Initial Hash Wallet price aggregator (Cloudflare Worker)

Single endpoint serving USD spot prices for Hash Wallet, sourcing from
Kraken (majors) and NonKYC (Wownero), KV-cached and refreshed via cron
every minute. Drop-in /v2/rates shape compatible with the existing wallet
client; preferred /v1/prices returns everything in one call.

README.md

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+# hash-wallet-prices
+
+Cloudflare Worker that aggregates USD prices for [Hash Wallet](https://github.com/Such-Software/hash-wallet) and serves them at one cached endpoint.
+
+Why this exists: see the architectural notes in the wallet repo. Short version — having every user's phone hit Kraken/NonKYC directly leaks wallet-holder activity to the exchanges and spreads our rate-limit budget across thousands of IPs. One Worker with a cron-refreshed KV cache fixes both.
+
+## Sources
+
+* **Kraken** — BTC, XMR, LTC, DOGE, ETH, BCH, XNO (all → USD)
+* **NonKYC** — WOW (WOW_USDT, treated as ≈ USD)
+* **Pinned** — USDT, USDC, DAI all return 1.00 (stables we don't quote upstream)
+
+## Endpoints
+
+| Path | Shape |
+| --- | --- |
+| `GET /v2/rates?base=BTC&quote=USD` | `{ "results": { "BTC_USD": 67342.5 } }` — drop-in compatible with the wallet's existing fetch code |
+| `GET /v1/prices` | `{ "rates": { ... }, "sources": { ... }, "fetched_at": "..." }` — preferred, returns everything in one call |
+| `GET /healthz` | `{ ok: true, coins: N, fetched_at: ... }` |
+
+USD-only for now. Other `quote` values return 0 and the wallet falls back to "price unavailable."
+
+## Deploy
+
+```bash
+npm install
+npx wrangler login
+npx wrangler kv:namespace create PRICES
+# Paste the returned id into wrangler.toml's kv_namespaces.id field.
+npx wrangler deploy
+```
+
+After first deploy the worker is live at `https://hash-wallet-prices.<your-cloudflare-subdomain>.workers.dev`. To put it behind `prices.suchsoftware.com`, point that hostname's DNS at Cloudflare and uncomment the `[[routes]]` block in `wrangler.toml`.
+
+## Local dev
+
+```bash
+npm install
+npx wrangler dev          # starts a local server with hot reload
+curl localhost:8787/healthz
+curl 'localhost:8787/v2/rates?base=BTC&quote=USD'
+```
+
+## Adding a coin
+
+1. If Kraken lists it: add `TICKER: "PAIRUSD"` to `KRAKEN_PAIRS` in `src/index.ts`.
+2. If only smaller exchanges list it: add a new fetcher function alongside `fetchNonkyc()` and merge its results in `refreshPrices()`. Keep it `try`/`catch` wrapped so a single source failure doesn't poison the whole refresh.
+
+## License
+
+MIT.