UX Engineer, HCI

📍 Job Overview

Job Title: UX Engineer, HCI

Company: Bjak

Location: Seoul, South Korea

Job Type: Full-time

Category: UX Engineering / Human-Computer Interaction (HCI)

Date Posted: 2026-06-02

Experience Level: Mid-level (2-5 years)

Remote Status: Remote (with potential for hybrid in Seoul)

🚀 Role Summary

• This role sits at the critical intersection of design and engineering, focusing on building novel AI-native interfaces that users will directly interact with.

• The primary objective is to prototype, test, and ship new Human-Computer Interaction (HCI) patterns for AI-driven experiences where established conventions are still emerging.

• Responsibilities include creating functional prototypes for AI interfaces, translating design concepts into high-fidelity, responsive code, and collaborating closely with product, design, and ML teams.

• This position is ideal for an engineer who excels in ambiguous environments, possesses strong UX instincts, and is passionate about making AI behavior understandable, controllable, and useful in real-world workflows.

📝 Enhancement Note: The job title "UX Engineer, HCI" and the description strongly indicate a role focused on the user's interaction with AI systems, emphasizing the design and engineering of interfaces that manage AI behavior, rather than a traditional operations role. The "remote_derived": true and "location_type": "TELECOMMUTE" suggests a remote-first approach, though the "locations_derived": ["Seoul, South Korea"] and "ai_work_arrangement": "Hybrid" might imply an expectation for occasional presence or a preference for candidates within that region for hybrid work. Given the role's focus, it's not directly a Revenue Operations, Sales Operations, or GTM Operations role, but rather a product engineering role with a strong UX/HCI component.

📈 Primary Responsibilities

• Interface Prototyping & Development: Build and iterate on AI-native product interfaces across web and mobile platforms, ensuring high fidelity, responsiveness, and engaging motion.

• HCI Interaction Model Innovation: Develop functional prototypes for novel HCI interaction models, including but not limited to streaming responses, multi-step task flows, real-time feedback loops, and clear system state visibility.

• Design-to-Code Translation: Translate intricate design concepts into working code, with a meticulous focus on usability, responsiveness, and effective use of motion to enhance the user experience.

• AI Behavior Visualization: Design and implement UI patterns that clearly communicate AI progress, uncertainty, confidence levels, failure states, and recovery mechanisms to the user.

• User Control & Supervision Interfaces: Create interfaces that empower users to supervise, correct, and redirect AI behavior effectively without requiring micro-management of the system.

• Cross-Functional Collaboration: Work intimately with product managers, UX designers, and Machine Learning (ML) engineers to rapidly validate and iterate on interaction ideas.

• Frontend Architecture & Component Development: Contribute to the overall frontend architecture and develop reusable UI components specifically for AI product surfaces.

• Usability & Performance Optimization: Identify and resolve usability issues, performance bottlenecks, and state management challenges within AI-driven interfaces.

📝 Enhancement Note: The responsibilities are heavily focused on product development, UI/UX, and HCI for AI products. While these roles often require close collaboration with operations teams (e.g., providing feedback on how AI tools impact workflows), the core duties are not directly within the scope of traditional Revenue, Sales, or GTM Operations. The emphasis on "AI-native product interfaces," "HCI interaction models," and "AI behavior visualization" clearly places this role in product engineering.

🎓 Skills & Qualifications

Education: While not explicitly stated, a Bachelor's or Master's degree in Computer Science, Human-Computer Interaction, Design, or a related field is typically expected for roles involving advanced UX engineering and HCI.

Experience: 2-5 years of relevant experience in frontend engineering with a strong focus on user interface development and interaction design.

Required Skills:

• Frontend Engineering Proficiency: Strong command of modern frontend technologies, specifically React and TypeScript, or equivalent modern JavaScript frameworks.

• Experimental Interface Development: Proven experience in building interaction-heavy, experimental, or cutting-edge user interfaces.

• Product & UX Acumen: Exceptional product sense and user experience (UX) instincts, with the ability to critically assess and identify usability flaws.

• Rapid Prototyping: Demonstrated ability to rapidly prototype and iterate in ambiguous environments, often with incomplete specifications.

• UI/UX Fundamentals: Solid understanding of animation principles, responsiveness, frontend architecture patterns, and UI performance optimization techniques.

• HCI Interest: A genuine interest in Human-Computer Interaction (HCI) principles and a strong desire to design for trust, control, transparency, and graceful recovery in AI systems.

• Cross-Disciplinary Comfort: Comfort working at the boundary between design and engineering, effectively bridging gaps without rigid handoffs.

