This document outlines the changes made during the repository refactoring from TypeScript/Node.js to Python/Streamlit/PostgreSQL.

The following TypeScript/Node.js files are no longer needed and can be safely removed:

• package.json - Node.js dependency management (replaced by requirements.txt and pyproject.toml)
• package-lock.json - Lock file (if present)
• node_modules/ - Node.js dependencies directory

• tsconfig.json - TypeScript compiler configuration
• banking/banking.ts - TypeScript implementation (replaced by banking/banking.py)
• banking/types.ts - TypeScript types (replaced by banking/types.py)
• banking/banking.test.ts - Vitest tests (replaced by banking/test_banking.py)

• agent-sandbox/ - TypeScript examples (can be removed or kept for reference)
  • Dashboard.tsx
  • example.js
  • package.legacy.json

• app.py - Main Streamlit application
• .python-version - Python version specification
• requirements.txt - Python dependencies
• pyproject.toml - Modern Python project configuration

• db/ - Database package
  • __init__.py - Package initialization
  • connection.py - PostgreSQL connection management
  • models.py - Database data models
  • crud.py - CRUD operations

• migrations/ - Yoyo migration scripts
  • 0001_initial_schema.py - Initial database schema
  • 0002_sample_data.py - Sample data for testing
  • README.md - Migration documentation
• yoyo.ini - Yoyo migration configuration

• banking/banking.py - Business logic (from TypeScript)
• banking/types.py - Type definitions (from TypeScript)
• banking/test_banking.py - Pytest tests (from Vitest)
• banking/__init__.py - Package initialization

• .env.example - Environment variable template
• .streamlit/config.toml - Streamlit configuration
• .gitignore - Updated for Python

• README.md - Updated with Python/Streamlit instructions
• AGENTS.md - Updated with Python guidelines
• CONVENTIONS.md - Updated with Python conventions

To complete the migration:

1. Remove TypeScript files:

   rm package.json tsconfig.json
   rm banking/banking.ts banking/types.ts banking/banking.test.ts
   rm -rf node_modules/

2. Install Python dependencies:

   pip install -r requirements.txt

3. Set up database:

   cp .env.example .env
   # Edit .env with your PostgreSQL credentials
   createdb banking_app
   yoyo apply --config yoyo.ini

4. Run tests:

   pytest

5. Start application:

   streamlit run app.py

• Before: TypeScript + Node.js + Vitest
• After: Python 3.11+ + Streamlit + Pytest

• Before: No database (in-memory only)
• After: PostgreSQL with Yoyo migrations

• Before: No UI (business logic only)
• After: Streamlit interactive web application

• Before: TypeScript interfaces and types
• After: Python dataclasses with type hints

• Before: Vitest with describe/it
• After: Pytest with class-based organization

• Before: npm/package.json
• After: pip/requirements.txt + pyproject.toml

The following were preserved and adapted:

• banking-spec.md - Functional requirements (language-agnostic)
• prompts/ - Prompt experiments (unchanged)
• charts/ - Mermaid diagrams (unchanged)
• docs/ - Static assets (unchanged)

1. Database Persistence - PostgreSQL provides real data storage
2. Interactive UI - Streamlit offers immediate visual feedback
3. Better Typing - Python 3.11+ type hints + mypy validation
4. Simpler Deployment - Single streamlit run command
5. Data Science Ready - Python ecosystem for analytics
6. Professional Tooling - Black, Flake8, MyPy, Pytest