Java Developer

Core AI Backend Engineer – LLM Fine-Tuning

You know that moment when you don’t just debug code — you train a model, fine-tune it, and suddenly it understands your domain better than you expected? That’s the kind of magic we’re looking for.

We’re building something that turns chaotic social video data into crystal-clear business intelligence. Not just another API — but AI-backed architecture fine-tuned to our world. Systems that marketing teams thank you for, because they feel the intelligence, not just the infrastructure.

Either you feel the craft when you read this, or you don’t. This isn’t just another backend role. This is where you bring together scalable systems and cutting-edge LLMs to build something the world hasn’t seen before.

Who We Are

We’re a small, global team that ships fast. Every line of code and every model choice affects millions of video analysis requests.

Our engineers don’t just build APIs — they architect solutions, they optimize at scale, and now, they fine-tune models to make AI work in the real world. Our CPTO still codes. Our senior engineers make complexity look effortless. Our backend team sets a standard that others ask how we move so fast.

What We Need

We need someone who’s lived both sides of this life:

• Backend excellence: building high-scale, high-performance systems.
• LLM fine-tuning: hands-on with open-source models, not just calling APIs.

Someone who can sit with a requirement at 2pm and by 6pm not only has endpoints working, but also has a fine-tuned model running behind them — customized to our use case.

Your Craft

• JavaScript/TypeScript & NodeJS as core backend tools.
• Next.js for full-stack where needed.
• Rust when performance is non-negotiable.
• Golang/Python as comfortable tools of choice.
• MySQL/Postgres/Redis — wielded with intention.
• AWS ecosystem — your playground, not your puzzle.
• LLM/AI integration you’ve actually shipped.
• Open-source LLM fine-tuning experience:
• Bringing in open-source models (LLaMA, Mistral, Falcon, etc.).
• Fine-tuning/adapting them for specific domains.
• Optimizing for inference cost, latency, and accuracy.

The Reality

The work is beautifully complex. The scale is real and growing. The problems are the kind that wake you up at 3am with solutions.

If you get your energy from building backend systems and adapting LLMs to make them smarter for real-world use, you’ll probably fall in love with what we do. If you’re only interested in APIs without touching models, this won’t be your thing — and that’s completely okay.

How to Apply

If you’re reading this thinking “finally, a team that actually cares about real AI engineering” — we’d love to see something you’ve built.

Not just a resume. Show us your craft:

• An LLM fine-tuning repo.
• A domain-adapted model you worked on.
• A system design where you combined backend and AI.
• Or even a short write-up or voice note explaining what you’ve fine-tuned.

We’re genuinely excited to see what you’ve done and have a meaningful conversation about whether this could be magic for both of us.

Job Description:

We are seeking a highly motivated and skilled Full Stack Java Developer with strong experience in backend and frontend development, cloud deployment, and modern DevOps practices. The ideal candidate will have a solid background in Java/J2EE technologies, hands-on experience in developing microservices on AWS, and a good understanding of CI/CD pipelines and monitoring tools.

Key Responsibilities:

• Design, develop, test, and maintain scalable web applications and microservices.
• Implement backend logic using Core Java, J2EE, Spring Boot, Spring Batch, JPA, and REST APIs.
• Build responsive UIs using React, HTML, CSS, and integrate them with backend services.
• Develop and deploy microservices using AWS services like ECS, EC2, S3, API Gateway, Aurora, ALB, and Route 53.
• Participate in Agile development processes, including sprint planning, stand-ups, and retrospectives.
• Write unit and integration tests using JUnit and Cucumber.
• Monitor application performance using APM tools and analyze logs using Splunk or similar tools.
• Implement CI/CD pipelines using Jenkins, Maven/Gradle, and Git/Bitbucket.
• Work with containerization and orchestration tools like Docker and Kubernetes.
• Collaborate with cross-functional teams using tools like JIRA and Confluence.

Required Skills & Experience:

• Strong hands-on experience in Java/J2EE application development.
• Proficiency in Spring frameworks (Spring Boot, Batch) and RESTful services.
• Frontend development experience with React, HTML, CSS.
• Solid experience with AWS cloud technologies and deployment practices.
• Experience in writing and maintaining automated tests with JUnit and Cucumber.
• Knowledge of APM tools and log analysis tools (e.g., Splunk).
• Familiarity with CI/CD pipelines and tools (Jenkins, Maven/Gradle, Git).
• Experience with Docker and Kubernetes.
• Excellent problem-solving, debugging, and analytical skills.
• Good communication skills and ability to work in Agile teams.

Preferred Qualifications:

• AWS certification is a plus.
• Experience with Amazon Aurora and API Gateway in production environments.
• Knowledge of SOA, messaging systems (e.g., MQ), and security best practices.

As a PHP Backend Developer, your primary responsibility will be to develop and maintain the server-side logic of web applications, ensuring high performance, responsiveness, and scalability. You will work closely with the front-end development team, project managers, and other stakeholders to deliver robust and efficient web solutions.

