Balance

Most budgeting apps either oversimplify (pie charts that tell you nothing new) or overwhelm (spreadsheets with 40 columns). There's a gap for people who want meaningful insight into their spending patterns without needing a finance degree to interpret the data.

A dashboard that automatically categorizes transactions and surfaces trends through purposeful visualizations. Instead of showing everything at once, it highlights what's changed -- unusual spending, recurring charges, and progress toward savings goals.

I built custom D3.js visualizations rather than using a charting library, because the interactions needed to be specific: brushable time ranges, drill-down by category, and animated transitions between views. The backend aggregates transactions from a mock banking API, categorizes them using rule-based matching with a fallback ML classifier, and exposes a REST API consumed by the React frontend. MongoDB stores transactions and user preferences, chosen for its flexible schema when dealing with varied transaction formats.