DOGE Price Widget
A cached, embeddable price + conversion widget for any site.
A tiny server-side proxy that caches CoinGecko's free API (so a thousand visitors cost you one upstream call) and a self-contained JS widget showing the DOGE price and a two-way USD converter. Utility, not a ticker for speculation - and it runs on any shared PHP host.
What you'll have when it works
- price.php proxy: fetches CoinGecko, caches JSON to disk for 5 minutes, serves it with CORS headers
- widget.js: renders current price + a USD ⇄ DOGE converter, refreshes every 5 minutes
- A copy-paste embed snippet: one script tag + one div
The prompt
Paste this into Claude Code in an empty project folder. It's a full spec, not a wish – the constraints in it (integer koinu, idempotent crediting, testnet asserts) are the difference between a demo and something trustworthy. Read what comes back before you run it.
Build an embeddable Dogecoin price widget with a PHP caching proxy. It must run on ordinary shared PHP hosting (PHP 8.x, no composer, no database) and make very few upstream API calls. Read the whole spec first.
PART 1 - price.php (the proxy)
- Fetches https://api.coingecko.com/api/v3/simple/price?ids=dogecoin&vs_currencies=usd&include_24hr_change=true using file_get_contents with a stream context (10s timeout, a descriptive User-Agent).
- Caches the raw JSON to a file (doge-price-cache.json next to the script) and serves from cache when it is younger than 300 seconds. If the upstream call fails but a stale cache exists, serve the stale cache with "stale": true added. Never let visitors trigger unlimited upstream calls.
- Responds with Content-Type: application/json and Access-Control-Allow-Origin: * so other sites can embed the widget. Include fetched_at (unix time) in the response.
- Write the cache atomically (write temp file then rename) so concurrent requests never read a half-written file.
PART 2 - widget.js
- Self-contained IIFE, no dependencies, no external CSS. Site owners embed:
<div id="doge-price"></div><script src="widget.js" data-api="https://example.com/price.php"></script>
(read the API URL from the script tag's data-api, with a sensible default of same-origin price.php).
- Renders into #doge-price: the DOGE/USD price (4 decimals), the 24h change with a subtle up/down arrow (muted green/red, nothing flashy), "data by CoinGecko" attribution (required by their free tier), and a two-way converter: a USD input and a DOGE input that update each other live.
- Fetches once on load and every 5 minutes; if the fetch fails, keep showing the last numbers with a small "as of HH:MM" note. Inline all styles via a <style> tag the script injects, scoped under #doge-price. Look: clean card, dark-friendly, one gold accent (#E8B93B).
PART 3 - demo.html showing the embed exactly as a site owner would paste it.
Tone constraint: this is a utility widget. No rocket emojis, no "to the moon", no buy prompts.
Deliverables: price.php, widget.js, demo.html, README with embed instructions and the cache behavior explained.The walkthrough
- Paste the prompt into Claude Code; upload the three files to any PHP host (or php -S localhost:8080 to test).
- Open demo.html and confirm price + converter render.
- Reload rapidly and check doge-price-cache.json's timestamp: one upstream call per 5 minutes, no matter the traffic.
- Embed the snippet on a second site to prove the CORS story.
Before this touches real DOGE
- Keep the 5-minute cache (or longer) - it's what keeps you inside CoinGecko's free tier at any traffic level.
- Keep the attribution: it's required by CoinGecko's terms for free API use.
- Resist turning it into a trading ticker; utility widgets age better and communities respect them.
The lessons behind this kit: How Dogecoin actually works