DBOS Loan Approval Demo

A loan application processing system demonstrating DBOS workflows with AI-powered credit assessment using Google's Gemini.

What is this?

This project shows how to use DBOS Transact to build durable, fault-tolerant workflows in Go. It implements a loan application process with AI-enhanced decision making:

1. Duplicate Check - Prevents processing the same application twice
2. Save Application - Persists loan details to database
3. AI Credit Check - Uses Google Gemini to analyze applicant CVs and assess creditworthiness
4. Document Verification - Validates required documents
5. Manual Approval - High-value loans (>$3000) require human approval via workflow messaging
6. Final Decision - Approve or reject based on all checks

Key DBOS Features Demonstrated

• Durable Workflows: If the process crashes, it automatically resumes from the last completed step
• Workflow Steps: Each operation is checkpointed and recoverable
• Send/Recv Messaging: Workflows can communicate with each other for manual approval processes
• Database Integration: Automatic PostgreSQL schema management and connection handling
• Error Handling: Built-in retry logic and failure recovery
• AI Integration: LLM-powered decision making within durable workflows
• Structured Logging: Comprehensive observability with slog integration

Prerequisites

System Requirements

• Go 1.23+
• PostgreSQL 12+
• Google AI API key for Gemini

PostgreSQL Setup

macOS (with Homebrew)

# Install PostgreSQL
brew install postgresql

# Start PostgreSQL service
brew services start postgresql

# Create database and user
createdb dbos
psql dbos -c "CREATE USER postgres WITH SUPERUSER PASSWORD 'your_password';"

## Running the Project

1. **Prerequisites**: 
   - Go 1.23+
   - PostgreSQL running locally
   - Set `PGPASSWORD` environment variable
   - [Needs to more guide to setup Postgres]

2. **Install dependencies**:
   ```bash
   go mod tidy

3. Run the application:

   go build -o loanapp

   PGPASSWORD=$YOURPASSOWRD ./loanapp

Each step is:

• Durable: Survives crashes and restarts
• Observable: Progress is tracked in PostgreSQL
• [add more!!]

About DBOS

DBOS (Database-Oriented Operating System) makes it easy to build reliable applications by providing durable workflows, queues, and other primitives backed by PostgreSQL.

Learn more: docs.dbos.dev