• Full-time

Publication date： 2026.06.18

[Flex/Hybrid] AI Engineer

  • R&D / Engineer /Technician (AI, Data)
  • Tokyo
  • Salary： 6 to 15 million yen
【フレックス/ハイブリッド】AIエンジニア
職種Position R&D / Engineer /Technician (AI, Data)
会社概要Company profile We are a "Generative AI-integrated consulting firm" centered on IT consulting and AI development. Beyond standard IT consulting and contract development, we leverage AI agents in our consulting services, develop AI SaaS products, and operate platforms for freelancers. By staying at the forefront of technology and seizing the trends of the times as opportunities, we continuously challenge ourselves to expand the potential of both individuals and organizations. In the generative AI space specifically, we actively support new business planning by engaging subject matter experts as advisors and hosting regular internal study sessions.

Led by a 28-year-old CEO with a Big 4 background, our team comprises a CTO with executive experience at listed companies and major tech ventures, young consultants from firms like the Big 4 and Accenture, and a diverse group of engineers. We have grown to a workforce of 50 employees with an average age of 30.7 and an average annual income exceeding 10 million yen (as of January 2026).
仕事内容Job description The AI ​​team's scope extends far beyond mere model building or Proof of Concept (PoC) projects.

We have established an environment where we define the optimal AI architecture to address deep-seated client challenges identified by our consultants, and then build the actual systems and products for client use from the ground up.

【Specific Responsibilities】
■ Design and development of Generative AI solutions
・Designing application architectures utilizing LLMs, RAG, VLMs, etc.
・Evaluating and improving RAG (Retrieval-Augmented Generation) accuracy; development using frameworks like LangChain.
・Building complex inference logic and multi-agent systems using LangChain, LangGraph, and ADK.
■ Model optimization and evaluation
・Developing hybrid search infrastructure combining vector search (using pgvector) and graph structures (using Neo4j).
・Prompt engineering and fine-tuning for domain-specific adaptation.
・Cleansing domain-specific data and optimizing chunking strategies.
■ Production deployment and LLMOps
・Optimizing inference costs and implementing APIs with a focus on real-time performance.
・Establishing continuous performance monitoring and model retraining workflows.
■ Technology selection and R&D
・Staying abreast of the latest research papers and technological trends (domestic and international) and proposing their rapid integration into products.

【Management Team (Generative AI Division)】
◼️ CAIO (Chief AI Officer)
A multilingual (Japanese, Chinese, Korean, English) Generative AI specialist. After working as an AI engineer at a major tech giant (GAFA)—focusing on areas such as speech processing—he joined Acrosstudio. He excels at optimizing AI for specific tasks through LLM fine-tuning and AI agent development. Recently, he has focused on developing multimodal LLMs and agent memory systems.
◼️ Executive Officer / CTO
Possesses an extensive track record in Agile product development and in establishing or revitalizing technical organizations, including global development hubs. Most recently, serving as CTO for both startups and publicly traded companies, I have led global talent acquisition (including in Japan), engineering management, AI model development, and product planning.

【Key Development Environments, Languages, and Tools (Selected)】
・Infrastructure: AWS, Google Cloud Platform
・Languages: Python (Django, PyTorch); React and NestJS (Frontend); FastAPI (Backend)
・Frameworks: LangChain, LangGraph, ADK (Agent Development Kit)
・Vector DB: pgvector
・Graph DB: neo4j

【Other Environment Details】
・Employees are free to choose between Windows and Mac, though engineers predominantly use Macs.
・US-layout keyboards are available for Macs.
・Access to various AI tools (e.g., ChatGPT, Gemini) is provided at the company's expense.
*All tools utilize the latest models.
・We foster a culture of sharing knowledge on cutting-edge AI and regularly hold AI study sessions.
応募資格Requirement [Must]
・Japanese proficiency equivalent to JLPT N2
・At least 1 year of experience in AI development and implementation

[Preferred]
■ At least 1 year of experience building infrastructure on AWS or Google Cloud Platform
■ At least 1 year of experience in system development
日本語力Japanese level Business
雇用形態Employment type Full-time
勤務エリアLocation Tokyo
勤務時間Working hours Flextime system (core hours: 10:00–15:00)
想定年収Salary 6 to 15 million yen
条件・待遇Condition [Holidays & Leave]
・Holidays: Saturdays, Sundays, and national holidays
・Leave: Annual paid leave (10 days granted after six months of employment); summer, year-end/New Year, and condolence/celebratory leave

[Allowances & Insurance]
・Commuting allowance: Provided in accordance with company policy
・Social insurance: Health insurance, Employees' Pension, workers' compensation insurance, and employment insurance
・Health checkups: Conducted once a year at company expense
・Qualification support system
選考についてProcess Multiple interviews
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