# Interaction Designer, HCI [Bjak](https://gurify.com/jobs?q=Bjak) · United Kingdom · Posted 4 months ago [Apply on the original posting → (opens in a new tab)](https://jobs.ashbyhq.com/bjakcareer/1546b14d-6bd3-4bb2-acd2-a36a11856b1e) ## Job description ### ABOUT A1 There are over 5 billion users using basic applications today such email, notes, tasks that are not AI-native. Our mission is to build a proactive smart assistant for everyday users to bring intelligence to conversations, errands, organising and workflows, with minimal prompting. Our product focuses on achieving high reliability for long-running workflows, persistent context, and real-world task completion. The system must handle multi-step reasoning, interact with external tools, and remain reliable despite non-deterministic model behavior. Our objective is to help users complete tasks daily enjoyable with over ~90%* reduced time. ### ROLE You will design the detailed mechanics of how users interact with A1 - the gestures, states, flows, and micro-decisions that determine whether an AI-driven product feels controlled or confusing. This role is focused on HCI interaction design: how users give input, receive feedback, supervise AI actions, correct mistakes, and maintain agency over AI-driven workflows. There are no established playbooks for interaction design in proactive AI products. You will help define new patterns from the ground up. ### WHAT YOU'LL BE DOING - Design detailed interaction models for AI-driven flows, including how users initiate, monitor, pause, correct, and complete multi-step tasks. - Define interaction states for AI interfaces: idle, thinking, acting, waiting, uncertain, interrupted, failed, and recovered. - Design human-in-the-loop controls - how users review AI decisions, override actions, and stay informed without micromanaging. - Create interaction patterns for delegation, approval, correction, escalation, reversibility, and recovery. - Create detailed interaction specifications, annotated flows, and prototypes for engineering handoff. - Work with product and ML teams to translate system capabilities and constraints into usable interaction patterns. - Test interaction designs with real users to identify where AI behavior creates confusion, distrust, or friction. - Contribute to a shared library of HCI interaction patterns that can be reused across the product. ### WHAT YOU WILL NEED - Experience as an interaction designer or senior UX designer with strong interaction design depth. - Ability to design at the micro level - states, transitions, edge cases, and failure handling. - Strong prototyping skills in Figma or equivalent tools. - Systematic thinking - able to map complex AI behavior into coherent user-facing interaction logic. - Clear understanding of HCI principles: user control, transparency, feedback, and graceful recovery. - Experience working closely with engineers to ensure interactions are implemented as designed. - Comfort designing for systems where output is non-deterministic and behavior can vary across sessions. - Strong judgment on when users should be guided, interrupted, asked for confirmation, or left alone. ### HOW WE WORK The best products today in the world were built by small, world class teams. We are a high talent density and hands-on team. We make decisions collectively, move at rapid speed, striking a balance between shipping high quality work and learning. Joining our team requires the ability to bring structure, exercise judgment, and execute independently. Our goal is to put in hands of our users a truly magical product ### INTERVIEW PROCESS For design roles, we expect candidates to submit a portfolio as part of the application process. If there appears to be a fit, we'll reach out to schedule 2 rounds of interviews and a design assessment. Applications are evaluated by our team members. Interviews will be conducted via virtual meetings and/or onsite. We value transparency and efficiency, so expect a prompt decision. If you've demonstrated the exceptional skills and mindset we're looking for, we'll extend an offer to join us. This isn't just a job offer; it's an invitation to be part of a team that's bringing AI to have practical benefits to billions globally. **Live in Bjak’s hiring system.