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Carputty

Director of Product (June 2021 - February 2023)

Carputty was building a next-generation auto line of credit platform designed to provide fairer, more transparent vehicle financing through technology and data-driven underwriting.

The Business Context

Auto lending in 2021 was ripe for disruption. Traditional lenders relied heavily on stated income and credit scores, which often disadvantaged non-W2 workers like contractors, freelancers, and small business owners. Carputty's vision was to use actual bank data to make more accurate, bias-free lending decisions.

The challenge: How do you automate income verification at scale while maintaining accuracy and regulatory compliance?

The Manual Process Problem

When I arrived, Carputty's underwriting team was manually analyzing bank statements in Excel spreadsheets - a process that was:

Extremely time-consuming

Each application required 30-45 minutes of manual review

Inconsistent

Different underwriters categorized income differently

Error-prone

Manual data entry and calculation mistakes were common

Unscalable

Growth required proportional headcount increases

Biased

Human judgment introduced potential for unconscious bias

This manual bottleneck was preventing Carputty from achieving their vision of fast, fair, automated lending decisions.

Building the AI Solution

Phase 1: Understanding the Domain

I spent weeks working alongside underwriters to understand exactly how they analyzed bank statements:

  • What patterns indicated reliable income vs. one-time deposits
  • How they handled irregular contractor payments
  • What red flags suggested inflated or fraudulent income claims
  • How regulatory requirements shaped their decision-making

Phase 2: Designing the ML Architecture

Working with our engineering team, I architected a solution that:

Automated pattern recognition

ML models identified income types from transaction descriptions and amounts

Maintained human oversight

Low-confidence predictions were flagged for manual review

Enabled continuous learning

Underwriter corrections fed back into model training

Preserved audit trails

Every decision was logged for regulatory compliance

Phase 3: Building the User Experience

The interface had to work for underwriters who weren't technical:

Pre-categorized suggestions:

AI showed its best guess for each transaction

One-click corrections:

Underwriters could easily override incorrect categorizations

Confidence indicators:

Visual cues showed which predictions to trust vs. review

Summary dashboards:

Clear income calculations with supporting evidence

Technical Implementation

Data Pipeline

Plaid integration for direct bank data access and real-time transaction analysis

Real-time transaction categorization using NLP and pattern matching

Confidence scoring for automated vs. manual review routing

ML Models

Transaction classification based on description text and amount patterns

Debt-to-Income calculation and income stability analysis for non-traditional income

Fraud detection for unusual or suspicious patterns

Regulatory Compliance

Complete audit trails for all automated decisions

Human review requirements for edge cases

Documentation supporting fair lending practices

The Results

The impact was transformational for Carputty's operations:

1200%
Productivity Increase

From 30-45 minutes per application to 2-3 minutes for AI-reviewed cases

100%
Boost in Auto Approvals

High-confidence cases required no human intervention

33%
Fully Automated

Complete straight-through processing for clear-cut cases

Business Impact

Enabled rapid scaling without proportional headcount increases

Improved consistency and reduced human error in income calculations

Positioned Carputty as technology leader in automated underwriting

Created competitive advantage for loan resale in secondary markets

Customer Experience

Dramatically reduced time from application to decision

More objective, data-driven loan approvals

Better outcomes for non-traditional income borrowers

Press Recognition

"By harnessing the power of AI, we provide an enhanced user experience and make finance decisions based solely on objective data, free from any influence of subjectivity, misaligned incentives, or biases."

— Patrick Bayliss, CEO, Carputty

Read full press release (September 2023)

Strategic Lessons

Domain expertise is crucial

The solution only worked because I deeply understood the manual process first. You can't automate what you don't understand.

Human-AI collaboration beats pure automation

Rather than replacing underwriters, we augmented their capabilities - they could focus on complex cases while AI handled routine decisions.

Regulatory considerations shape product design

In financial services, compliance isn't an afterthought - it has to be built into the core architecture from day one.

Measurable impact drives adoption

Having clear productivity metrics made it easy to demonstrate value and get organizational buy-in for the new process.