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: 2026-08-22

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

Remote Status: Hybrid

🚀 Role Summary

• This role is focused on defining and designing novel Human-Computer Interaction (HCI) paradigms for AI-native applications, moving beyond traditional UX patterns.

• The Product Designer will be instrumental in creating intuitive interfaces that allow users to understand, guide, and control multi-step AI reasoning and action systems.

• You will be responsible for the end-to-end design process, from conceptualization through to the delivery of user experiences for AI product surfaces.

• Collaboration with Product, Engineering, and Machine Learning teams is key to translating complex AI capabilities into clear, controllable, and trustworthy user journeys for both web and mobile platforms.

📝 Enhancement Note: The job title "Product Designer (UX), HCI" and the description heavily emphasize the Human-Computer Interaction aspect, suggesting a strong focus on the theoretical and practical application of HCI principles to AI systems. The company's mission to build "proactive applications" and "bring intelligence to conversations, errands, organising and workflows, with minimal prompting" indicates a need for designers who can conceptualize and build interfaces for AI that acts autonomously but remains controllable. This role likely requires a deep understanding of user trust, transparency, and control in the context of advanced AI.

📈 Primary Responsibilities

• Design intuitive and user-centric end-to-end user experiences for AI product surfaces, from initial concept through to final product delivery.

• Develop innovative interaction patterns specifically for human-AI workflows, encompassing areas such as prompting, progress review, confirmation, correction, task handoff, and error recovery.

• Create interfaces that clearly communicate the AI's current state, its knowledge base, areas of uncertainty, and anticipated next steps to the user.

• Translate complex, multi-step AI functionalities into user flows that are clear, manageable, and seamlessly integrated into everyday user contexts.

• Partner closely with product managers, engineers, and machine learning specialists to collaboratively define problems, validate design concepts, and ensure rapid, high-quality product iteration.

• Produce comprehensive design deliverables, including wireframes, user flows, interactive prototypes, and high-fidelity mockups suitable for both web and mobile applications.

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

• Contribute to the definition and establishment of reusable HCI design patterns as the product and company design system mature.

📝 Enhancement Note: The responsibilities highlight a specific need for designing "AI-native" interfaces, moving beyond standard UX practices. This implies a focus on how users interact with systems that exhibit agency, predict user needs, and perform multi-step tasks. The emphasis on "understanding what the AI is doing," "trust," and "control" suggests that the role requires not just aesthetic and functional design but also a deep consideration of psychological factors in human-AI collaboration.

🎓 Skills & Qualifications

Education: No specific degree is mandated, but a strong foundation in design principles, HCI, and related fields is implied through the experience and skill requirements.

Experience: Minimum of 2-5 years of experience as a Product Designer or UX Designer, with a demonstrated track record of designing for web or mobile products.

Required Skills:

• Proven experience as a Product Designer or UX Designer with a strong portfolio showcasing work on web or mobile products.

• Expertise in interaction design, focusing on creating intuitive and efficient user journeys.

• Proficient in information hierarchy, ensuring clear and logical organization of content and functionality.

• Strong skills in prototyping, enabling rapid iteration and testing of design concepts.

• High proficiency in Figma, with a demonstrated ability to work within fast-paced iteration workflows.

• Demonstrated ability to simplify complex systems and translate ambiguous product behavior into clear, user-friendly experiences.

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

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

• Sound judgment regarding usability best practices, identification of edge cases, and robust failure handling strategies.

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

• Experience designing for AI-powered products or services.

• Familiarity with Human-Computer Interaction (HCI) research methodologies and principles.

• Experience in developing or contributing to design systems.

• Exposure to user research and usability testing methodologies.

• Understanding of Machine Learning (ML) concepts and their implications for user experience.

📝 Enhancement Note: The "2-5 years" experience level, derived from the AI analysis, indicates a mid-level role. This means candidates are expected to be proficient and largely independent in their design tasks, capable of handling complex problems without constant supervision, but may not yet be at a senior or lead level. The emphasis on "shaping solutions before requirements are fully defined" and "comfort working with ambiguity" is a critical indicator for mid-level roles in innovative tech companies, suggesting a need for proactive problem-solvers.