• Agile Execution: Ability to move with speed and agility while maintaining a clear and usable user experience.

Preferred Skills:

• Experience with streaming data and real-time UI updates.

• Familiarity with state management libraries beyond basic React hooks.

• Experience designing for mobile-first or responsive web applications.

• Knowledge of accessibility standards (WCAG) and their implementation.

• Exposure to AI/ML concepts and their user-facing implications.

📝 Enhancement Note: The requirements are geared towards a highly skilled individual contributor in product development. The emphasis on "experimental interfaces," "ambiguous environments," and "boundary of design and engineering" suggests a need for someone who is proactive, adaptable, and can self-direct. The "2-5 years" experience level aligns with a mid-level engineer capable of independent work and contribution to architectural decisions.

📊 Process & Systems Portfolio Requirements

Portfolio Essentials:

• Interactive Prototypes: Showcase functional prototypes that demonstrate innovative interaction models, particularly those involving dynamic or AI-driven elements.

• Case Studies of Complex Interfaces: Present detailed case studies of past projects where you built complex, interaction-heavy interfaces, highlighting the challenges and your solutions.

• AI/Experimental UX Examples: Include examples of work that explicitly addresses AI interaction, user control over AI, or experimental UI patterns, even if these were personal projects or conceptual explorations.

• Demonstration of Speed & Iteration: Highlight projects where rapid prototyping and iteration were key to validating concepts or achieving user feedback.

Process Documentation:

• Workflow Design for AI Interfaces: Document the process by which you design and develop workflows for AI interactions, focusing on user control, feedback loops, and error handling.

• Rapid Iteration & Validation Methods: Detail your methodology for rapid iteration and validation of UI/UX concepts, especially in the context of new AI interactions.

• Cross-functional Collaboration Processes: Illustrate how you collaborate with design, product, and engineering teams to bring AI interface concepts to life, emphasizing efficiency and shared understanding.

📝 Enhancement Note: For a role like this, the portfolio is paramount. It needs to demonstrate not just coding ability but also a deep understanding of HCI and the ability to translate abstract concepts into tangible, user-friendly experiences, especially for AI. The emphasis should be on how they approach problems and what they've built that pushes boundaries, rather than just listing technologies.

💵 Compensation & Benefits

Salary Range: Based on the role (UX Engineer, HCI), experience level (Mid-level, 2-5 years), and location (Seoul, South Korea), a competitive salary range would typically fall between ₩60,000,000 to ₩90,000,000 KRW annually. This estimate considers the high demand for skilled engineers in AI and UX, as well as local market rates for specialized tech roles in Seoul.

Benefits:

• Comprehensive Health Coverage: Medical, dental, and vision insurance plans.

• Competitive Paid Time Off: Generous vacation, sick leave, and public holidays.

• Professional Development Stipend: Budget for conferences, workshops, courses, and certifications relevant to UX, HCI, and frontend engineering.

• Remote Work Support: Stipend or reimbursement for home office setup and ongoing remote work expenses.

• Stock Options/Equity: Potential for equity in a growing AI startup.

• Team Events & Retreats: Opportunities for in-person connection and team building, potentially in Seoul or other company locations.

Working Hours: The standard working hours are expected to be around 40 hours per week, aligning with full-time employment. However, the role emphasizes agility and rapid iteration, suggesting flexibility in daily schedules to accommodate project needs and effective collaboration, especially across different time zones if applicable.

📝 Enhancement Note: Specific salary and benefits are not provided, so this is an estimate based on industry standards for similar roles in Seoul. The "remote_derived": true and "ai_work_arrangement": "Hybrid" suggests a flexible work environment, which is a key benefit for many tech professionals.

🎯 Team & Company Context

🏢 Company Culture

Industry: Artificial Intelligence (AI) / Smart Assistant Technology. Bjak is focused on building a proactive AI smart assistant designed to bring intelligence to everyday conversations, errands, organization, and workflows.

Company Size: The description suggests a "small, world-class team" with "high talent density." This typically implies a startup environment with fewer than 50 employees, fostering agility, direct impact, and close collaboration.

Founded: The founding date is not specified, but the focus on building a "proactive AI smart assistant" indicates a company in its growth or scaling phase, likely with a strong emphasis on product innovation and market penetration.

Team Structure:

• High Talent Density: The team is composed of highly skilled individuals who are hands-on and capable of independent execution.

• Collective Decision-Making: Decisions are made collaboratively, fostering a sense of shared ownership and input.

