IndiaInvests: an investment planner that keeps your data on your device

My role

• Wrote an 18-section PRD covering personas and jobs to be done, financial calculation specs with golden test cases, research on Indian statement formats, import reconciliation, security and regulatory boundaries, a metrics plan and risks.
• Directed an AI coding agent (Amazon Quick) through five build rounds and shipped each one live.

What it does

• Calculators for SIP, lump sum, step-up SIP, goal amount, required SIP and inflation, each with a plain-language explanation of the formula.
• Scenario comparison with a lower-return stress path.
• Portfolio import from CSV files and, on a best-effort basis, CAMS and KFintech statements.
• XIRR and time-weighted returns, goals adjusted for inflation, and household planning.
• Encrypted backup and restore, CSV export, and a delete-all option. It installs as an offline app.

Product decisions

• Privacy comes from the architecture. There's no backend, no external API and no login. Everything stays on the device in an encrypted vault, and nothing leaves unless you export it.
• Every number traces to evidence. Historical results come only from imported statements. When a cash-flow history is ambiguous, the XIRR calculation flags it and returns no single rate.
• Projections show their assumptions. Results are labeled pre-tax and assumed, and the starting return and inflation values are editable.
• The advice line is drawn on purpose. The app supports self-directed, educational planning only, so it has no fund rankings and no buy or sell calls.
• The success metric measures benefit to the investor. The PRD's north star is monthly users completing a meaningful plan review, and it warns against counting page views or trading activity as benefit.

Quality

63 unit tests cover the calculation engine, imports, returns, allocation and household planning, and they encode every golden test case from the PRD. GitHub Actions runs the tests, builds and deploys on every push.