Job Description:

About Organization

The LINK Department is a diverse and technologically advanced organization within Rakuten Symphony, Inc. Our team, comprised of members from over 10 countries, values open respect and creativity. We develop "Rakuten Link," a comprehensive communication and ecosystem app for Rakuten Mobile customers. The app integrates various services, including calls, messaging, contact management, voicemail, official accounts, news, cash transfers, and point rewards, with a Desktop version that further enhances the communication experience.

We are seeking a highly skilled Senior AI/Full-Stack Engineer to join our team. This role is pivotal in driving the evolution of Rakuten Link by integrating cutting-edge AI technologies and building robust, scalable applications. You will be responsible for transforming complex product challenges into high-quality AI-driven solutions, enhancing user experience, and contributing to the next generation of our communication ecosystem.

Job Duties

• AI Agent Development: Design, develop, and maintain scalable AI agents for workflow automation. Implement agent logic, including prompt design, tool usage, and response handling, while ensuring reliability and performance.

• Full-Stack Integration: Integrate LLMs into applications using Python, JavaScript, TypeScript, or Java. Build backend services, APIs, and automation pipelines. Craft intuitive, responsive user interfaces using modern frameworks (e.g., React, Remix, Angular, Vue.js).

• Testing & Quality Assurance: Test AI outputs for accuracy, consistency, and edge cases. Debug AI workflows, resolve integration issues, and continuously improve system quality through feedback loops.

• Cross-functional Collaboration: Partner with product managers, designers, QA, and DevOps teams to gather requirements, ensure alignment, and deliver high-impact features.

• Code Excellence & Mentorship: Write clean, efficient, and reusable code. Conduct thorough code reviews and provide mentorship to junior engineers to foster a culture of continuous learning.

• Innovation & Security: Stay abreast of the latest AI/LLM trends and proactively apply them. Implement robust security measures to ensure data protection and industry compliance.

Minimum Qualifications

• Education: Bachelor’s degree in Computer Science, Engineering, AI, ML, or a related field (or equivalent work experience).

• Experience: 7+ years of progressive experience in programming (Python, Java, Kotlin, or Node.js) with a strong background in designing/maintaining REST APIs and microservices.

• Frontend Proficiency: Strong command of HTML, CSS, and modern JavaScript (ES6+). Experience with frameworks like React (Remix), Angular, or Vue.js, and state management libraries (e.g., Redux, MobX).

• AI/LLM Expertise: Proven experience designing and implementing scalable AI agents and automation platforms using LLMs. Solid understanding of ML, Deep Learning, and NLP fundamentals (TensorFlow, PyTorch, JAX, or Keras).

• Technical Foundations: Deep understanding of full-stack software development principles, design patterns, data structures, and algorithms.

• Soft Skills: Excellent analytical and problem-solving skills, with the ability to articulate complex technical concepts to both technical and non-technical stakeholders.

• Methodology: Experience working within Agile development environments.

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