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I Built a Smart AI Router. It Was Smart Enough to Be a Problem.
My model router was technically working. Then a simple cron fix took ten minutes and the logs showed the real problem: every turn was getting a different brain.
Zachary Guerrero · Design EngineerI design product experiences that survive implementation.
I work where product design and frontend engineering overlap. I investigate the problem, shape the interaction, build the interface, and stay involved through launch and iteration.
My strongest work connects user needs, operational realities, and implementation constraints. I prototype in Figma, contribute in code, and work closely with the people who support and ship the product.
Design + CodeProduct Delivery
UX EngineerAdjacent Role
10+ YearsDesigning & Building
My Expertise
Product design and frontend engineering, connected.
I bring design judgment into implementation, and implementation knowledge back into design. The result is clearer interactions, better edge-case thinking, and product work that is easier for teams to ship and support.
Design Through Implementation
I carry product work from problem framing and interaction design into production interfaces, keeping the rationale intact as constraints emerge.
Ground Decisions in Evidence
I use the evidence appropriate to the work: operational feedback, user research, implementation investigation, and post-launch signals.
Build Systems That Hold Up
I build reusable components, clear workflows, and maintainable foundations that make future product work easier.
Work Across Product Boundaries
I collaborate across product, design, support, and engineering, then contribute in code where implementation context matters.
Shipped Projects
FIELD NOTES
Field Notes
My Capabilities
What's in My Toolkit
Research & Testing
I use the evidence the work makes available: research sessions, operational feedback, prototypes, and post-launch signals.
Design
Tools I Use
- •Figma (daily driver)
- •Pen & Paper (early ideation)
- •Whimsical (flows, maps)
- •FigJam (collaboration)
What I Do
- •Wireframing & prototyping
- •High-fidelity mockups
- •Design systems
- •Visual design & branding
My Approach: Sketch first, prototype to validate, then build systems that scale.
Development
10+ Years Building for the Web
React, Next.js, TypeScript, and Tailwind CSS. I design with implementation constraints in view and contribute directly in code.
View My Code