• Agile & Fast-Paced: The team operates with rapid speed, balancing the need to ship high-quality work with continuous learning.

• Cross-Functional Integration: Close collaboration is expected between product, design, ML, and engineering teams to rapidly validate and iterate on AI interaction ideas.

Methodology:

• Data-Driven Insights: Implicitly, the development of an AI assistant relies heavily on user data and feedback to refine intelligence and workflow capabilities.

• Iterative Development: The emphasis on rapid speed, shipping high-quality work, and learning points to an agile, iterative development methodology.

• User-Centric Design: The core of the role is about creating interfaces that are understandable, controllable, and useful to users, highlighting a strong user-centric approach.

• Innovation in AI Interfaces: A key methodology is the exploration and implementation of novel HCI paradigms for AI, moving beyond traditional UI patterns.

Company Website: https://bjak.my/en/about-us

📝 Enhancement Note: The company culture is described as high-talent, fast-paced, and collaborative, typical of an early-stage tech startup focused on cutting-edge AI development. The explicit mention of "high talent density" and "small, world-class teams" means candidates should expect to be challenged and to work alongside very skilled peers.

📈 Career & Growth Analysis

Operations Career Level: This role is classified as a mid-level UX Engineer (2-5 years of experience). It is a hands-on individual contributor role focused on building and shipping product features, specifically AI interfaces. The "UX Engineer, HCI" title suggests a specialization within frontend engineering that bridges design and user interaction, with a particular focus on AI.

Reporting Structure: While not explicitly stated, in such a "small, world-class team" environment, direct reporting lines are often to a Head of Engineering, CTO, or a Lead Engineer/Designer. The collaboration is described as close and collective, suggesting a flat hierarchy in daily work.

Operations Impact: Although not a traditional "operations" role, this position has a significant impact on the product's success and user adoption. By creating intuitive and effective AI interfaces, this role directly influences how users perceive and interact with the AI assistant, thereby driving engagement, retention, and the overall value proposition of the product. A well-designed interface can make complex AI functionality accessible and useful, directly contributing to the company's mission and potential revenue generation through user acquisition and satisfaction.

Growth Opportunities:

• Specialization Deepening: Opportunity to become a domain expert in AI-driven HCI, a rapidly growing and high-demand field.

• Leadership in Product Development: As the company grows, there will be opportunities to take on more significant architectural responsibilities, lead feature development, or mentor junior engineers.

• Broader Skillset Development: Exposure to AI/ML concepts, product strategy, and rapid iteration methodologies will broaden the candidate's overall tech skill set.

• Impact on a Novel Product: The chance to significantly shape a new product category and its user experience from an early stage.

📝 Enhancement Note: This role offers a strong growth path in a specialized and future-forward area of technology. The emphasis is on developing deep expertise in AI HCI and contributing to a foundational product, rather than climbing a traditional corporate ladder.

🌐 Work Environment

Office Type: The "location_type": "TELECOMMUTE" and "remote_derived": true, combined with "ai_work_arrangement": "Hybrid," suggests a flexible work environment. This could mean a primarily remote setup with optional access to a physical office space in Seoul for collaboration, meetings, or focused work, or it could be a hybrid model where specific days are expected in an office.

Office Location(s): Seoul, South Korea. Specific office details are not provided, but for a hybrid or occasional in-office component, it would be a professional workspace designed for collaboration and innovation.

Workspace Context:

• Collaborative Atmosphere: The culture emphasizes collective decision-making and rapid iteration, suggesting a dynamic and interactive workspace, whether remote or in-person.

• Access to Technology: As a tech company building AI products, expect access to modern development tools, robust infrastructure, and potentially cutting-edge hardware for prototyping.

• Cross-Functional Interaction: Opportunities for direct interaction with product managers, designers, and ML engineers are integral to the role, fostering a rich learning and collaborative environment.

Work Schedule: A standard 40-hour work week is implied for full-time employment. However, the emphasis on "rapid speed" and "shipping high quality work" suggests that flexibility may be afforded, allowing individuals to manage their schedules to meet project deadlines and foster effective collaboration, particularly if team members are distributed.

📝 Enhancement Note: The work environment is likely dynamic and adaptable, catering to individuals who can thrive in a fast-paced, collaborative, and potentially hybrid or remote setting. The key is effective communication and project execution, regardless of physical location.

📄 Application & Portfolio Review Process

Interview Process:

• Portfolio Submission: A portfolio is a mandatory part of the application for design-related roles, including this UX Engineer position.

• Initial Screening: Applications will be evaluated by team members.

