Careers
Who is YEJIN looking for?
YEJIN is a team solving the problem of 'connection' at the forefront of AI technology. We want to work with people who look for better questions rather than finished answers.
Culture
How We Work
We prove it with technology
We speak through evidence and results, not job titles.
We experiment quickly
We prefer small experiments and fast learning over perfect plans.
We grow together
Code reviews, knowledge sharing, and retrospectives are the basics of how we work.
Positions
Open Positions
We are currently hiring for 9 positions. Select a position to see its responsibilities and requirements.
Development DivisionFrontend Developer
Build the ZeliAi web service with React and Next.js and elevate the user experience.
Frontend Developer
Build the ZeliAi web service with React and Next.js and elevate the user experience.
Responsibilities
- Develop and maintain React-based web applications
- Optimize user experience (UX) and interface (UI)
- Integrate backend APIs and handle data
- Improve code quality and performance and develop new features
- Collaborate with the design and planning teams and build components with Tailwind CSS
Requirements
- Experience developing with React, Next.js, and TypeScript
- Deep understanding of HTML, CSS, and JavaScript
- Experience with state management libraries (Redux, Recoil, etc.)
- Experience integrating RESTful APIs and GraphQL
- Experience integrating backend frameworks such as Django and FastAPI
- Experience with Git- and Docker-based development
- Experience with performance optimization and cross-browser support
Preferred Qualifications
- Experience developing AI service or chatbot UIs
- Experience developing multimodal (voice, image, text) UX/UI
- Experience with data visualization and interactive UI using WebGL and Three.js
- Experience building Storybook and design systems
- Experience building CI/CD-based automated frontend deployment environments
- Experience with i18n (multilingual support) for global services
Development DivisionBackend Developer (AI API Integration)
Design and operate ZeliAi's APIs and service infrastructure with Django and FastAPI.
Backend Developer (AI API Integration)
Design and operate ZeliAi's APIs and service infrastructure with Django and FastAPI.
Responsibilities
- Develop and maintain the backend using Django and FastAPI
- Design and implement RESTful APIs
- Design and optimize databases (PostgreSQL, MySQL, etc.)
- Operate services on AWS cloud and in Docker and Kubernetes environments
- Build and operate CI/CD pipelines
- Develop authentication and security systems (JWT, OAuth, etc.)
Requirements
- Deep understanding of and development experience with Python, Django, and FastAPI
- Experience designing and implementing RESTful APIs
- Experience with database modeling and optimization (PostgreSQL, MySQL, etc.)
- Experience developing in container environments such as Docker
- Experience using Git-based version control systems
- Experience with asynchronous programming and performance optimization
Preferred Qualifications
- Experience handling large-scale traffic
- Experience using message queues such as Redis, RabbitMQ, and Kafka
- Experience operating services in AWS, GCP, and Azure cloud environments
- Experience writing test code and practicing TDD
- Understanding of web security and data protection
- Experience contributing to open source or running a technical blog
- Candidates eligible for government employment incentives (Employment Promotion Subsidy · Youth Job Leap Incentive)
ZeliAiAI Agent Developer (Agent Orchestration Engineer)
Build domain-specific AI agents with LLM orchestration and multimodal search.
AI Agent Developer (Agent Orchestration Engineer)
Build domain-specific AI agents with LLM orchestration and multimodal search.
Responsibilities
- Compose domain-specific AI agents within the ZeliAi platform and plan new services
- Design and implement a multimodal question-and-answer orchestration system
- Develop an integrated LLM response system using LangChain, the OpenAI API, and more
- Advance automatic report generation based on user requests and enhance multimodal search
Requirements
- Python, FastAPI, LangChain (Node.js optional)
- Experience integrating major LLMs such as the OpenAI API, Claude, Bard, and Grok
- Experience using vector databases based on FAISS or Weaviate
- Experience with text, image, and voice processing (GPT-4o, Whisper, Stable Diffusion, etc.)
- Architecture design based on LangGraph, ReAct, Toolformer, and Function Calling
- Experience using AWS, GCP, Docker, Git, and MLOps tools
- Experience with natural language processing and AI orchestration, and the ability to interpret English documents
Preferred Qualifications
- Experience with natural language processing-based services
- Comfortable in a startup environment
- Ability to design agent UX and scenarios
- Experience automating AI-based PDF reports
ZeliAiAndroid and iOS Developer
Develop hybrid apps that integrate STT/TTS and on-device sLM in real time.
Android and iOS Developer
Develop hybrid apps that integrate STT/TTS and on-device sLM in real time.
Responsibilities
- Real-time integration of STT/TTS and sLM
- Automatic customer recognition and personalized screens based on BLE and Wi-Fi
- Two-way real-time integration with unmanned kiosks
- Enhance hybrid apps combining WebView and Native
- Deploy and operate on the App Store and Play Store
Requirements
- 3+ years of experience with commercial mobile app services
- At least one hands-on integration of STT or TTS
- At least one experience with BLE- or Wi-Fi-based proximity or location recognition
- Experience with REST API + WebView hybrid apps
- Proficiency in Kotlin or Swift
- Experience deploying to the Play Store and App Store
Preferred Qualifications
- Experience integrating with kiosk, POS, and IoT devices
- Experience serving on-device sLM or LLM (Whisper, Piper, Core ML, etc.)
