AI Full-stack Engineer

Job Description ■Founding Full Stack Engineer / Tech Lead You will take the lead from the architecture design and technology selection stages. You will shape new areas of rapidly growing businesses and products as an initial member. ■Specific Job Responsibilities ① Sales Enablement AI Agent ・Lead the architecture design and technology selection for the Sales Enablement AI Agent domain from scratch. ・Lead the design and development of AI agent functions that support sales negotiation preparation and review. ・Build the LLM/agent platform (prompt design, RAG, context management, etc.). ・Design and implement the front-end experience transitioned from the global menu. ② Sales Conversation Intelligence ・Lead the architecture design and technology selection for the Sales Conversation Intelligence domain from scratch. ・Design and develop the acquisition and processing pipeline for sales negotiation logs (recordings and voice). ・Build the transcription pipeline using STT (speech recognition). ・Design and develop sales negotiation analysis and task extraction functions utilizing LLM. - Designing data/APIs to link extraction results with BizClo - Designing and implementing the front-end experience accessed through the global menu. - Designing and improving operational aspects, including infrastructure, performance, and reliability. Working Hours 9:00 AM - 6:00 PM (including one-hour break), overtime available, discretionary work system Job Requirements ■Required Skills ・5+ years of practical experience as a software engineer ・Strong full-stack development experience in modern web applications ・Frontend development experience using React/Next.js, etc. ・Backend development experience using Node.js/Python, etc. ・Experience in designing and operating with infrastructure and performance in mind ・Ability to execute architecture design and technology selection from scratch ・Residing in Japan and speaking business-level Japanese ・Experience and willingness to lead a team of 1-2 people ・Ability to proactively drive projects even in highly uncertain situations ■Preferred Skills ・Experience in application development utilizing LLM/AI agents ・Knowledge of RAG, prompt engineering, and dialogue design ・Product development experience in the financial domain or sales support area ・Experience in developing scalable SaaS platforms ・Interest in and practical experience with AI-assisted development workflows such as Claude ・English communication skills ■Desired Candidate Profile ・Ability to formulate hypotheses and move forward even in highly ambiguous situations ・Strong desire to build systems from scratch ・Positive attitude towards training and supporting the growth of team members ・Ability to take responsibility for technical decisions and drive them forward while involving others English Level Business Conversation Level (TOEIC 735-860) Japanese Level Business Level(JLPT Level 2 or N2) Salary JPY 7,000,000 - 11,000,000 yen (Monthly Salary: ¥585,000 - ¥917,000; Basic Salary: ¥432,832 - ¥678,473; Fixed Overtime Pay for 45 hours: ¥152,168 - ¥238,527) Benefits & Perks Commuting Allowance: Paid according to company regulations, transportation expenses paid, bicycle commuting permitted, company-provided laptop, company-provided mobile phone (for some positions only), social insurance, life and health support leave, health checkup cost coverage, childbirth and childcare support system, club activities. Holidays Saturdays, Sundays, public holidays, Year-end and New Year holidays, summer holidays, bereavement leave, paid leave. Job Contract Period Full-time employee with a 3-month trial period. Nearest Station You can choose your work location from either Tokyo or Osaka with a hybrid approach of remote work and in-office work.