Product Designer (UX), HCI

📍 Job Overview

Job Title: Product Designer (UX), HCI

Company: Bjak

Location: London, England, United Kingdom

Job Type: FULL_TIME

Category: Product Design / UX / HCI

Date Posted: 2026-08-02

Experience Level: 2-5 Years

Remote Status: Hybrid

🚀 Role Summary

• Design cutting-edge Human-Computer Interaction (HCI) interfaces that enable users to effectively understand, guide, and control sophisticated AI systems.

• Develop novel interaction models for proactive AI products, focusing on user comprehension, control, and trust-building within multi-step reasoning workflows.

• Collaborate closely with Product, Engineering, and Machine Learning (ML) teams to translate complex AI capabilities into intuitive and reliable user experiences for both web and mobile platforms.

• Drive the end-to-end design process for AI product surfaces, from conceptualization and wireframing through to high-fidelity prototyping and user research.

📝 Enhancement Note: This role sits at the intersection of AI and UX design, requiring a deep understanding of HCI principles to create intuitive interfaces for complex, proactive AI systems. The emphasis on "minimal prompting" and "proactive smart assistant" suggests a focus on AI that anticipates user needs and initiates actions, demanding innovative design solutions beyond traditional UX patterns.

📈 Primary Responsibilities

• Design end-to-end user experiences for AI product surfaces, encompassing conceptualization, wireframing, user flows, prototyping, and high-fidelity design for both web and mobile applications.

• Craft intuitive interaction patterns for human-AI collaboration, including effective prompting strategies, clear review and confirmation mechanisms, seamless correction workflows, and robust error recovery processes.

• Develop interfaces that provide users with clear insights into the AI's current state, its knowledge base, areas of uncertainty, and upcoming actions, fostering transparency and trust.

• Translate complex, multi-step AI capabilities into user-friendly flows that are easily controllable and applicable to everyday user contexts, reducing cognitive load.

• Actively partner with product managers, engineers, and machine learning specialists to define design problems, iterate on solutions, and ensure rapid, high-quality product delivery.

• Conduct lightweight user research and usability testing to proactively identify user friction points, potential trust issues, and critical failure modes within AI interactions.

• Contribute to the development and maintenance of a reusable HCI design pattern library, ensuring consistency and scalability as the product and design system evolve.

📝 Enhancement Note: The responsibilities highlight a strong emphasis on defining new interaction paradigms for AI. The expectation to "help define new interaction models" and "produce wireframes, flows, prototypes, and high-fidelity designs" indicates a hands-on design role with significant creative ownership. The need to "run lightweight user research and usability tests" suggests a data-informed design approach.

🎓 Skills & Qualifications

Education: Bachelor's degree in Human-Computer Interaction (HCI), Interaction Design, Graphic Design, Computer Science with a design focus, or a related field, or equivalent practical experience.

Experience: 2-5 years of experience in product design or UX design, with a demonstrable portfolio showcasing successful web and mobile product design projects.

Required Skills:

• Proven experience in end-to-end product design, from concept to launch, with a focus on user-centered design principles.

• Strong proficiency in interaction design, information hierarchy, and creating functional prototypes.

• Expert-level skills in Figma for rapid iteration, design system development, and collaborative design workflows.

• Demonstrated ability to distill complex AI functionalities and ambiguous requirements into clear, intuitive, and controllable user experiences.

• Experience collaborating effectively with product managers and engineers in fast-paced, agile team environments.

• Comfort and aptitude for working with ambiguity, and proactively shaping solutions when requirements are not fully defined.

• Sound judgment regarding usability, edge cases, and designing for failure handling in complex systems.

• Clear understanding and articulation of principles related to trust, control, feedback mechanisms, and transparency in AI-driven user experiences. Preferred Skills:

• Experience designing for AI-powered products or systems, particularly those involving multi-step reasoning or proactive assistance.

• Familiarity with machine learning concepts and their implications for user interface design.

• Experience with user research methodologies beyond usability testing, such as contextual inquiry or user interviews.

• Knowledge of design systems and experience contributing to their growth and maintenance.

