The handoff between design and engineering is where most projects slow down. A designer ships a Figma file. An engineer says "this isn't buildable." Revisions pile up. Timelines slip. Everyone loses.
At To DO BIG, our Designer and Engineer agents work in lockstep from day one. The result? Designs that ship faster, with fewer surprises and less back-and-forth.
The Problem with Traditional Handoffs
Here's what usually happens:
- Designers design in a vacuum. They create pixel-perfect mockups without understanding technical constraints (API response times, data structures, edge cases).
- Engineers code in isolation. They implement what they think the design means, make "small" tweaks for feasibility, and ship something that doesn't match the vision.
- Everyone blames the other side. "This design is impossible." "This code looks nothing like my mockup."
The root cause? Design and engineering are treated as sequential phases instead of parallel, collaborative workflows.
"The best designs are shippable by default. The best code is designed from the start."
Our 3 Rules for Staying Shippable
Here's how our agents collaborate to stay fast and aligned:
The Designer agent doesn't start with a homepage mockup. It starts with a component library: buttons, cards, forms, navigation. These are documented, coded, and tested before any full screens are built. This ensures every design uses buildable, reusable parts.
Before any UI is finalized, the Engineer agent maps out the data structure (API responses, database schemas, state management). The Designer agent then designs for that data model. No more "where does this field come from?" surprises during dev.
While the Designer agent is creating high-fidelity screens, the Engineer agent is already scaffolding the codebase with the component library. By the time the final designs are ready, 70% of the frontend is already built and functional.
Empty states. Error messages. Loading spinners. The Designer agent doesn't just design the "happy path." It designs every state the user might see. This means the Engineer agent never has to invent UI on the fly.
Real Example: Building a Dashboard
Here's how this looks in practice on a recent project:
- Day 1: Strategist agent defines the goal ("Dashboard for sales managers to track pipeline") and the key data points (deals, revenue, conversion rates).
- Day 2: Engineer agent designs the API and data model. Designer agent creates the component library (cards, charts, filters).
- Days 3-5: Designer agent builds full dashboard screens using the component library. Engineer agent scaffolds the dashboard pages with live API data.
- Day 6: Designer agent hands off final designs. Engineer agent swaps placeholders with real components. Launch-ready in under a week.
No surprises. No delays. Just a clean, shippable product.
Takeaways for Your Team
You don't need AI agents to apply these principles. Here's how to implement them with a human team:
- Involve engineers early. Don't wait until designs are "done." Loop them in during wireframing.
- Build a shared component library. Tools like Storybook or Figma's variants feature make this easy.
- Design the data model together. A quick 30-minute session to sketch out your API structure will save days of rework later.
- Prototype, don't polish. Ship low-fidelity prototypes to validate concepts before investing in pixel-perfect mockups.
The goal isn't perfection. It's shippability.