📊 Process & Systems Portfolio Requirements

Portfolio Essentials:

• A comprehensive portfolio showcasing end-to-end product design projects for web and/or mobile applications.

• Projects should demonstrate strong interaction design, information hierarchy, and clear user flows.

• Evidence of ability to simplify complex systems and translate them into user-friendly interfaces.

• Examples of how you have worked closely with product and engineering teams.

• Case studies that highlight your approach to handling ambiguity and defining solutions.

• Demonstrations of your thought process regarding user trust, control, and transparency in AI-driven experiences. Process Documentation:

• Showcase your design process from problem identification to solution delivery, including user research, ideation, prototyping, and iteration.

• Illustrate your methodology for translating complex AI capabilities into understandable and controllable user experiences.

• Provide examples of how you conduct user research and usability testing to refine designs and identify issues.

• Demonstrate your approach to creating and refining interactive patterns for human-AI workflows.

📝 Enhancement Note: The explicit mention of a portfolio in the interview process description and the AI key skills list strongly suggests that a well-curated portfolio is a mandatory and critical component of the application. For this role, the portfolio should not just showcase visual design but also the strategic thinking behind designing for complex, AI-driven interactions, emphasizing the "how" and "why" behind design decisions, especially concerning trust and control.

💵 Compensation & Benefits

Salary Range: Based on the London location, mid-level (2-5 years experience) Product Designer roles typically range from £50,000 to £75,000 per annum. This estimate considers the competitive tech market in London and the specialized nature of HCI for AI.

Benefits: While specific benefits are not detailed, typical offerings for full-time roles in tech companies in the UK include:

• Comprehensive health insurance (medical, dental, vision).

• Generous paid time off (vacation, sick leave, public holidays).

• Pension scheme contributions.

• Professional development opportunities, including training, conferences, and workshops.

• Potential for stock options or performance-based bonuses.

• Flexible working arrangements as indicated by the hybrid model.

Working Hours: The role is listed as FULL_TIME, with an AI-derived estimate of 40 hours per week. The hybrid work arrangement suggests a balance between in-office collaboration and remote work flexibility.

📝 Enhancement Note: The salary range is an estimate based on industry benchmarks for Product Designers with 2-5 years of experience in London. Actual compensation will depend on the candidate's specific experience, skills, and the company's compensation strategy. The "hybrid" work arrangement implies that candidates should expect to spend a portion of their week in the office, likely for collaborative sessions, team meetings, and design sprints.

🎯 Team & Company Context

🏢 Company Culture

Industry: Technology, specifically focusing on AI-native applications and human-AI interaction. Bjak operates in a rapidly evolving sector aiming to integrate AI into everyday productivity tools.

Company Size: The description "small, world class teams" and "high talent density and hands-on team" suggests a startup or early-stage growth company, likely with under 100 employees. This environment typically fosters rapid decision-making, direct impact, and close collaboration.

Founded: The founding date is not provided, but the mission to build "AI-native" applications for "5 billion users" suggests a relatively new venture focused on a forward-looking market.

Team Structure:

• The operations and design teams are described as "small, world class" and "high talent density."

• Decision-making is collective, and the team emphasizes rapid iteration while maintaining high quality.

• The Product Designer will work closely with Product Managers, Engineers, and Machine Learning teams, indicating a highly cross-functional and collaborative structure.

• The reporting structure is not explicitly defined but is likely flat within a startup environment, potentially reporting to a Head of Product or Design Lead. Methodology:

• Data Analysis & Insights: While not explicitly stated for design, the company's focus on AI and product workflows implies a data-driven approach to understanding user behavior and product performance.

• Workflow Planning & Optimization: The core of the role involves designing and optimizing complex, multi-step AI workflows for user control and clarity.

• Automation & Efficiency: The company's mission is to build proactive AI applications that reduce manual effort and enhance user efficiency, suggesting a strong emphasis on automation and workflow optimization in their product development.

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

📝 Enhancement Note: The company culture is characterized by a fast-paced, hands-on, and collaborative environment typical of innovative tech startups. The emphasis on "high talent density" and "collective decision-making" suggests a team composed of highly skilled individuals who can contribute significantly and work autonomously. The "ActAI" branding within the description hints at a specific focus on actionable and intelligent AI.