• Familiarity with front-end development principles to facilitate better collaboration with engineering teams.

📝 Enhancement Note: The experience requirement of "2-5 years" and the specific mention of "simplifying complex systems" and "comfort working with ambiguity" suggest this role is suitable for a mid-level designer ready to tackle novel challenges in AI product design. The emphasis on "trust, control, feedback, and transparency" points to a need for designers who can think critically about the ethical and user-centric implications of AI.

📊 Process & Systems Portfolio Requirements

Portfolio Essentials:

• A curated portfolio demonstrating end-to-end product design projects for web and mobile applications, with a strong emphasis on interaction design and user flow clarity.

• Case studies should clearly articulate the problem, your design process, the solutions implemented, and the measurable impact or learnings derived from user testing and product outcomes.

• Showcase examples of how you translated complex functionalities into intuitive user interfaces, particularly highlighting challenges related to AI or sophisticated systems.

• Include prototypes that effectively communicate interaction logic and user flows, demonstrating your proficiency with tools like Figma. Process Documentation:

• For each case study, clearly outline your design methodology, including user research, ideation, prototyping, and iteration phases.

• Detail your collaboration process with product managers, engineers, and ML teams, providing examples of how you incorporated feedback and technical constraints into your designs.

• Demonstrate your approach to testing and validating designs, including insights gained from usability tests and how they informed design decisions.

• Highlight your ability to define and document interaction patterns, especially those relevant to human-AI workflows, and how these contribute to a cohesive user experience.

📝 Enhancement Note: Given the role's focus on AI and novel interaction patterns, the portfolio should ideally showcase projects that tackle complexity, ambiguity, and user trust. The ability to articulate the "why" behind design decisions, especially in the context of AI, will be crucial. Demonstrating experience with iterative design based on user feedback is also a key requirement.

💵 Compensation & Benefits

Salary Range: For a Product Designer (UX), HCI role with 2-5 years of experience in London, UK, the estimated annual salary range is £55,000 - £75,000. This range is based on industry benchmarks for similar roles in London, considering the specialized nature of AI/HCI design and the company's focus on innovation.

Benefits:

• Comprehensive health insurance coverage, including medical, dental, and vision.

• Generous paid time off (PTO) and public holiday allowance.

• Pension scheme contributions.

• Professional development budget for conferences, courses, and training relevant to UX, HCI, and AI design.

• Opportunities for stock options or equity, reflecting the startup environment and potential for growth.

• Hybrid work model, offering flexibility between remote work and in-office collaboration.

• Access to cutting-edge AI tools and technologies for design and development.

Working Hours: The standard working hours are approximately 40 hours per week. While a hybrid model is in place, flexibility is offered to accommodate project deadlines and team collaboration needs, aligning with the fast-paced nature of the company.

📝 Enhancement Note: The salary estimate is based on data from reputable UK salary aggregators and industry reports for UX/Product Designers in London with 2-5 years of experience. The specific range accounts for the specialized HCI/AI focus, which can command a premium. Benefits are typical for tech startups in London offering competitive packages.

🎯 Team & Company Context

🏢 Company Culture

Industry: Technology / Artificial Intelligence / Software Development. Bjak operates within the rapidly evolving AI sector, aiming to integrate intelligence into everyday applications and workflows, reducing time and effort for users. The company is focused on building reliable, AI-native applications.

Company Size: The description "small, world-class teams" and "high talent density" suggests a lean, agile organization, likely in the startup or early-stage growth phase, with an employee count potentially between 20-100 individuals. This size fosters close collaboration and rapid decision-making.

Founded: Information on the exact founding date is not provided, but the company's mission to build "AI-native" applications implies a relatively recent establishment or a significant pivot towards AI development.

Team Structure:

• The Product Design team is likely small and integrated closely with Product Management, Engineering, and Machine Learning (ML) specialists.

• Reporting structure is probably flat, with designers working directly with product leads and engineering managers, fostering direct communication and quick feedback loops.

• Cross-functional collaboration is a core tenet, with designers expected to work hand-in-hand with technical teams to bring AI concepts to life. Methodology:

• Data analysis and insights are crucial, driving design decisions through user research and usability testing.