• Interview Rounds: Expect approximately two rounds of interviews. These will likely be virtual meetings, with the possibility of onsite interviews.

• Design Assessment: A specific design assessment or technical challenge is part of the process.

• Decision & Offer: The company values transparency and efficiency, aiming for prompt decisions and extending offers to exceptional candidates.

Portfolio Review Tips:

• Showcase AI/HCI Focus: Prioritize projects that demonstrate your ability to design and engineer interfaces for AI systems, experimental interactions, or complex user flows.

• Highlight Rapid Prototyping: Include examples where you quickly iterated on designs or built functional prototypes to validate concepts under ambiguity.

• Demonstrate Technical Skill: Clearly articulate the technologies used (React, TypeScript), design patterns implemented, and any specific challenges overcome in making interfaces responsive, performant, and usable.

• Tell a Story: For each project, explain the problem, your role, the design/engineering process, the solutions you implemented, and the impact or learnings. Quantify results where possible.

• Clarity on Collaboration: If possible, show how you collaborated with designers, product managers, or engineers.

Challenge Preparation:

• Understand the AI Context: Be prepared to discuss how users interact with AI, the challenges of AI transparency, control, and error handling.

• Technical Proficiency: The design assessment will likely test your frontend engineering skills (React, TypeScript) and your ability to translate design requirements into code quickly and effectively.

• Problem-Solving: Be ready to tackle a problem related to designing an interface for a novel AI interaction, focusing on user experience and technical feasibility.

• Communication: Practice articulating your thought process, design decisions, and technical choices clearly and concisely.

📝 Enhancement Note: The interview process is designed to be efficient and focused on assessing practical skills and cultural fit. The portfolio and design assessment are critical components, emphasizing hands-on ability and a specific understanding of AI HCI.

🛠 Tools & Technology Stack

Primary Tools:

• Frontend Framework: React, TypeScript.

• Version Control: Git (likely GitHub, GitLab, or Bitbucket).

• Prototyping Tools: Figma, Sketch, Adobe XD, or similar for design mockups and interactive prototypes.

• Project Management/Collaboration: Tools like Jira, Asana, Trello, or Slack for team communication and task tracking.

Analytics & Reporting:

• Web Analytics: Google Analytics, Amplitude, or similar for tracking user behavior on web interfaces.

• Performance Monitoring: Tools for monitoring UI performance and identifying bottlenecks.

CRM & Automation:

• Not directly applicable to this role's core function, but awareness of how user interactions feed into broader CRM or customer data platforms might be beneficial. AI/ML Specific Tools:

• Awareness of AI model APIs, real-time data streaming technologies (e.g., WebSockets), and potentially specific libraries for handling AI model outputs or feedback loops.

📝 Enhancement Note: The core technology stack is clearly defined as React and TypeScript for frontend development. Proficiency in these is a baseline requirement. Understanding how to integrate with AI models and handle dynamic data streams will be crucial.

👥 Team Culture & Values

Operations Values:

• Innovation & Experimentation: A strong drive to explore new interaction paradigms for AI, encouraging experimentation and pushing creative boundaries.

• User-Centricity: A deep commitment to understanding and serving user needs, ensuring AI interfaces are intuitive, controllable, and trustworthy.

• High Talent Density & Excellence: A value placed on working with and being surrounded by highly skilled individuals who strive for excellence in their craft.

• Agility & Speed: The ability to move quickly, iterate rapidly, and deliver high-quality work in a fast-paced environment.

• Collaboration & Transparency: Open communication, collective decision-making, and a culture where ideas are shared freely across disciplines.

Collaboration Style:

• Cross-Functional Integration: Seamless collaboration between engineering, design, and product teams is essential, with engineers working closely with designers and ML specialists.

• Hands-On & Direct: Team members are expected to be hands-on, taking ownership of tasks and contributing directly to product development.

• Feedback-Rich Environment: Continuous feedback loops are likely in place to facilitate rapid learning and iteration on designs and code.

• Shared Responsibility: A collective approach to problem-solving and decision-making, where everyone contributes to the success of the product.

📝 Enhancement Note: The team culture is geared towards high performers who are passionate about AI and user experience, capable of working collaboratively and independently in a fast-paced startup environment.

⚡ Challenges & Growth Opportunities

Challenges:

• Defining New Interaction Paradigms: The primary challenge is to invent and refine user interfaces for AI where established conventions are scarce, requiring significant creativity and problem-solving.

• Balancing AI Complexity with Simplicity: Making complex AI behavior understandable and controllable for everyday users without oversimplifying or misrepresenting the AI's capabilities.

