S&P 500 Technical Analysis Dashboard

Technical analysis is the practice of reading price charts and statistical indicators to understand market conditions — not to predict the future, but to characterize the present. Is the market trending or choppy? Is momentum building or fading? Are traders fearful or complacent?

This dashboard tracks the S&P 500 through the lens of the indicators that professional and retail traders actually use. The moving averages (20, 50, and 200-day) smooth out daily noise and reveal the underlying trend — when the faster 50-day crosses above the slower 200-day, it's called a Golden Cross, historically a bullish signal. The RSI measures whether recent price moves have been unusually strong (overbought, above 70) or weak (oversold, below 30). MACD captures momentum: when the MACD line crosses its signal line, direction may be shifting. The VIX is the market's "fear gauge" — it rises when investors are buying protection against a crash and falls when everyone is calm.

How it's built

Data comes from Yahoo Finance via the yahoo-finance2 package — no API key required. The API route fetches ~14 months of SPY daily OHLC data and the current VIX level, then computes all indicators server-side using the technicalindicators library. The client receives pre-computed series; there's no math in the browser.

Charts are rendered with Lightweight Charts by TradingView — the same charting engine used by professional trading platforms. The stacked RSI and MACD sub-panels share a synchronized time axis with the price chart. Responses are cached for 24 hours so repeated visits are instant.

The signal summary strip at the top derives four status chips deterministically from the indicator values — no model, no inference, just thresholds. The logic lives in a pure function with full unit test coverage.