• Workflow planning and optimization are central to creating efficient AI interactions.

• Automation and efficiency practices are inherent to the AI product's nature and the company's operational goals.

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

📝 Enhancement Note: The emphasis on "high talent density" and "small, world-class teams" indicates a culture that values expertise, autonomy, and rapid execution. This environment is ideal for individuals who thrive in fast-paced settings and enjoy deep collaboration with highly skilled peers.

📈 Career & Growth Analysis

Operations Career Level: This Product Designer (UX), HCI role is positioned at a mid-level, requiring 2-5 years of experience. It offers the opportunity to move beyond executing defined tasks to shaping new product directions and interaction paradigms within the AI space.

Reporting Structure: Designers are expected to report to a Head of Product or Design Lead, while working very closely with Product Managers and Engineering Leads on a daily basis. This structure ensures alignment and facilitates rapid iteration cycles.

Operations Impact: The designer's work will directly influence the usability, adoption, and perceived intelligence of the AI product. By creating intuitive human-AI workflows, the role has a significant impact on user efficiency, task completion rates, and overall user satisfaction, directly contributing to the product's success and market differentiation.

Growth Opportunities:

• Specialization: Deepen expertise in AI/HCI design, becoming a go-to person for complex AI interactions and user trust mechanisms.

• Leadership: Progress to a Senior Product Designer role, taking on larger projects, mentoring junior designers, and contributing more heavily to product strategy and design system evolution.

• Skill Development: Continuous learning through exposure to cutting-edge ML technologies, advanced prototyping techniques, and user research methods specific to AI. Opportunities for attending industry conferences and workshops.

📝 Enhancement Note: The role is framed as an opportunity to "define new interaction models," suggesting significant potential for impact and growth in a nascent field. The company's small size and focus on "high talent density" imply that high performers can quickly advance and gain significant responsibility.

🌐 Work Environment

Office Type: The company operates on a hybrid model. This implies a mix of remote work and in-office presence, likely for collaborative sessions, team meetings, and focused work periods. The office environment is expected to be modern and conducive to collaboration.

Office Location(s): Primarily based in London, England, United Kingdom, with the expectation of some in-office days for team synergy and collaboration.

Workspace Context:

• The workspace is designed to foster collaboration, with opportunities for direct interaction with product managers, engineers, and ML specialists.

• Access to modern design tools and technology, including Figma and potentially other prototyping or research platforms, will be readily available.

• An environment that encourages open communication, idea sharing, and rapid iteration, supporting the company's fast-paced development ethos.

Work Schedule: A standard 40-hour work week is expected, with the hybrid model offering flexibility. This schedule allows for dedicated time for focused design work, user research, and team synchronization, balancing individual productivity with collaborative needs.

📝 Enhancement Note: The hybrid model in London suggests a professional office environment combined with the flexibility of remote work. The emphasis on collaboration indicates that in-office days will likely be structured around team activities and cross-functional meetings.

📄 Application & Portfolio Review Process

Interview Process:

• Application Submission: Submit your resume and a portfolio as the initial step. The portfolio is critical for demonstrating your UX/HCI design skills.

• Initial Screening: Based on your application and portfolio, the team will assess your fit for the role.

• Round 1 Interview: Typically a virtual meeting with a Product Manager or Senior Designer to discuss your background, experience, and design philosophy.

• Design Assessment: A practical design exercise, likely focused on a hypothetical AI interaction challenge. This assesses your problem-solving skills, design process, and ability to articulate solutions.

• Round 2 Interview: A virtual or onsite meeting with multiple team members (e.g., Head of Product, Engineering Lead, fellow designers) to delve deeper into your experience, collaboration style, and cultural fit. This may include a portfolio walkthrough.

• Final Evaluation: Prompt decision based on demonstrated skills, mindset, and cultural alignment.

Portfolio Review Tips:

• Highlight AI/Complex Systems: Prioritize projects that showcase your ability to design for complexity, ambiguity, and user trust, especially if they involve AI or sophisticated systems.

