btcprice

Bitcoin price tracker UI. Serves an HTML page with live price updates streamed from btcdata, which this server proxies over WebSocket and renders as HTML fragments for HTMX.

Quick Start

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

# Local dev — creates .venv and installs requirements on first run
make run       # starts on port 4000
make tailwind  # watch Tailwind CSS (separate terminal)

Optionally cp .env.example .env to override BTCDATA_URL; without it the code default (http://localhost:4100) applies. make run-local requires a .env defining BTCDATA_LOCAL_URL.

Docker

docker compose up -d starts btcprice only — it does not bring up btcdata. Both compose files attach to the external btc-network, so create it once and start btcdata separately:

docker network create btc-network      # once
cd ../btcdata && docker compose up -d
cd ../btcprice && docker compose up -d

Service	Local dev	Docker
btcprice	localhost:4000	localhost:4041 (container port 4040)
btcdata	localhost:4100	localhost:4102

Inside btc-network, btcprice reaches btcdata as http://btcdata:4102.

Deployment (citadel)

./deploy-citadel.sh

Same method as ../elprice/deploy-citadel.sh: builds the image locally for the target's architecture (citadel is x86_64 → linux/amd64), copies docker-compose.citadel.yml and .env.citadel to /home/pmp/apps/btcprice on the host as docker-compose.yml / .env, pipes the image over SSH with docker save | docker load, and runs docker compose up -d --no-build. No registry involved.

Deployed btcprice listens on http://192.168.50.195:4041 and proxies to the btcdata already running on omarchy (http://192.168.50.42:4102, set via BTCDATA_URL in .env.citadel) — citadel runs no btcdata of its own, so the deployment compose is standalone with no btc-network.

Overridable: BTCPRICE_DEPLOY_HOST, BTCPRICE_DEPLOY_DIR, BTCPRICE_IMAGE_NAME, BTCPRICE_PLATFORM.

Environment Variables

Variable	Default	Description
BTCDATA_URL	http://localhost:4100	btcdata service URL the server proxies to
BTCDATA_LOCAL_URL	—	Used by make run-local instead of BTCDATA_URL
DOCKER_BTCDATA_PORT	4102	btcdata's port inside btc-network (local compose only)
BTCPRICE_PORT	4041	Host port in the citadel deployment (.env.citadel)

The HTTP port is not configurable via environment: make run hardcodes 4000 and the Docker image's CMD hardcodes 4040.

How It Works

The browser loads a page with HTMX and the WebSocket extension, which connects back to btcprice at /ws/price and /ws/strike — the browser never contacts btcdata directly.

Each of those endpoints opens an upstream WebSocket to btcdata (/api/price/ws and /api/strike/ws), converts each JSON message to an HTML fragment (price_json_to_html, strike_json_to_html), and forwards it to the browser. HTMX swaps the received <div id="price-display"> / <div id="strike-display"> into the DOM. Price changes are color-coded (green up, red down). Reconnection is handled by HTMX.

Tech Stack

Python · FastAPI · Uvicorn · websockets · HTMX · Tailwind CSS v4

The Clojure implementation this replaced is on the clojure branch.