btcprice

Bitcoin price tracker UI. Serves an HTML page with live price updates streamed from btcdata via WebSocket using HTMX.

Quick Start

# Start btcdata first (provides price data)
cd ../btcdata && make run

# Local dev
make run       # starts on port 4000
make tailwind  # watch Tailwind CSS (separate terminal)

# Docker (starts both btcprice + btcdata)
docker compose up -d   # btcprice on 4041, btcdata on 4101

Environment Variables

Variable	Default	Description
PORT	4000	HTTP server port
BTCDATA_URL	http://192.168.50.42:4100	btcdata service URL (browser connects via WebSocket)

How It Works

The server renders an HTML page with HTMX and the WebSocket extension (hx-ext="ws"). HTMX connects directly to btcdata's WebSocket endpoint (BTCDATA_URL/api/price/ws), which sends HTML fragments. HTMX swaps the received <div id="price-display"> into the DOM automatically. Price changes are color-coded (green up, red down). Reconnection is handled by HTMX with exponential backoff.

Tech Stack

Clojure · Kit · Undertow · Reitit · Hiccup · HTMX · Tailwind CSS v4