MarketPulse AI

MarketPulse AI combines market data, financial news, NLP sentiment (VADER, with an optional FinBERT comparison), explainable machine learning, and rigorous backtesting into one transparent research dashboard — runnable entirely for free in a full demo mode that needs zero API keys. A walk-forward-validated model estimates next-day direction with permutation-importance explanations instead of a black box, and backtests are run against buy-and-hold with transaction costs, drawdown, and hypothetical-results warnings clearly surfaced. An evidence-based assistant answers 'why is this stock moving?' with a deterministic, cited response built from retrieved headlines — no generative hallucination — and a dedicated Status page shows exactly which data sources and models are active. The backend is covered by 96 tests at 89% coverage, plus Vitest and Playwright suites. One highlight: diagnosing and fixing a probability calibration bug where the model reported 97% confidence on near-coin-flip accuracy, then adding a regression test to prevent it recurring.