• Ensuring Trust and Transparency: Designing interfaces that build user trust in AI, clearly communicating its limitations, uncertainties, and decision-making processes.

• Rapid Iteration in Ambiguity: Working effectively with incomplete specifications and rapidly changing requirements inherent in developing cutting-edge AI products.

• Maintaining Performance with Dynamic Data: Ensuring smooth and responsive user experiences when dealing with streaming AI responses and real-time updates.

Learning & Development Opportunities:

• AI HCI Specialization: Become a leader in a niche but rapidly expanding field of AI Human-Computer Interaction.

• Exposure to Advanced AI: Gain firsthand experience with state-of-the-art AI models and their integration into user-facing products.

• Product Development Leadership: Opportunities to influence product strategy and take on leadership roles as the company scales.

• Skill Expansion: Develop expertise in areas like animation, state management, and cross-functional collaboration within a high-talent team.

• Industry Conferences & Training: Support for attending relevant conferences and pursuing certifications in UX, HCI, or frontend engineering.

📝 Enhancement Note: The role presents significant intellectual challenges in a pioneering area of technology, offering substantial growth for ambitious individuals.

💡 Interview Preparation

Strategy Questions:

• Core AI Interaction Design: "Imagine a user is interacting with our AI assistant for a complex, multi-step task (e.g., planning a trip). How would you design the interface to show the AI's progress, handle potential misunderstandings, and allow the user to easily correct or redirect the AI?" (Focus on clarity, control, and feedback loops).

• Rapid Prototyping Approach: "Describe a time you had to build a prototype for an experimental UI concept with limited information. What was your process, what tools did you use, and how did you validate your ideas quickly?" (Highlight speed, iteration, and user feedback).

• Technical Implementation of Dynamic Interfaces: "How would you implement a feature that displays real-time, streaming responses from an AI model in a React application, ensuring a smooth and responsive user experience?" (Assess knowledge of WebSockets, state management, and UI optimization).

Company & Culture Questions:

• Motivation for AI HCI: "What excites you about the intersection of AI and Human-Computer Interaction, and why Bjak specifically?" (Assess passion and alignment with company mission).

• Teamwork in Ambiguity: "How do you collaborate with designers and product managers when requirements are unclear or evolving rapidly, especially when building novel interfaces?" (Evaluate collaboration style and adaptability).

• User-Centric Problem Solving: "Tell me about a time you identified a significant usability issue in an interface and how you addressed it. What was the outcome?" (Gauge UX instincts and problem-solving skills).

Portfolio Presentation Strategy:

• Structure Your Narrative: For each project, clearly outline the problem, your specific role, the design/engineering process, the solution you built, and the outcome or learnings.

• Show, Don't Just Tell: For interactive prototypes, ensure they are easily accessible and demonstrate the key features and interaction patterns you want to highlight.

• Technical Depth: Be prepared to discuss the technical implementation details, trade-offs considered, and why you chose specific technologies or patterns (e.g., React, TypeScript, state management).

• Focus on AI/HCI Relevance: Emphasize projects that showcase your ability to handle complex interactions, dynamic data, user control, and transparency, especially relevant to AI.

• Conciseness: Be mindful of time. Focus on the most impactful projects and articulate your points clearly and efficiently.

📝 Enhancement Note: Interview preparation should focus on demonstrating both strong technical skills in React/TypeScript and a deep understanding of HCI principles as applied to AI. The portfolio is the primary evidence, so practice presenting it effectively.

📌 Application Steps

To apply for this UX Engineer position:

• Submit your application through the provided link on Ashby.

• Curate Your Portfolio: Select 2-3 of your most impactful projects that best showcase your experience in building experimental interfaces, rapid prototyping, and ideally, work related to AI or complex user interactions. Ensure prototypes are functional and easily accessible.

• Tailor Your Resume: Highlight your experience with React, TypeScript, and any projects involving experimental UX, HCI, or AI interfaces. Use keywords from the job description and quantify achievements where possible.

• Prepare Your Portfolio Presentation: Practice walking through your portfolio projects, focusing on the problem, your solution, technical details, and outcomes. Be ready to discuss your design and engineering process, especially in ambiguous situations.

• Research Bjak: Understand their mission and product focus on AI smart assistants. Be prepared to articulate why you are passionate about this specific area and how your skills align with their goals.

⚠️ Important Notice: This enhanced job description includes AI-generated insights and industry-standard assumptions. While every effort has been made to provide a comprehensive overview, applicants should verify all details and expectations directly with Bjak during the application and interview process.