📈 Career & Growth Analysis

Operations Career Level: This role is positioned as a mid-level Product Designer (2-5 years of experience) with a specialization in HCI for AI. It offers the opportunity to be at the forefront of designing for a new generation of AI-native applications.

Reporting Structure: While not explicitly detailed, the designer will likely report to a design lead or head of product within a flat organizational structure. They will work closely with cross-functional teams, including product management and engineering.

Operations Impact: The designer will have a direct and significant impact on how users interact with and perceive AI. Their work will shape the usability, trustworthiness, and effectiveness of AI-driven workflows, directly influencing user adoption and satisfaction. Success in this role means defining new standards for human-AI collaboration.

Growth Opportunities:

• Specialization: Deepen expertise in Human-AI Interaction design, becoming a specialist in designing for proactive and multi-step AI systems.

• System Design: Contribute to the development and evolution of the company's design system, establishing reusable HCI patterns for AI.

• Leadership: As the company grows, there will be opportunities to mentor junior designers, lead design initiatives, or potentially move into a senior or lead design role.

• Industry Influence: Contribute to defining best practices in a nascent field of AI-native product design, potentially leading to industry recognition.

📝 Enhancement Note: The growth opportunities highlight the potential for significant career development within a cutting-edge field. The emphasis on defining new interaction models suggests that this role offers a chance to be a pioneer in AI UX, which can be a significant differentiator for future career prospects.

🌐 Work Environment

Office Type: The "Hybrid" work arrangement indicates a mix of remote work and in-office presence. The company likely operates from a modern office space designed to facilitate collaboration, brainstorming, and team cohesion.

Office Location(s): London, England. This implies access to a vibrant tech hub with excellent public transportation and amenities. Specific office address details would be provided upon further engagement.

Workspace Context:

• Collaboration: The environment is designed for close collaboration between product, engineering, ML, and design teams, likely through shared workspaces, meeting rooms, and digital collaboration tools.

• Tools & Technology: Expect access to industry-standard design and collaboration tools, with a strong emphasis on Figma. The company is building AI products, so there may be opportunities to work with AI development tools or platforms.

• Team Interaction: Regular team meetings, design reviews, and cross-functional syncs will be integral to the workflow, fostering a sense of shared purpose and continuous feedback.

Work Schedule: The standard 40-hour work week is expected, with the hybrid model offering flexibility. The fast-paced nature of a startup may sometimes require extended hours during critical project phases, but the focus is on efficient and impactful work.

📝 Enhancement Note: The hybrid model in London offers a balance between the flexibility of remote work and the benefits of in-person collaboration, which is crucial for design and product development. Candidates should be prepared for a dynamic work environment where quick iterations and close team interaction are common.

📄 Application & Portfolio Review Process

Interview Process:

• Application Submission: Candidates must submit a portfolio as part of their initial application. This is a critical screening step.

• Round 1 Interview (Screening/Fit): Likely a virtual meeting to assess overall fit, experience, and initial understanding of the role. May involve a brief discussion of portfolio highlights.

• Round 2 Interview (Deep Dive/Assessment): This will involve a more in-depth discussion of the candidate's portfolio, design process, and problem-solving skills. It may include a take-home design challenge or a live design exercise.

• Design Assessment: A specific design exercise focused on a problem relevant to human-AI interaction or workflow design. This is to evaluate practical skills, critical thinking, and approach to ambiguity.

• Final Interview: Potentially with senior leadership or key stakeholders to discuss strategic fit and long-term vision.

• Decision: A prompt decision is promised, reflecting the company's value for transparency and efficiency.

Portfolio Review Tips:

• Curate Selectively: Showcase 2-4 of your strongest, most relevant projects. Prioritize quality over quantity.

• Tell a Story: For each project, clearly articulate the problem, your role, your process (research, ideation, design decisions, testing), the challenges you faced, and the impact of your solution.

• Highlight AI/HCI Focus: Emphasize projects that demonstrate your ability to design for complex systems, ambiguity, and user trust/control. If you have AI-specific projects, showcase them prominently.

• Showcase Figma Skills: Demonstrate proficiency in Figma through interactive prototypes and well-structured design files.

