▶︎Overview

*position : Software Engineer (AI Agent Product Development)

*salary : ¥6M – ¥13M

*language : Business-level Japanese required

*remote : Full remote within Japan

▶︎About the Company

A rapidly growing AI startup focused on building proprietary Japanese-language LLMs and enterprise AI solutions.

The company develops advanced generative AI technologies from scratch and provides AI-powered products for large enterprise clients across Japan.

Their AI platforms are already adopted by hundreds of major companies, and the organization continues to scale aggressively following large-scale fundraising.

Current business includes:

• AI Agent products for enterprise workflow automation
• AI implementation platforms for enterprise transformation

▶︎About the Role

You will join the early growth phase of AI Agent products and collaborate closely with PMs, designers, and engineers to build next-generation AI-driven enterprise applications.

This role requires engineers who can think beyond specifications, deeply understand customer workflows, and proactively solve both technical and product challenges.

Main responsibilities include:

• Web application prototyping and production development
• Prompt engineering and context engineering for Generative AI
• Building and improving RAG/search systems
• Data platform development
• SaaS operation monitoring and improvements
• Technical blogging and knowledge sharing

▶︎Development environment

• Languages / Frameworks: Ruby on Rails, Python, Vue.js, TypeScript, Flutter, Terraform
• Database / Middleware: Aurora MySQL, OpenSearch, DynamoDB, Redis
• Infrastructure: AWS (ECS, Lambda, Step Functions, Batch, Bedrock, Cognito, SNS, SQS, SES, etc.)
• AI / ML: OpenAI, Azure OpenAI Service, proprietary LLMs, Transformers, vLLM
• Monitoring / DevOps: Terraform, Datadog, Sentry, SendGrid

▶︎Salary

• Annual salary: ¥6,000,000 – ¥13,000,000
• Salary revision twice a year

▶︎Qualifications

Required:

• 4+ years of web application development experience
• Experience developing and operating systems on AWS/GCP/Azure
• Experience contributing to one product/service continuously for over 1 year
• Business-level Japanese communication skills

Preferred:

• Full-stack development experience
• Experience with NLP, Machine Learning, or LLM-based products
• Experience with search systems such as OpenSearch
• Experience collaborating closely with PdMs/designers
• Interest in technical blogging or community activities

▶︎Work environment

• Full remote work available anywhere in Japan
• Flexible work style with flextime system
• Engineering organization of around 20 members
• Opportunity to work on cutting-edge Generative AI products from the early phase

▶︎Allowances and Benefits

• Social insurance
• Transportation support
• Learning budget up to ¥240,000/year
• Defined contribution pension plan
• MacBook Pro provided
• Monthly research day system
• Free drinks at the office
• Regular company events and meetups
• Flexible remote-first culture

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