UX Engineer, HCI

Bjak; United States; On-site; USD 90,000 - 120,000; Full time

Job summary

Bjak is looking for a talented individual to develop AI-native product interfaces that users will interact with. This role is not about UI maintenance; instead, it involves prototyping and testing innovative HCI interaction models for AI-driven experiences.

The ideal candidate should possess strong frontend engineering skills in React or TypeScript and a keen sense for product and UX design. Join us at Bjak to help create intelligent user interactions that enhance workflow and technology.

Qualifications

• Strong frontend engineering skills in React or TypeScript.
• Experience with interaction-heavy interfaces.
• Strong product and UX instincts.

Responsibilities

• Build and prototype AI-native product interfaces across web and mobile.
• Create functional prototypes of new HCI interaction models.
• Translate design concepts into working code with attention to usability.

Skills

Frontend engineering skills in React

TypeScript or equivalent

HCI interface design

Prototyping in ambiguous environments

Job description

Company

A1 is building a proactive AI smart assistant for everyday users to bring intelligence to conversations, errands, organising and workflows.

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 behaviour.

Role

You will sit at the intersection of design and engineering, building the AI interfaces that users actually interact with. This is not a UI maintenance role. You will prototype, test, and ship new interaction patterns for AI‑driven experiences where established conventions do not yet exist.

This role is focused on HCI – building interfaces that make AI behaviour understandable, controllable, and useful in real workflows.

What You'll Be Doing

• Build and prototype AI‑native product interfaces across web and mobile.
• Create functional prototypes of new HCI interaction models, including streaming responses, multi‑step task flows, real‑time feedback loops, and system state visibility.
• Translate design concepts into working code with high attention to usability, responsiveness, and motion.
• Experiment with UI patterns that show progress, uncertainty, confidence, failure, and recovery clearly to users.
• Build interfaces that let users supervise, correct, and redirect AI behaviour without micromanaging the system.
• Work closely with product, design, and ML teams to validate interaction ideas quickly.
• Contribute to frontend architecture and reusable UI components for AI product surfaces.
• Identify and fix usability, performance, and state management issues in AI‑driven interfaces.

What You Will Need

• Strong frontend engineering skills in React, TypeScript, or equivalent.
• Experience building interaction‑heavy or experimental interfaces.
• Strong product and UX instincts – you can tell when something is unclear or broken from a user’s perspective.
• Ability to prototype rapidly in ambiguous environments with incomplete specs.
• Understanding of animation, responsiveness, frontend architecture, and UI performance.
• Interest in HCI interfaces and how to design for trust, control, transparency, and recovery.
• Comfort working at the boundary of design and engineering without clear handoffs.
• Ability to move fast while keeping the user experience clear and usable.