【Software Engineer】JLPT N2 | Flextime & Hybrid Work

★Software Engineer | AI Development Platform Provider

• Business Level Japanese Required

◆ Flextime & Hybrid Work

◆ Start-up Company

◆ Annual salary: 6 million yen - 12 million yen

-------------【About the company】-------------

Adopting a "Data-Centric AI Development" approach, the company specializes in the collection and creation of "high-quality data," which directly dictates the accuracy and safety of AI models. While it is often said that data preparation accounts for 80% of the AI development process, the company addresses this challenge through its proprietary platform.

1. In-house Product: AI Data SaaS

The company operates a platform where crowdworkers from around the world participate in annotation (creation of training data) by utilizing a mechanism similar to "poi-katsu" (reward-earning) apps. By leveraging proprietary quality-control algorithms, the company achieves low-cost and rapid data collection.

2. Data Collection and Annotation Services

The company handles a wide range of projects, from "0 to 1" new development to large-scale operational tasks based on well-defined requirements. It addresses diverse orders in cutting-edge technical fields—such as Large Language Models (LLM), Retrieval-Augmented Generation (RAG), voice recognition, and multi-modal AI—through its flexible and advanced development capabilities.

3. Provision of High-Quality Data Sets

The company provides "rights-cleared" data sets that are essential for AI training, ensuring both quality and legal compliance for its clients.

■Strengths and Track Record

The company’s client base primarily consists of enterprise-level organizations. It supports numerous top players across various industries, notably including the provision of Japanese data for Meta’s Large Language Models (LLM). Rather than being just an AI tool provider, the company has garnered significant market attention as a key player that controls "data"—the very essence of AI.

-------------【 Job Description】-------------

■About the Company

The company is a startup established to solve the "data preparation challenges" that many organizations face during AI development. It provides a cloud-based data collection and annotation platform to streamline the preparation of high-quality data essential for developing and operating AI models.

Its flagship services include an AI data platform that centrally manages data creation by both internal and external contributors, the provision of diverse training datasets, and custom solutions to support AI model development. These offerings have been widely adopted, primarily by major enterprise clients.

Furthermore, by leveraging a global network of cloud workers via a dedicated smartphone app and establishing data collection capabilities across multiple languages and regions, the company has built a robust infrastructure capable of supporting global AI initiatives.

■Recruitment Background

Centered around its AI data platform, the company is advancing large-scale product development that spans the frontend, backend, mobile, and cloud.

With client use cases covering a wide spectrum—including AI-OCR, object detection, and LLM training—there is an urgent need to develop robust and scalable systems that underpin the user experience. Against this backdrop, the company is seeking an individual who can lead full-stack development, taking responsibility for both strengthening the service foundation and developing new features.

■The Mission

As a Full-Stack Engineer, the individual will drive the end-to-end development and operation of the company’s AI data platform, ensuring a high-quality product experience that users can rely on with confidence.

Key Responsibilities

・Feature Development: Developing and improving new features for both web and mobile applications.

・Backend Architecture: Designing and implementing server-side APIs and database structures.

・Cloud Infrastructure: Designing, operating, and optimizing cloud infrastructure to ensure scalability.

・UI/UX Enhancement: Improving the user interface and experience for annotation and data collection functionalities.

・Platform Engineering: Building and maintaining DevOps/MLOps foundations and advancing CI/CD pipelines.

・Product Definition: Collaborating with the business side to define product requirements and translate them into technical implementations.

■ Technologies Used

▼ Server-Side/Backend

Languages: Python (Django), Node.js

Database: Postgres

▼ Frontend

Web

Languages: Typescript (React, Next.js)

Mobile

Languages: Typescript (React Native)

▼ Infrastructure/SRE

Cloud: AWS, GCP

Containers: Docker, Kubernetes

CI/CD: GitHub Actions

▼ Other

Data Processing/AI Integration: Google Vertex AI, AWS SageMaker, etc.

■Position Highlights

・Significant autonomy to work end-to-end across frontend, backend, and infrastructure

・Contribute to foundational development supporting cutting-edge services like AI/LLM/VLM

・Work on diverse development projects ranging from major domestic companies to international initiatives

・Challenge yourself with new technologies in a fast-paced startup environment

・Drive product growth through development directly impacting business and UX

■The Challenges Ahead

AI models are becoming increasingly sophisticated and diverse every year. Consequently, the demand for training data has shifted toward massive volume coupled with uncompromising quality. The company addresses this by providing a data collection and annotation experience that is "user-friendly, accurate, and fast" for both corporate clients and cloud workers through its mobile apps and SaaS platform.

The company's footprint is expanding beyond Japan, with ongoing collaborations in Africa, Southeast Asia, and Europe. Looking ahead, the company will focus on specialized annotation and the creation of instruction data for next-generation AI, including RAG, LLM, and VLM.

-------------【 Requirements】-------------

Required

・Practical experience in web application development

・Development experience using languages such as Python, Node.js, and TypeScript

・Design and operational experience using RDBMS (e.g., Postgres)

・Development and operational experience in cloud environments (e.g., AWS, GCP)

Preferred

・Experience developing services utilizing large-scale models such as LLM/VLM

・Experience with modern frontend development using React / Next.js / React Native

・Experience developing in containerized environments using Docker / Kubernetes

・Experience developing systems involving multilingual support and image/video data processing

・Experience building and operating data pipelines and MLOps infrastructure

Ideal Applicants

・Strong interest in product development supporting AI and data utilization

・Proactive attitude toward learning and adopting new technologies and methodologies

・Values team collaboration and communicates flexibly

・Wants to contribute to product growth by engaging broadly across frontend, backend, and cloud infrastructure

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◾️Holidays & Leave

・Annual Paid Leave

・Saturdays, Sundays, and National Holidays

・Summer Vacation

・Year-End and New Year Holidays

・Special Leave for Family Events

・Maternity Leave

・Childcare Leave

・Menstrual Leave

◾️Employee Benefits

・Full Social Insurance Coverage

・Full transportation expense reimbursement

・Health checkups

・Influenza vaccinations

・Book purchase expense coverage

・Conference participation fee coverage

・In-house study sessions

・Company meal expense support

・1-on-1 meetings

・Free drinks

・Monitor loan

・Vending machines available

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