Backend Engineer (Tech Lead)

Role and responsibilities
This position is part of the Media Business Unit’s Development Section and Backend Team, working on the Kurashiru recipe product. The immediate focus is to develop features for the Kurashiru app and web services, resolve backend technology issues, promote the use of AI in engineering, and create new core experiences such as AI-powered features. Over the longer term, the role contributes to development across media and other businesses, technical strategy design, and discussions with management. It may also involve full-stack development with frontend and infrastructure as secondary areas, as well as management of the backend organization.

Technical environment
The backend uses Ruby 3.4 and Rails 8.1, with MySQL as middleware. Infrastructure configuration is managed with Terraform. Monitoring includes Amazon CloudWatch, Datadog, and Sentry. The AWS environment includes ECS, RDS, ElastiCache, DynamoDB, SQS, S3, and Lambda. Frontend technologies include React, TypeScript, Jotai, react-dom/server, and Node.js. The data and analytics environment includes Snowflake, dbt, Lightdash, Athena, and Google Analytics. CI/CD uses GitHub Actions, CodePipeline, and CodeBuild. AI-related tools and services named in the posting include Claude Code, Codex, Cursor, Amazon Bedrock, Devin, Gemini, and NotebookLM.

Product and team context
Kurashiru has accumulated 44 million iOS and Android downloads and is used by 56 million people each month. The development organization works with a small team on a large-scale product and aims to increase the value each engineer can create by expanding into adjacent areas such as product management, design, frontend, and backend. The position is expected to lead from the backend domain while working with business and development members in a mixed Biz/Dev Scrum process. Business-side and engineering-side members communicate in both directions during Scrum events and development work, using a PDCA cycle.

The organization also addresses technical debt alongside feature development and promotes AI use across both engineering and product work. Product development uses behavioral data generated during cooking and Kurashiru’s recipe data and user feedback. Examples of stated initiatives include structuring user-generated recipes, ingredients, and procedures, and using AI to suggest substitute ingredients and summarize user reviews and questions from multiple perspectives.

The stated work location is in Shibaura, Minato-ku, Tokyo, at msb Tamachi Station Tower N.