RECRUIT
Recruitment
Job Overview
Recruitment Overview
Yoimaru LLC is an IT venture company that supports DX promotion for companies and local governments under the vision of “Realizing Local Creation through the Power of IT.”
For this position, we are seeking an AI Engineer who can design and implement generative AI / LLM solutions by integrating them into business systems and workflows in a way that can withstand real-world operations.
At Yoimaru, the AI Engineer role is not primarily focused on researching or training machine learning models. Instead, this role focuses on engineering AI systems that meet business requirements, mainly through RAG (Retrieval-Augmented Generation) design and prompt engineering.
Role Description
- Design and implementation of business support systems using generative AI
- Design of RAG architecture
– Selection and preprocessing of data sources
– Design of vectorization and retrieval methods
– Design of answer generation flows and output structures Prompt design and improvement - Prompt design and improvement
– Instruction design based on business requirements
– Development of output evaluation and improvement loops - Implementation of AI applications using LangChain, LlamaIndex, and related frameworks
- Architecture planning from PoC to production use
- Design of integrations with existing systems and business workflows
- Requirements gathering with user departments and consultants, as well as consideration of technically feasible implementation methods
Candidate Requirements
- Practical experience in web application or business system development
- Development experience using Python, JavaScript, TypeScript, or similar languages
- Experience using generative AI tools such as ChatGPT or Claude in business or development work
- Comfortable designing systems that combine API integrations and external services
- Ability to clearly explain the background and reasoning behind technical selections and design decisions
Preferred Skills and Experience
- Experience designing and implementing RAG systems
- Experience using LangChain, LlamaIndex, or similar frameworks
- Experience using OpenAI API, Azure OpenAI, Claude API, or similar services
- Experience using vector databases such as Pinecone, Weaviate, or FAISS
- Experience developing and operating systems in cloud environments such as AWS, GCP, or Azure
- Experience implementing systems with awareness of CI/CD, logging design, and operations
How to Apply
| Salary | Negotiable based on experience and skills |
| Work Location | ・Ikebukuro Head Office, Ikebukuro, Toshima-ku, Tokyo Head Office Access: 5-minute walk from Exit C6 of Ikebukuro Station |
| Employment Type | Full-time employee |
| Work Style | Working Hours: 9:00–18:00 Working hours may vary depending on the client. Holidays and Leave: Two days off per week, annual paid leave, year-end and New Year holidays, condolence leave, and congratulatory leave for passing certifications |
| Probation Period | 1 month (No changes to employment conditions during the probation period) |
| Benefits | Full social insurance coverage, including health insurance, employees’ pension insurance, employment insurance, and workers’ compensation insurance Transportation expenses provided Certification support and allowances Casual dress code May vary depending on the project |
Business Overview
Yoimaru LLC is an IT company with a mission of “Realizing Local Creation through the Power of IT.” We support the creation of systems that enable local communities and companies to autonomously generate value.
Main Services
- PMO consulting, including planning, control, standardization, and improvement support
- ITSM / ITIL implementation and operations design support, as well as ServiceNow implementation and utilization support
- System development and implementation support
- Business improvement and DX support using AI
- In-house product and service development
Strengths
- Practical support based on an understanding of both project management and operations design
- Deep knowledge of the entire IT lifecycle, from planning and design to development and operations
- A flat organizational structure and fast decision-making made possible by a small team
- An open environment where members from diverse backgrounds can easily share their ideas