Responsibilities:

• Develop and maintain server-side applications using PHP frameworks (such as Yii, Laravel, Symfony, and CodeIgniter) and other related technologies.
• Write clean, well-structured, and reusable code following industry best practices and coding standards.
• Collaborate with front-end developers to integrate user-facing elements with server-side logic.
• Design and implement secure and efficient APIs for data exchange with the front end and external services.
• Optimize application performance by identifying and resolving bottlenecks, improving code efficiency, and implementing caching mechanisms.
• Ensure data integrity and implement proper validation and error-handling techniques.
• Collaborate with database administrators to design and optimize database schemas and queries.
• Conduct thorough testing and debugging of applications to ensure high-quality deliverables.
• Stay updated with the latest trends and advancements in PHP development and related technologies.
• Participate in code reviews and provide constructive feedback to maintain code quality and improve team collaboration.
• Collaborate with the project management team to estimate project timelines and deliver work within specified deadlines.
• Troubleshoot and resolve production issues, provide technical support and perform maintenance tasks as required.

Requirements:

• Proven work experience as a PHP Backend Developer or similar role.
• Strong proficiency in PHP and its frameworks (Yii, Laravel, Symfony, etc.) with a good understanding of object-oriented programming principles.
• Experience with frontend technologies (HTML5, CSS3, JavaScript) and their integration with backend systems.
• Familiarity with database systems, such as MySQL, PostgreSQL, or MongoDB, and proficiency in writing efficient database queries.
• Knowledge of version control systems like Git for code collaboration and deployment.
• Familiarity with RESTful API development and integration of third-party APIs.
• Experience in optimizing application performance and implementing caching techniques.
• Understanding of security principles and best practices for web application development.
• Excellent problem-solving and analytical skills with strong attention to detail.
• Good communication and teamwork skills to collaborate effectively with cross-functional teams.
• Ability to work independently and handle multiple projects simultaneously.

Not just a delivery company…

RaRa Delivery is revolutionising instant delivery for e-commerce in Indonesia through data driven logistics.

RaRa Delivery is making instant and same-day deliveries scalable and cost-effective by leveraging a differentiated operating model and real-time optimisation technology. RaRa makes it possible for anyone, anywhere to get same day delivery in Indonesia. While others are focusing on ‘one-to-one’ deliveries, the company has developed proprietary, real-time batching tech to do ‘many-to-many’ deliveries within a few hours.. RaRa is already in partnership with some of the top eCommerce players in Indonesia like Blibli, Sayurbox, Kopi Kenangan and many more.

We are a distributed team with the company headquartered in Singapore 🇸🇬 , core operations in Indonesia 🇮🇩 and technology team based out of India 🇮🇳

Future of eCommerce Logistics.

• Data driven logistics company that is bringing in same day delivery revolution in Indonesia 🇮🇩
• Revolutionising delivery as an experience
• Empowering D2C Sellers with logistics as the core technology

• 5 - 7 years Experience with the following technologies: Core Java/J2EE, Spring Boot, Creating API, Hibernate, JDBC, SQL/PLSQL, messaging architecture, REST/Web services, Linux
• Expertise in application, data and infrastructure architecture disciplines
• Advanced knowledge of architecture, design and business processes
• 4+ years of Java, J2EE development experience
• Strong technical development experience in effectively writing code, performing code reviews, and implementing best practices on configuration management and code refactoring
• Experience in working with vendor applications
• Experience in making optimized queries to MySQL database
• Proven problem solving and analytical skills
• A delivery-focused approach to work and the ability to work without direction
• Experience in Agile development techniques, including Scrum
• Experience implementing and/or using Git
• Ability to work collaboratively in teams and develop meaningful relationships to achieve common goals
• Bachelor degree in Computer Science or related discipline preferred

We are looking for a Node.js Developer responsible for managing the interchange of data between the server and the users. Your primary focus will be the development of all server-side logic, definition and maintenance of the central database, and ensuring high performance and responsiveness to requests from the front-end. You will also be responsible for integrating the front-end elements built by your co-workers into the application. Therefore, a basic understanding of front-end technologies is necessary as well.

• Integration of user-facing elements developed by front-end developers with server side logic
• Writing reusable, testable, and efficient code
• Design and implementation of low-latency, high-availability, and performant applications
• Implementation of security and data protection
• Integration of data storage solutions 

• Strong proficiency with JavaScript 
• Knowledge of Node.js and frameworks available for it 
• Understanding the nature of asynchronous programming and its quirks and workarounds
• Good understanding of server-side templating languages 
• Good understanding of server-side CSS preprocessors 
• Basic understanding of front-end technologies, such as HTML5, and CSS3
• Understanding accessibility and security compliance
• User authentication and authorization between multiple systems, servers, and environments
• Integration of multiple data sources and databases into one system
• Understanding fundamental design principles behind a scalable application
• Understanding differences between multiple delivery platforms, such as mobile vs. desktop, and optimizing output to match the specific platform
• Creating database schemas that represent and support business processes
• Implementing automated testing platforms and unit testses 
• Proficient understanding of code versioning tools, such as Git
• candiates who built apps, workedd with companies, participated &won in hackathons only prefered