• Explain Your Process: Clearly articulate your design methodology, especially how you approach user research, iteration, and collaboration with cross-functional teams.

• Address Trust & Control: For AI-related projects, explicitly discuss how you addressed user trust, transparency, and control.

Challenge Preparation:

• Understand the AI Context: Familiarize yourself with current trends in AI, HCI, and the challenges of designing for AI-native applications.

• Practice Problem Decomposition: Be ready to break down complex problems into smaller, manageable parts.

• Focus on Process: The assessment will likely evaluate your thought process, not just the final output. Be prepared to articulate your reasoning.

• Consider Edge Cases & Failure Modes: Think about how users might misuse the AI or how it might fail, and how your design would handle these scenarios.

• Prepare for Ambiguity: Be comfortable working with incomplete information and making reasoned assumptions.

📝 Enhancement Note: The interview process emphasizes a portfolio-driven approach and a practical design assessment, which is common for design roles. Candidates should prepare to not only showcase their past work but also demonstrate their problem-solving skills and strategic thinking in a live or take-home exercise. The focus on AI means a deep dive into HCI principles and how they apply to complex, evolving technologies.

🛠 Tools & Technology Stack

Primary Tools:

• Figma: The primary tool for wireframing, prototyping, and high-fidelity design, with an expectation of proficiency and fast iteration.

• Prototyping Tools: Implied use of Figma's prototyping features or other similar tools for creating interactive user flows.

• Design System Tools: As the design system matures, tools for managing and contributing to it will be essential.

Analytics & Reporting:

• While not explicitly mentioned for design, the company's AI focus suggests that analytics will be crucial. Designers may need to interpret user data from tools like Amplitude, Mixpanel, or Google Analytics to inform design decisions and measure impact.

• Understanding of how to design for trackable user actions and key performance indicators (KPIs) is beneficial. CRM & Automation:

• Not directly applicable to the core design role, but an understanding of how user interactions within the product feed into CRM or automation systems might be beneficial for context.

📝 Enhancement Note: Proficiency in Figma is a non-negotiable requirement. The role also implies a need for designers who can work with tools that facilitate rapid iteration and collaboration. While specific analytics or CRM tools aren't listed for the designer, an awareness of how design choices impact user data and business metrics is increasingly important in product roles.

👥 Team Culture & Values

Operations Values:

• High Talent Density & Hands-on: Expect to work with exceptionally skilled individuals who are deeply involved in their work and contribute actively.

• Collective Decision-Making: While individuals execute independently, key decisions are made collaboratively, valuing diverse perspectives.

• Rapid Speed & High Quality: A balance is struck between shipping quickly and ensuring the quality and robustness of the product.

• Structure & Judgment: While working with ambiguity, there's an expectation to bring structure to problems and exercise sound judgment.

• Execution & Independence: The ability to work autonomously and drive tasks to completion is highly valued.

• Magical Product: A shared ambition to create a truly exceptional and impactful product for users.

Collaboration Style:

• Cross-functional Integration: Design is deeply integrated with Product, Engineering, and ML teams, fostering a holistic approach to product development.

• Process Review & Feedback: A culture that likely encourages open feedback and iterative refinement of designs and processes.

• Knowledge Sharing: Within a small, high-talent team, continuous learning and sharing of insights is crucial for collective growth and innovation.

📝 Enhancement Note: The team values a proactive, independent, and collaborative spirit. Candidates should be comfortable with a startup environment where individual contributions are highly visible and can significantly influence the product's direction. The emphasis on "magical product" suggests a drive for innovation and user delight.

⚡ Challenges & Growth Opportunities

Challenges:

• Designing for Novel AI Interactions: The primary challenge is creating user experiences for AI that go beyond existing paradigms, requiring significant conceptual innovation.

• Building User Trust in AI: Ensuring users feel in control and trust the AI's reasoning and actions, especially in multi-step or complex workflows.

• Handling Ambiguity: Working in a fast-paced startup environment with evolving requirements and defining solutions for undefined problems.

• Balancing AI Capabilities with Usability: Translating powerful but potentially complex AI capabilities into simple, intuitive, and reliable user interfaces.