• Structure Your Case Studies: Clearly articulate the problem, your role, the design process (research, ideation, prototyping, testing), your solutions, and the outcomes or learnings. Use visuals effectively.

• Demonstrate Interaction Design: Showcase interactive prototypes that clearly illustrate user flows and interaction patterns.

• Focus on HCI Principles: Explicitly discuss how your designs apply HCI principles, particularly concerning control, feedback, and transparency in AI interactions.

• Tailor to the Role: Emphasize skills and projects most relevant to designing for AI-driven workflows and proactive assistants.

Challenge Preparation:

• Understand the Core Problem: Be prepared to address challenges related to user control, understanding AI behavior, building trust, and managing AI errors.

• Articulate Your Process: Be ready to explain your design process step-by-step, justifying your decisions with user-centered rationale and HCI best practices.

• Think About AI Specifics: Consider how AI's probabilistic nature, learning capabilities, and potential for unexpected behavior impact UX. Focus on clarity, predictability, and user agency.

• Prepare Questions: Have thoughtful questions ready about the product, the team, the AI technology, and the company's vision for human-AI interaction.

📝 Enhancement Note: The emphasis on a "design assessment" and "portfolio walkthrough" indicates that practical design skills and the ability to articulate one's process are paramount. Candidates should be prepared to discuss their thinking deeply, especially concerning the unique challenges of designing for AI.

🛠 Tools & Technology Stack

Primary Tools:

• Figma: The core design tool for wireframing, prototyping, high-fidelity design, and collaboration. Proficiency is essential for rapid iteration and design system management.

• Prototyping Tools: Beyond Figma, familiarity with other advanced prototyping tools for complex interactions or user testing may be beneficial.

• User Research Platforms: Experience with tools for conducting usability tests, remote user interviews, and surveys (e.g., UserTesting.com, Maze, Typeform).

Analytics & Reporting:

• While not directly a designer's primary tool, understanding how to interpret user behavior analytics (e.g., from Amplitude, Mixpanel) to inform design decisions is valuable. CRM & Automation:

• Not directly applicable to this design role, but an understanding of how design integrates with product development workflows and potentially CRM-driven user journeys can be advantageous.

📝 Enhancement Note: Figma is explicitly mentioned as a required proficiency. The role implies a need for designers who are not only skilled in visual and interaction design but also adept at using modern design tools for efficient collaboration and iteration within a fast-paced tech environment.

👥 Team Culture & Values

Operations Values:

• High Talent Density & Execution: A culture that values expertise, autonomy, and the ability to deliver high-quality work rapidly.

• Collective Decision-Making & Speed: Decisions are made collaboratively but with a focus on moving quickly to iterate and ship products.

• User-Centricity & AI Innovation: A commitment to building "truly magical products" that offer practical AI benefits, grounded in understanding user needs and pushing the boundaries of HCI.

• Data-Driven Approach: Design decisions are informed by user research and data to ensure effectiveness and reliability.

• Ambiguity & Judgment: An environment where individuals are expected to exercise good judgment and bring structure to undefined problems.

Collaboration Style:

• Deep Cross-Functional Integration: Designers work intimately with Product, Engineering, and ML teams, fostering a shared understanding and collective ownership of product development.

• Iterative Feedback Loops: A culture of continuous feedback and rapid iteration is central to how the team operates, ensuring designs are constantly refined.

• Knowledge Sharing: While not explicitly stated, a "high talent density" team typically encourages informal knowledge sharing and peer learning.

📝 Enhancement Note: The company culture emphasizes a blend of high performance, rapid execution, and collaborative problem-solving. Designers are expected to be proactive, autonomous, and adept at working within a team of experts. The "truly magical product" aspiration suggests a drive for innovation and exceptional user experiences.

⚡ Challenges & Growth Opportunities

Challenges:

• Designing for AI Ambiguity: Creating intuitive interfaces for systems that are inherently complex, probabilistic, and may exhibit non-deterministic behavior. This requires designing for trust, transparency, and control in novel ways.

• Defining New Interaction Paradigms: Moving beyond established UX patterns to invent new ways users interact with proactive AI assistants, requiring significant creativity and user empathy.

