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©2019-2025 Je Hyun Kim
Based on User Research
The diagram above highlights my approach to user research methodology when designing a new UX and UI at Terra API.
Integrating Generative AI
Previously, building a workout meant dragging and dropping each exercise—a tedious process even for users who knew exactly what they wanted. With generative AI, they can now simply describe the workout to a chatbot and instantly get a tailored session or multi-day plan, with full control to adjust every detail.
Creating a Single Workout Session
Automating Workout Builder
Once a workout is created, coaches can send it directly to their clients’ wearables through Terra’s Planned Workout API. Generative AI builds the plan from the user’s goals, cutting the need to buy pre-made programs and significantly reducing costs for the coaches.
Creating a Workout Plan
Project topic:
Duration:
Skillset:
User research:
UI/UX design, Human centred design, Data visualisation
1 Month
Figma
User journey, User testing, Iterative prototyping
Visualising Health Data
As demand for health scoring tools grew among our customers, we set out to build scores that could translate raw user data into meaningful insights—covering sleep, body stress, cardiovascular health, and workout readiness.
Data Visualisation Details
Customisation
Collaborating closely with data scientists and developers from brainstorming the concept to designing the UI/UX, I focused on how to visualise scores in a way that was both insightful and customisable. Through multiple rounds of prototype testing with real developer users, I refined the design—ultimately introducing a radar graph that balanced clarity with flexibility.
Project topic:
Duration:
Skillset:
User research:
UI/UX design, Human centred design, Data visualisation
3 weeks
Figma
User journey, User testing, Iterative prototyping
Onboarding with Clarity
The original onboarding experience for our developer dashboard created unnecessary friction—users struggled to set up their first workflow and often dropped off early. To streamline this journey, I partnered with the sales team to understand common blockers and redesigned the onboarding flow from the ground up.
Dashboard Onboarding
Understanding Userflow
Using data analytics tools, I studied customers’ behaviours, identified patterns of pain points, and mapped key flows. The result was a simplified, learnable onboarding experience that reduced cognitive load and helped developers get started with confidence.
Authentication Onboarding
Project topic:
Duration:
Skillset:
User research:
UX/UI design, Human Centred Design
1 month
Figma
Funnels, Page view, Engagement time, Session replays
Designing for Scale
To reach large enterprises, we needed more than a generic pitch—we needed to speak their language. Through sales calls, landing page analytics, and user behaviour patterns, I identified distinct enterprise personas and mapped their journey. This research shaped a focused landing page tailored to the needs, values, and decision-making criteria of companies with 10K+ employees - which I designed and coded end-to-end.
Enterprise Product Details
Enterprise Contact Page
Project topic:
Duration:
Skillset:
User research:
UI/UX design, User research, Software engineering
1-month
Figma, Javascript, Typescript, CSS
UX Persona, User journey map, Sales data analytics
Support Page
Blood Report API
Treehacks, 2025
Sponsored Hackathon at Stanford University
Y Combinator AI School, 2025
with Mark Gainey, the founder of Strava