• Rapid Iteration and Learning: Continuously testing, learning, and iterating on designs in a fast-moving product development cycle.

Learning & Development Opportunities:

• Cutting-Edge Field: Opportunity to become a pioneer in designing for AI-native applications and HCI for advanced AI systems.

• Skill Specialization: Develop deep expertise in designing for AI, proactive systems, and complex human-AI collaboration.

• Cross-functional Learning: Gain exposure to product strategy, engineering challenges, and ML principles through close collaboration.

• Design System Contribution: Play a key role in shaping the company's design system and establishing new HCI patterns.

• Industry Exposure: Potential to attend relevant conferences or workshops focused on AI, UX, and HCI.

📝 Enhancement Note: The challenges are directly tied to the innovative nature of the company's mission. Success will require a blend of strong design fundamentals and a willingness to explore uncharted territory in human-AI interaction. The growth opportunities are substantial for individuals looking to make a significant impact in a rapidly evolving technological landscape.

💡 Interview Preparation

Strategy Questions:

• "Describe a time you had to design for a complex system with ambiguous requirements. How did you approach it, and what was the outcome?" (Focus on your process for handling ambiguity and structuring problems.)

• "How would you design an interface for an AI that performs multi-step tasks, ensuring the user understands its progress and can intervene if necessary?" (Prepare a conceptual approach, considering trust, control, and transparency.)

• "Walk me through a project in your portfolio where you had to simplify a complex user flow. What was your process, and what were the key design decisions?" (Be ready to articulate your design rationale and problem-solving steps.) Company & Culture Questions:

• "What excites you about designing for AI-native applications, and what do you see as the biggest challenges in this space?" (Show your understanding of the field and your passion.)

• "How do you approach collaboration with product managers and engineers, especially in a fast-paced environment?" (Highlight your teamwork and communication skills.)

• "Describe your understanding of user trust and control in AI systems. How would you incorporate these principles into your design work?" (Demonstrate your awareness of critical HCI aspects for AI.) Portfolio Presentation Strategy:

• Start with the Problem: Clearly define the user problem or business objective your project addressed.

• Your Role & Contribution: Specify your exact role and responsibilities within the team.

• Design Process Walkthrough: Detail your methodology step-by-step, including research, ideation, wireframing, prototyping, testing, and iteration. Use visual aids effectively.

• Key Design Decisions: Explain the rationale behind your most critical design choices, especially those related to interaction patterns, information hierarchy, and addressing AI-specific challenges.

• Impact & Metrics: Quantify the impact of your design where possible (e.g., improved conversion rates, reduced errors, increased user satisfaction). If quantitative data isn't available, discuss qualitative feedback and observed user behavior.

• AI/HCI Focus: For relevant projects, specifically address how you considered user trust, control, transparency, and the unique challenges of human-AI interaction.

📝 Enhancement Note: Interview preparation for this role should heavily lean into demonstrating an understanding of HCI principles applied to AI. Candidates must be ready to articulate their design process, justify their decisions, and showcase how they handle complexity and ambiguity. The portfolio presentation is not just about showing pretty pictures but telling a compelling story about problem-solving and impact.

📌 Application Steps

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

• Submit your application through the provided Ashby link.

• Portfolio Customization: Ensure your portfolio is updated and prominently features projects demonstrating strong UX/UI design skills for web and mobile, with a particular emphasis on complex systems, interaction design, and ideally, any experience with AI or novel technology interfaces. Tailor your portfolio's narrative to highlight your ability to design for ambiguity and user trust/control.

• Resume Optimization: Craft your resume to clearly highlight your years of experience, proficiency in Figma, and specific skills in interaction design, prototyping, and user research. Use keywords from the job description such as "HCI," "AI," "Interaction Design," and "Proactive AI."

• Interview Preparation: Thoroughly review your portfolio projects and prepare to discuss your design process, decision-making rationale, and the impact of your work. Practice articulating your approach to designing for AI, focusing on user trust, control, and transparency. Be ready for a design assessment.

• Company Research: Familiarize yourself with Bjak's mission and "ActAI" focus. Understand their goal of building AI-native applications and how this role contributes to that vision. Research current trends in HCI for AI to be prepared for strategic discussions.

⚠️ 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.