• Balancing Speed and Quality: Working in a fast-paced environment while ensuring high-quality, reliable, and user-friendly AI experiences.

• Cross-functional Alignment: Ensuring clear communication and shared understanding of AI capabilities and limitations across design, product, and engineering teams.

Learning & Development Opportunities:

• AI/HCI Specialization: Deepen expertise in the rapidly evolving field of AI-driven user interfaces and human-AI interaction.

• Product Strategy Involvement: Gain exposure to product strategy and roadmap planning for innovative AI products.

• Mentorship: Learn from experienced professionals in a "high talent density" environment, potentially leading to mentorship opportunities as the designer grows.

• Industry Exposure: Opportunity to work with cutting-edge AI technologies and potentially attend relevant industry conferences.

📝 Enhancement Note: The primary challenge lies in pioneering new design solutions for AI, an area with few established best practices. This presents a significant growth opportunity for designers eager to shape the future of human-computer interaction.

💡 Interview Preparation

Strategy Questions:

• "How would you design an interface for an AI that proactively suggests actions to a user, and what are the key considerations for user trust and control?" (Focus on interaction patterns, feedback mechanisms, and error handling).

• "Describe a time you had to simplify a complex technical system into a user-friendly experience. What was your process, and what were the outcomes?" (Highlight your design process, problem-solving skills, and ability to translate technical concepts).

• "How do you approach designing for ambiguity, especially when user requirements are not fully defined?" (Showcase your comfort with uncertainty, iterative design, and proactive problem-solving). Company & Culture Questions:

• "What interests you most about designing for AI products at Bjak, given our mission to build proactive smart assistants?" (Demonstrate your understanding of the company's mission and your passion for AI/HCI).

• "How do you envision collaborating with ML engineers and product managers to ensure the AI's capabilities are effectively translated into user experiences?" (Discuss your cross-functional collaboration style and communication strategies).

• "How do you measure the success of a user experience, particularly in the context of AI interactions where traditional metrics might not apply?" (Focus on user satisfaction, task completion, trust, and efficiency). Portfolio Presentation Strategy:

• Tell a Story: For each case study, frame it as a narrative: the challenge, your journey, the solution, and the impact.

• Focus on "Why": Clearly explain the rationale behind your design decisions, linking them to user needs, HCI principles, and business goals.

• Show, Don't Just Tell: Use prototypes and visuals to demonstrate interaction flows and user experience. Be prepared to walk through your Figma files or interactive prototypes.

• Highlight AI/Complexity: Emphasize projects that demonstrate your ability to handle complex systems and novel interaction challenges, especially those related to AI or user trust.

• Be Ready for Q&A: Anticipate questions about your process, decisions, and potential alternative solutions.

📝 Enhancement Note: Interview preparation should focus on demonstrating a deep understanding of HCI principles as applied to AI, a strong, iterative design process, and the ability to collaborate effectively in a fast-paced, innovative environment. The portfolio is the primary tool for showcasing these capabilities.

📌 Application Steps

To apply for this Product Designer (UX), HCI position:

• Submit your application through the provided link, ensuring you include your resume and a link to your online portfolio.

• Portfolio Customization: Tailor your portfolio to highlight projects that best demonstrate your experience in interaction design, UX for web/mobile, and any relevant work with complex systems or AI. Emphasize case studies that showcase your design process and problem-solving skills.

• Resume Optimization: Ensure your resume clearly articulates your years of experience, key skills in UX/HCI/Figma, and quantifiable achievements where possible. Use keywords from the job description.

• Interview Preparation: Practice articulating your design process, rationale, and project outcomes. Prepare to discuss your approach to designing for AI, user trust, and collaboration. Review common UX interview questions and prepare your own insightful questions for the interviewers.

• Company Research: Familiarize yourself with Bjak's mission, values, and the broader AI landscape they operate in. Understand their focus on proactive AI and everyday applications.

⚠️ Important Notice: This enhanced job description includes AI-generated insights and operations industry-standard assumptions. All details should be verified directly with the hiring organization before making application decisions.

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