Software Engineer, Frontend - AI Agent (TECH-303)

Description

We are a fast-growing legal AI company founded in 2017, with a focus on developing AI-powered legal tech services. Our flagship product is an AI legal platform that covers comprehensive legal tasks, and we have expanded globally with services launched in the US and UK. We are actively challenging new business domains and have recently released a corporate-focused generative AI solution.

Our products leverage cutting-edge machine learning algorithms in natural language processing, large language models (LLMs), and features such as a "legal document graph" and autonomous AI agents to deliver advanced user experiences and sophisticated solutions.

We are creating a brand-new product centered around "AI Agents" to bring about a completely new user experience from scratch. This requires designing interfaces that allow users to naturally interact with AI via natural language to complete complex tasks—not just simple forms or dashboards, but flexible, conversational UIs.

To realize this, we need engineers skilled in modern web frontend technologies and UX design, capable of building advanced, user-centric web interfaces.

If this challenge excites you, let's talk.

---

Responsibilities

As a Web Frontend Engineer for the new AI Agent product, you will:

• Design and develop the web frontend layer of the new AI Agent product.
• Stand between the user and AI to deliver seamless, intuitive experiences.
• Reimagine UX for complex business workflows, leveraging AI’s capability to autonomously understand, supplement, and execute tasks that span multiple tools and information sources.
• Develop sophisticated UI components with HTML/CSS/JavaScript that maximize both usability and aesthetics.
• Collaborate with backend team on architecture.
• Drive enhancements in engineering productivity and organizational effectiveness through automation, improved observability, process refinement, and documentation.
• Mentor and coach other team members as needed.

---

What You’ll Gain

• Opportunity to develop products that fully leverage AI technologies.
• Contribute to the frontend side of challenging and user-friendly UX.
• Direct interaction and collaboration with both business and engineering teams as equal partners working toward one goal.
• Experience high-level decision-making with great responsibility in a rapidly growing company balancing business expansion, technical investment, and technical debt management.

---

Tech Stack

• Frontend: TypeScript, React, React-Router, Vite, In-house Design System

---

Preferred Experiences

• Understanding of specifications/protocols relevant to AI application development (e.g., MCP/A2A/AG-UI).
• Experience building complex GUIs without reliance on UI libraries.
• Web accessibility expertise.
• Knowledge of software architecture.
• Ability to implement quickly and robustly using AI tools such as Coding Agent.
• Improvement of legacy software.
• Performance-oriented design, including network requests and algorithm optimizations.
• Experience handling large-scale frontend projects as a specialist.
• Track record of driving continuous improvement in development teams.
• Skill in writing user-facing copy for clarity.
• Excellent communication skills and the ability to work smoothly with team members of diverse cultural backgrounds (business-level proficiency in Japanese and English required).

---

What We’re Looking For

• Ability to think about "why" and "what" during development and improvement, communicating effectively with stakeholders.
• Flexible mindset, not limited to one’s own areas of expertise, and proactive approach to problem-solving.
• Respectful attitude and willingness to act for the benefit of the team, not just oneself.
• Enthusiasm for learning and growth, with a commitment to ongoing effort.

---

Working Conditions

Salary

• 10,000,000 – 15,000,000 JPY (depending on experience and years)

Location

• Shibuya, Tokyo (full remote work not available)

Job Type

• Full-time, permanent employee

Work Hours

• Flexible hours without core time, or discretionary labor system
• Overtime may be required
• One hour break per day

Probation

• 3 months

Benefits

• 120+ paid holidays per year / complete 2-day weekends / national holidays
• Paid leave on joining, year-end/new year holidays, special leave (sick, work-life balance, birthday, etc.), pre- and post-natal, childcare and caregiving leave, congratulatory or condolence leave
• Language learning support
• Personal development budget
• Flu vaccination support
• No smoking indoors (smoking room in building)
• Side jobs permitted (with approval)
• "Eruboshi" certification (government recognition for promoting women in the workplace)

---