- Hands-on experience with Jetpack Compose or SwiftUI
- Experience integrating the OpenAI, Claude, Gemini, and Grok APIs
- Experience quickly launching MVPs at a startup
AI ResearchData Scientist
Internalize lightweight, high-speed inference through sLM fine-tuning and multi-model orchestration.
Data Scientist
Internalize lightweight, high-speed inference through sLM fine-tuning and multi-model orchestration.
Responsibilities
- sLM optimization and fine-tuning — exploring and fine-tuning lightweight language models specialized for service goals (LoRA, QLoRA, QDoRA, etc.)
- Designing multi-sLM orchestration — designing multi-agent pipelines that overcome the limits of a single model and building routing and coordination logic across models
- Internalizing model compression and high-speed inference — applying quantization (AWQ, GGUF) techniques and building a serving architecture using inference engines
- E2E integration support — ensuring generative AI models and prompt pipelines integrate smoothly with backend services (APIs) and enhancing quality
Requirements
- 3+ years of experience in data analysis, machine learning, AI research, or backend and data engineering
- Overall understanding of natural language processing (NLP) and transformer-based generative AI (LLM/sLM) architectures
- Experience using the Hugging Face ecosystem (downloading, training, inference)
- Experience using AI orchestration frameworks such as LangChain, LlamaIndex, and AutoGen
- High proficiency in Python and the ability to use PyTorch-based deep learning frameworks
Preferred Qualifications
- Full-stack development capability — able to build prototypes across the backend (FastAPI, Ktor, etc.) and frontend (React, Next.js)
- Experience setting up everything from model download to system load directly in on-premises and local environments without relying on a specific cloud API
- Experience building RAG (retrieval-augmented generation) systems and operating vector databases
- Comfortable with Git- and Docker-based collaboration and deployment environments
DesignUI/UX Web Designer
Design YEJIN's interfaces, from the homepage to web and mobile services.
UI/UX Web Designer
Design YEJIN's interfaces, from the homepage to web and mobile services.
Responsibilities
- Design the homepage and various web pages
- Design interfaces for web and mobile applications
- UI/UX design and improvement — increasing satisfaction through interface design that considers the user experience
- Analyze design trends and apply them to projects
- Write and manage documentation such as design guidelines and style guides
Requirements
- 1+ years of web design experience (able to demonstrate hands-on project management and design capability)
- Excellent design quality and a creative design sense (proven through a portfolio)
- Deep understanding of UI/UX design and experience improving it
- Portfolio submission required
Preferred Qualifications
- Experience designing across various platforms including web, mobile, and desktop
- Design major or completion of a publishing course at a professional training institution
- Candidates eligible for the Employment Promotion Subsidy
- Candidates eligible for the Youth Job Leap Incentive
Corporate Strategy OfficeBusiness Planning · Government Projects · Investment / Patents · Legal · Certifications · Strategic Partnerships
Design the foundation for the company's growth, from business plans and IR to intellectual property and strategic partnerships.
Business Planning · Government Projects · Investment / Patents · Legal · Certifications · Strategic Partnerships
Design the foundation for the company's growth, from business plans and IR to intellectual property and strategic partnerships.
Responsibilities
- Mid- to long-term business planning across the company and ZeliAi
- Writing and managing business plans related to government support programs, R&D projects, policy funds, technology assessments, and guarantees/loans
- Handling external programs such as TIPS, the Super-Gap Startup program, and the Early-Stage Startup Package
- Writing IR materials and investment proposals for VCs, ACs, angels, and strategic investors
- Managing and supporting the filing of intellectual property such as patents, trademarks, and copyrights
- Reviewing and managing legal documents such as contracts, NDAs, MOUs, and license agreements
- Handling various quality, security, and technology certifications such as venture company and corporate research institute status
- Identifying strategic partnerships with domestic and international partners and institutions and designing collaboration structures
Requirements
- Hands-on experience in business planning, strategic planning, government projects, and investment
- Strong ability to write business plans, proposals, IR decks, funding applications, and technical descriptions
- Excellent ability to write logical documents and structure presentation materials
- Basic understanding of financial structure, market analysis, and business model design
- Basic hands-on capability in reviewing contracts and legal documents
- Experience communicating with external institutions and stakeholders
Corporate Strategy OfficeService Planning · Marketing · Public Relations
Jointly lead ZeliAi's service planning and the growth of brand awareness.
Service Planning · Marketing · Public Relations
Jointly lead ZeliAi's service planning and the growth of brand awareness.
