC is still a trust anchor for the name → contenthash mapping. User-configurable RPC and light-client mode are post-v1 work.

How it works

1. Cold visit to vitalik.eth.<GATEWAY_DOMAIN>/path. A static host serves the bootstrap HTML.
2. Bootstrap registers /gw-sw.js, then asks it (via postMessage) to resolve-and-fetch. The SW streams progress lines back, rendered as a boot-log-style terminal.
3. SW uses @ensdomains/ensjs to look up the contenthash, then @helia/verified-fetch to retrieve and verify the content.
4. Bootstrap triggers a reload; the SW now controls the origin and serves content and sub-resources from its primed cache.
5. Warm visits skip the bootstrap entirely — the SW intercepts the first request.

Failures (no contenthash, unreachable content, bad IPNS record, RPC down, etc.) are surfaced by re-rendering the precached bootstrap with state injected into window.__GATEWAY_STATE__. Each class returns a scoped HTTP status.

Packages

Path	Package	License	Purpose
packages/gateway-sw-core	@cypsela/gateway-sw-core	MIT	Reusable SW primitives: ENS resolution, verified-fetch dispatch, errors.
packages/gateway	@cypsela/gateway	AGPL-3.0-only	Deployable site (bootstrap + SW entrypoint). Private; not published.

Content authors who want gateway resolution in their own SW can build on @cypsela/gateway-sw-core, which packages ENS resolution and verified-fetch dispatch as composable primitives.

Develop

pnpm install
pnpm dev                # runs @cypsela/gateway on :5173
pnpm build              # builds both packages
pnpm test               # unit tests (vitest) across the workspace
pnpm ci                 # build + test (what CI runs)

Try http://vitalik.eth.tennis.localhost:5173/ once dev is up — Chromium resolves *.localhost to 127.0.0.1 so no hosts-file edits are required.

Per-package scripts live in packages/*/package.json. @cypsela/gateway also exposes pnpm --filter @cypsela/gateway test:e2e for Playwright.

Environment variables

Read by @cypsela/gateway at build and dev time:

Name	Default	Purpose
VITE_GATEWAY_DOMAIN	gateway.example	Suffix the SW strips from location.hostname to extract the ENS name.
VITE_RPC_URLS	required	Comma-separated Ethereum RPC endpoints. Tried sequentially on failure.

Local defaults live in packages/gateway/.env.development; a template is at packages/gateway/.env.example.

Deploy

Any static host works. TLS must cover every subname depth the gateway is expected to serve (*.eth.<domain>, *.*.eth.<domain>, and so on for ENSIP-10 subnames like app.vitalik.eth.<domain>).

Status

v1 in active development. End-to-end working: ipfs:// contenthashes, ipns:// contenthashes (libp2p-key and DNSLink), subnames, CCIP-read. Fetch timeouts remain a known limitation tracked against the spec.