WHO WE ARE:

• We are looking for an AI Fullstack Engineer who specializes in integrating LLMs into production systems
• You will work on product engineering, leveraging existing AI platforms (OpenAI, Azure OpenAI, Microsoft AI services…) to deliver scalable, production-ready solutions.

WHAT WE DO

At Sun Asterisk, we build cutting-edge AI solutions that leverage the power of LLMs and modern AI platforms to drive innovation, transform industries, and empower businesses worldwide.
As an AI Fullstack Engineer, you will:

• Design, develop and maintain frontend and backend features using TypeScript, React, Next.js or equivalent frameworks
• Build and maintain backend services and APIs (tRPC, REST, GraphQL or similar)
• Integrate LLM-based features using OpenAI / Azure OpenAI / MS AI APIs
• Apply Prompt Engineering techniques to optimize response quality, consistency, and cost
• Design and implement RAG systems by connecting internal data sources to LLMs
• Work with vector databases and embeddings to support semantic search and AI-powered workflows
• Collaborate closely with Design, AI stakeholders to deliver end-to-end features
• Optimize database schemas and queries using PostgreSQL and modern ORM/query builders
• Ensure code quality through code reviews, testing, logging, and monitoring
• Continuously learn and experiment with new AI capabilities and apply them to product improvements

WHO YOU ARE

#Experience Requirements
Mandatory Skills:

• 3+ years of experience as a Fullstack, Backend, or Frontend Engineer
• Strong proficiency in TypeScript or experience with Node.js / Python / Golang
• Experience building production applications with React and/or Next.js
• Solid experience designing and consuming backend APIs (REST, GraphQL, tRPC, etc.)
• Hands-on experience integrating LLMs into applications (OpenAI, Azure OpenAI, or similar)
• Good understanding of:
  • How LLMs work at a conceptual level
  • Prompt Engineering in real use cases
• Practical experience with RAG or similar LLM-data integration patterns
• Familiarity with vector databases / embeddings
• Experience working with PostgreSQL and performance optimization
• Collaborative mindset, product thinking, and strong ownership.

Desired Skills:

• Experience with AI agents or multi-step AI workflows..
• Familiarity with Tailwind CSS, Zod, Vercel, serverless or edge architectures
• Experience building AI-powered SaaS or internal platforms
• Awareness of cost, latency, and reliability considerations in AI integration.

#Skill requirements

• Excellent English communication skills
• Outstanding teamwork abilities
• Proven ability to prioritize and allocate work
• Sharp critical thinking and logical reasoning
• Effective problem-solving skills

#Attitude Requirements

• Customer-centric mindset
• Adaptability to change
• Commitment to continuous learning and growth

BENEFITS AND PERKS

Professional, open-minded, and creative environment:

• Work with colleagues who embrace ideas to change the society
• Respect different perspectives within a team
• Strong learning culture that promotes individual development
• The culture of taking risks to experience and thrive

Focus on individual development:

• Be consulted, accompanied, and supported in career development with the career path system (developing in expertise or management direction) that has been studied and tested for many years.
• Be oriented for individual, group, and organizational goals
• Be empowered
• Be supported to define a 3-month or 6-month goal (Goal Define Support)
• Get access to company Learning Hub online library with various courses provided by Udemy, LinkedIn,…

Special care for employees:

• Salary: Negotiable + competitive allowance (lunch, living allowance, beauty care, Japanese and IT certificates, etc.)
• 13th-month salary bonus
• Performance review: Twice/a year
• Hybrid working policy; flexible check-in, check-out
• Comprehensive health insurance Sun* Care
• Seniority Allowance
• Women care allowance: Women’s physiological leave: 2.5 hours/month; Postpartum leave for female employees with under 1-year-old children: 1 hour/day
• Policies supporting learning activities, knowledge sharing, and cultural exchange (Technology Seminar – Tech Expert, Club: Reading, Japanese, Music Club, …)
• Annual company trip and quarterly team-building activities

Note: By applying for this position, you consent to Sun* collecting, storing, and processing your personal data for current and future recruitment purposes. Your data may be shared with relevant parties involved in the recruitment process and will be retained indefinitely until you submit an official written request for its deletion.