Toyyo

Inspiration

Owning a car should be exciting, but making financial decisions about it can be overwhelming. Should you refinance your loan, buy out your lease, upgrade your vehicle, or continue with your current plan? The answers depend on countless factors, from monthly payments and credit history to driving habits, mileage, and unexpected life changes.

We realized that while customers have access to plenty of financial information, they rarely have a clear understanding of what they should actually do next.

Inspired by Toyota Financial Services' challenge, "Given my situation today, what's the smartest next move for me and my Toyota?", we created Toyyo, an AI-powered automotive ownership copilot that transforms scattered information into personalized, actionable guidance.

Our goal was simple: make every Toyota owner feel confident about their next move.

What it does

Toyyo is a personalized automotive ownership assistant that helps drivers make smarter financial and vehicle-related decisions.

Instead of presenting customers with complicated statements, disconnected calculators, and overwhelming financial jargon, Toyyo brings their ownership experience together in one interactive platform.

With Toyyo, users can:

Discover their next best move: Receive personalized recommendations about refinancing, lease-end decisions, payment management, insurance, and vehicle protection.
Understand the reasoning: Explore transparent calculations, financial trade-offs, eligibility considerations, and AI-powered explanations behind each recommendation.
Experiment with what-if scenarios: Adjust mileage, payment preferences, and other supported variables to see how their financial options change.
Explore their vehicle interactively: View their Toyota through an immersive 3D experience and navigate driving insights, trip history, and ownership information.
Navigate repairs and maintenance: Compare repair-or-replace considerations and understand potential vehicle ownership costs.
Chat with Toyyo: Ask our AI assistant questions about financial decisions and receive context-aware explanations grounded in the application's calculations.
Take the next step: Explore simulated self-service actions and specialist handoffs, helping customers move from recommendations toward informed decisions.

We also built TFS Insight, a prototype internal dashboard illustrating how Toyota Financial Services could use customer decision context to support more informed specialist conversations and understand potential business value.

Using synthetic customer and financial scenarios, Toyyo demonstrates how intelligent, explainable guidance can simplify the entire vehicle ownership journey.

How we built it

We built Toyyo using Next.js, React, TypeScript, and Tailwind CSS, creating a responsive full-stack web application that combines financial intelligence with an interactive automotive experience.

At its core, Toyyo uses a series of deterministic TypeScript financial engines to evaluate ownership decisions, including lease buyouts, refinancing-related comparisons, payment strategies, insurance considerations, and vehicle protection. These engines calculate costs, evaluate supported alternatives, and provide structured information for recommendations.

We integrated Google Gemini, with optional Anthropic support, to power conversational explanations. Rather than allowing AI to invent financial figures, we designed the system so calculations come from our financial engines while the language model helps users understand the results. We also implemented structured validation and fallback explanations to maintain usability when AI services are unavailable.

For the visual experience, we used Three.js and React Three Fiber to create interactive 3D vehicle models, while Mapbox/MapLibre supports driving maps and trip replay. Recharts helps visualize financial comparisons and driving analytics, and Zod validates API requests and structured data.

We designed Toyyo around synthetic customer profiles and Toyota Financial Services' provided data scenarios to demonstrate how different ownership situations can lead to different recommendations.

The application also includes consent controls, scenario exploration, and a prototype TFS specialist handoff workflow.

Our biggest architectural priority was separating financial computation from AI-generated explanations, making Toyyo more transparent, testable, and reliable.

Challenges we ran into

One of our biggest challenges was combining several complex systems into a single cohesive experience.

Financial accuracy and explainability: Financial recommendations cannot simply sound convincing; they need to be supported by calculations. We had to ensure the AI assistant relied on verified financial data instead of generating unsupported numbers or promising outcomes.

Personalization across different customers: A customer approaching the end of a lease has very different needs from someone refinancing a loan or facing unexpected financial hardship. Designing a recommendation system that handles these situations without giving everyone the same generic advice required careful data modeling and decision logic.

Connecting AI with deterministic engines: Integrating a conversational assistant with structured calculations, eligibility information, and dynamically changing scenarios was challenging, especially while maintaining reliable fallback behavior.

Interactive 3D performance: Building a visually engaging vehicle experience while keeping the dashboard responsive required balancing graphical quality, rendering performance, and usability.

Full-stack integration under time pressure: With multiple teammates developing financial engines, frontend experiences, and AI features simultaneously, coordinating APIs, shared types, and application state was a constant engineering challenge.

Throughout development, we learned that building a trustworthy financial assistant requires much more than calling an LLM API.

Accomplishments that we're proud of

We're especially proud that Toyyo goes beyond a traditional chatbot or financial dashboard.

We built an interactive ownership platform that brings together personalized financial recommendations, vehicle information, driving insights, and conversational assistance.

Some of our favorite accomplishments include:

Explainable financial recommendations backed by deterministic calculations rather than unsupported AI-generated figures.
Interactive what-if simulations that allow customers to explore the impact of changing circumstances.
Immersive 3D Toyota vehicle visualizations that make the experience engaging and distinctive.
A context-aware AI assistant that can explain financial options in understandable language.
Multiple customer scenarios demonstrating how recommendations vary based on different ownership situations.
A prototype TFS Insight dashboard connecting customer guidance to potential business value.
A cohesive, custom-branded interface built around Toyyo and its mascot.

Most importantly, we're proud of creating something that addresses a genuine problem: helping people understand financial decisions that can have a meaningful impact on their lives.

What we learned

Building Toyyo taught us that the most useful AI doesn't replace human decision-making; it helps people make better-informed decisions.

We learned how to combine deterministic financial models with generative AI, validate structured data, build interactive full-stack applications, and communicate complex information through intuitive visual experiences.

We also gained experience designing around real-world constraints such as financial eligibility, customer consent, responsible recommendations, and uncertainty.

On the engineering side, working with Next.js, TypeScript, Gemini, Three.js, mapping tools, and multiple financial engines pushed us to think carefully about modular architecture, integration testing, and collaboration.

Perhaps our biggest takeaway was that personalization is not just showing someone their name or vehicle. It's understanding their circumstances, explaining their options, and helping them make a decision that fits their needs.

What's next for Toyyo

We see Toyyo growing into a proactive automotive ownership companion that supports customers throughout the entire vehicle lifecycle.

Our next steps include:

Real-world integrations: Securely connecting authorized financial accounts, vehicle information, servicing data, and Toyota Financial Services systems.
Proactive Guardian notifications: Alerting users about upcoming financial deadlines, mileage exposure, maintenance needs, and relevant ownership opportunities.
Smarter personalization: Expanding our recommendation engine to support more customer situations and increasingly sophisticated simulations.
Seamless specialist handoffs: Connecting customers with human support while preserving their decision context, preferences, and relevant information.
Expanded AI assistance: Making Toyyo more conversational, proactive, and accessible across different communication channels.
Real-world validation: Testing with users, improving safety safeguards, and measuring whether Toyyo helps customers make more confident decisions.

Ultimately, we envision Toyyo becoming more than a dashboard or AI assistant.

We want Toyyo to be the trusted copilot that helps every Toyota owner navigate their journey, from their first payment to their next vehicle.

Toyyo, Your car. Your next move, made clear.