Kharcha Pani - Personal Finance Manager

Problem

Managing personal finances across multiple tools — bank apps, spreadsheets, budgeting apps — creates friction and blind spots. Kharcha Pani consolidates expense tracking, income management, budget planning, investment monitoring, and financial insights into a single, fast application tailored for Indian households.

Architecture

Engineering Decisions

• Feature-based module architecture (modules/expenses, modules/budget, modules/investments) keeps domain logic isolated and testable.
• tRPC with TanStack Query provides end-to-end type safety from database schema to UI components with optimistic updates.
• Drizzle ORM with versioned migrations under drizzle/ ensures schema changes are reviewable and reversible.
• Better Auth handles multi-provider authentication (email, Google, GitHub) with session management.
• AI insights use Google Gemini via the Vercel AI SDK for streaming categorization suggestions and financial health analysis.
• Household finance module supports shared accounts with role-based permissions (owner, admin, member).

Key Features

• Smart Categorization — AI auto-categorizes transactions from descriptions, learning from corrections over time.
• Financial Health Score — A composite metric derived from savings rate, debt ratio, emergency fund coverage, and budget adherence.
• EMI Tracker — Monitor loan repayments with interest type awareness (fixed vs floating).
• Gamification — Achievement system that rewards consistent tracking, budget adherence, and savings milestones.
• Retirement Planning — Long-term projection tools based on current savings rate and investment returns.
• Tax Estimation — Indian tax regime calculations based on tracked income and deductions.

Current Status

The application is in active development with core modules (expenses, income, budgets, investments, subscriptions) functional. Household finance, AI insights, and gamification are being refined. Deployment planned on Vercel with Neon PostgreSQL. It is listed from the rahuljangir.work product home.