Responsibilities
- Establish service planning and operational strategy for the ZeliAi platform
- Plan service policies, feature structures, and screen-flow UX from the user's perspective
- Plan enhancements to related services such as AI search, AI agents, Multi-Brain, and the Aggregator
- Plan landing pages, events, promotions, content marketing, and partnership marketing
- Establish SNS channel operation strategy and plan PR and marketing content
- Promote the brand and expand traffic through SNS such as Instagram, YouTube, TikTok, blogs, and Threads
- Data-driven user analysis and improvement of feature activation and paid-conversion funnels
- Plan press releases, handle media coverage, and write PR content
Requirements
- Hands-on experience in service planning, platform planning, digital marketing, brand planning, or content planning
- Understanding of the planning, operation, and improvement processes of web and app services
- User-centered thinking and data-driven problem-solving capability
- Excellent documentation and communication skills
- Ability to logically organize brand, service, and market messaging
- High interest in and understanding of AI, SaaS, and platform businesses
Preferred Qualifications
- Experience planning AI services, SaaS, search services, and platform services
- Experience in a PM/PO role
- Experience running performance marketing, CRM, and retention strategy
- Experience using collaboration and analytics tools such as Notion, Figma, Jira, GA4, and Mixpanel
- Experience working at an early-stage startup or high-growth organization
- Experience in content planning, branding, and campaign operation
- Experience writing press releases, communicating with the media, and handling PR
Corporate Management OfficeFinance and Accounting (Experienced)
Own financial administration end to end, from closing and taxes to government-subsidy settlements.
Finance and Accounting (Experienced)
Own financial administration end to end, from closing and taxes to government-subsidy settlements.
Responsibilities
- Maintaining accounting books and closing
- Tax filing (VAT, withholding tax) and handling external audits
- Fund management and financial planning
- Accounting settlement of government subsidies and R&D
- Operating and improving the accounting management system
- Overall financial administration including corporate tax, local tax, and expense management
Requirements
- Bachelor's degree or higher (related major such as accounting, business, or economics)
- 3+ years of hands-on corporate finance, accounting, and tax experience
- Experience with corporate closing and handling audits
- Experience with tax filing and tax risk management
- Ability to use ERP (Douzone, SAP, etc.)
- Understanding of corporate accounting standards (K-GAAP, K-IFRS)
- Strong proficiency with MS Office such as Excel and PowerPoint
Preferred Qualifications
- Experience in finance and accounting at a venture or startup
- Experience settling government support programs
- Holder of accounting or tax certifications (Computerized Tax Accounting, FAT, AICPA, etc.)
- Excellent communication and collaboration skills
Conditions
Working Conditions
Employment Type
Full-time (3-month internship for experienced hires)
Location
Seoul headquarters (Samjeon-dong, Songpa-gu) corporate research institute
Working Hours
09:00 - 18:00
Compensation
Per internal policy — we operate an advanced HR evaluation system and, following our contribution-first compensation rules, provide salary-increase opportunities through HR evaluations held four times a year.
Benefits
Benefits & Culture
Compensation and Equity
The four major insurances and statutory benefits, salary and promotion rewards based on performance evaluations, long-term stock options for key talent, and top-priority employee stock ownership for outstanding employees.
Growth Support
Support for AI, technology, and business education and skill development, coverage of costs for attending conferences and seminars and taking online courses, and opportunities to participate directly in core ZeliAi projects.
Awards and Workshops
Long-service awards, outstanding-employee awards, project performance bonuses, one overseas workshop per year, and one domestic workshop per year.
Family and Life
Children's tuition support, congratulatory bonuses for birthdays, marriage, childbirth, and children's school entrance (regardless of the number of children), a paid half-day early leave on your birthday, and regular health checkups.
Work Environment
A newly built office with the latest facilities, a cafeteria with cooking facilities and snacks provided, and an autonomous work atmosphere where creativity can flourish.
Process
Hiring Process
We review applications in the order received and notify you individually of the results at each stage.
- 1
Application Review
We notify candidates individually of interview schedules, for successful applicants only.
- 2
Coding Test
Conducted as needed, for development roles only.
- 3
Technical and Practical Interview
We assess both job capability and how you collaborate.
- 4
Final Offer
We coordinate the start date after discussing terms.
Application Documents
- Resume and cover letter
- Career description (project-focused) and certificate of employment
- Portfolio (required for design and development roles)
Please submit your application through the recruiting inquiry below. Documents you submit are used only for the hiring process and no other purpose.
Frequently Asked Questions
Please apply through 'Recruiting Inquiry' at the bottom of the careers page, indicating the position you'd like to apply for and attaching your application documents such as your resume and portfolio.
You can review the responsibilities and requirements under the open positions on the careers page. If you're interested in a role that isn't posted, please leave us an inquiry.
Please prepare a resume and cover letter, a career description (for experienced applicants), and a portfolio (required for design and development roles).
The process proceeds as application review → coding test (development roles only, as needed) → technical and practical interview → final offer, and we provide individual updates on the results at each stage.
We notify the next stage's schedule individually, for successful applicants only. The documents you submit are used solely for hiring purposes and are managed securely in accordance with relevant laws.
Want to grow with YEJIN?
Leave an inquiry with the position you're interested in, and we'll review it and get back to you.