** Read from the company's own applicant tracking system, not reposted from a job board — so it's a real, open requisition rather than an ad that outlived the role. We remove it as soon as it disappears at source. ## More jobs like this - BJ [Product Designer (UX), HCI](https://gurify.com/job/product-designer-ux-hci-at-bjak-c5b4f07a1c36) Bjak · United Kingdom · 4 weeks ago - BJ [Lead UX Designer](https://gurify.com/job/lead-ux-designer-at-bjak-766efc970982) Bjak · United Kingdom · 4 weeks ago - BJ [Lead UX Designer](https://gurify.com/job/lead-ux-designer-at-bjak-99dc6ce24b4c) Bjak · United Kingdom · 4 weeks ago - BJ [UX Designer](https://gurify.com/job/ux-designer-at-bjak-53c021b9e42c) Bjak · United Kingdom · 7 weeks ago - BJ [Engineering Manager - Stock Trading App](https://gurify.com/job/engineering-manager-stock-trading-app-at-bjak-4698b3347c59) Bjak · United Kingdom · 2 weeks ago - BJ [UX Designer](https://gurify.com/job/ux-designer-at-bjak-e743ec18d4e0) Bjak · United Kingdom · 7 weeks ago ```json {"@context":"https://schema.org/","@type":"JobPosting","title":"Interaction Designer, HCI","description":"\u003Ch3\u003EABOUT A1\u003C/h3\u003E\u003Cp\u003EThere are over 5 billion users using basic applications today such email, notes, tasks that are not AI-native. Our mission is to build a proactive smart assistant for everyday users to bring intelligence to conversations, errands, organising and workflows, with minimal prompting.\u003C/p\u003E\u003Cp\u003EOur product focuses on achieving high reliability for long-running workflows, persistent context, and real-world task completion. The system must handle multi-step reasoning, interact with external tools, and remain reliable despite non-deterministic model behavior. Our objective is to help users complete tasks daily enjoyable with over ~90%* reduced time.\u003C/p\u003E\u003Ch3\u003EROLE\u003C/h3\u003E\u003Cp\u003EYou will design the detailed mechanics of how users interact with A1 - the gestures, states, flows, and micro-decisions that determine whether an AI-driven product feels controlled or confusing.\u003C/p\u003E\u003Cp\u003EThis role is focused on HCI interaction design: how users give input, receive feedback, supervise AI actions, correct mistakes, and maintain agency over AI-driven workflows.\u003C/p\u003E\u003Cp\u003EThere are no established playbooks for interaction design in proactive AI products. You will help define new patterns from the ground up.\u003C/p\u003E\u003Ch3\u003EWHAT YOU\u0026#39;LL BE DOING\u003C/h3\u003E\u003Cul\u003E\u003Cli\u003EDesign detailed interaction models for AI-driven flows, including how users initiate, monitor, pause, correct, and complete multi-step tasks.\u003C/li\u003E\u003C/ul\u003E\u003Cul\u003E\u003Cli\u003EDefine interaction states for AI interfaces: idle, thinking, acting, waiting, uncertain, interrupted, failed, and recovered.\u003C/li\u003E\u003C/ul\u003E\u003Cul\u003E\u003Cli\u003EDesign human-in-the-loop controls - how users review AI decisions, override actions, and stay informed without micromanaging.\u003C/li\u003E\u003C/ul\u003E\u003Cul\u003E\u003Cli\u003ECreate interaction patterns for delegation, approval, correction, escalation, reversibility, and recovery.\u003C/li\u003E\u003C/ul\u003E\u003Cul\u003E\u003Cli\u003ECreate detailed interaction specifications, annotated flows, and prototypes for engineering handoff.\u003C/li\u003E\u003C/ul\u003E\u003Cul\u003E\u003Cli\u003EWork with product and ML teams to translate system capabilities and constraints into usable interaction patterns.\u003C/li\u003E\u003C/ul\u003E\u003Cul\u003E\u003Cli\u003ETest interaction designs with real users to identify where AI behavior creates confusion, distrust, or friction.\u003C/li\u003E\u003C/ul\u003E\u003Cul\u003E\u003Cli\u003EContribute to a shared library of HCI interaction patterns that can be reused across the product.\u003C/li\u003E\u003C/ul\u003E\u003Ch3\u003EWHAT YOU WILL NEED\u003C/h3\u003E\u003Cul\u003E\u003Cli\u003EExperience as an interaction designer or senior UX designer with strong interaction design depth.\u003C/li\u003E\u003C/ul\u003E\u003Cul\u003E\u003Cli\u003EAbility to design at the micro level - states, transitions, edge cases, and failure handling.\u003C/li\u003E\u003C/ul\u003E\u003Cul\u003E\u003Cli\u003EStrong prototyping skills in Figma or equivalent tools.\u003C/li\u003E\u003C/ul\u003E\u003Cul\u003E\u003Cli\u003ESystematic thinking - able to map complex AI behavior into coherent user-facing interaction logic.\u003C/li\u003E\u003C/ul\u003E\u003Cul\u003E\u003Cli\u003EClear understanding of HCI principles: user control, transparency, feedback, and graceful recovery.\u003C/li\u003E\u003C/ul\u003E\u003Cul\u003E\u003Cli\u003EExperience working closely with engineers to ensure interactions are implemented as designed.\u003C/li\u003E\u003C/ul\u003E\u003Cul\u003E\u003Cli\u003EComfort designing for systems where output is non-deterministic and behavior can vary across sessions.\u003C/li\u003E\u003C/ul\u003E\u003Cul\u003E\u003Cli\u003EStrong judgment on when users should be guided, interrupted, asked for confirmation, or left alone.\u003C/li\u003E\u003C/ul\u003E\u003Ch3\u003EHOW WE WORK\u003C/h3\u003E\u003Cp\u003EThe best products today in the world were built by small, world class teams. 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