Backend Engineer | (SD1/SD2)

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 Title: Senior Node.js Developer

Company: Transact Bridge

Location: Noida, Uttar Pradesh

Experience: 4–7 Years

Industry: FinTech / Payments / Cross-Border Commerce (LinkedIn)

About the Company:

Transact Bridge is a fast-growing fintech company enabling global businesses to expand into India through its Merchant of Record (MoR) infrastructure. The company specialises in payment processing, compliance management, subscription billing, taxation, and cross-border payment solutions for global SaaS, digital product, and e-commerce businesses. (LinkedIn).

Role Overview:

We are looking for a highly skilled Senior Node.js Developer to join our engineering team. The ideal candidate will have strong experience building scalable backend systems, APIs, and microservices in high-growth product environments. Experience in fintech, payment gateways, subscription platforms, or transaction-heavy applications will be a strong advantage.

Key Responsibilities:

• Design, develop, and maintain scalable backend applications using Node.js and TypeScript.
• Build and optimize RESTful APIs and microservices architecture.
• Integrate payment gateways, third-party APIs, and external services.
• Develop secure, high-performance, and fault-tolerant systems.
• Collaborate with product, frontend, and DevOps teams to deliver new features.
• Optimize database performance and ensure data integrity.
• Write clean, reusable, and maintainable code following best practices.
• Participate in code reviews, architecture discussions, and technical planning.
• Troubleshoot production issues and implement long-term solutions.
• Ensure application security, scalability, and compliance standards.

Required Skills:

• 4–7 years of experience in backend development.
• Strong expertise in Node.js, Express.js, and TypeScript.
• Experience building REST APIs and microservices.
• Strong understanding of asynchronous programming and event-driven architecture.
• Hands-on experience with MongoDB or similar databases.
• Experience with Redis, caching strategies, and queue management systems.
• Familiarity with AWS, Lambda, Docker, and cloud-native applications.
• Knowledge of Git, Github workflow pipelines, and software development best practices.
• Strong problem-solving and debugging skills.

Good to Have:

• Experience in FinTech, Payments, Banking, SaaS, or Subscription-based products.
• Exposure to payment gateways, UPI, recurring payments, and transaction processing.
• Experience with GraphQL, Kafka, RabbitMQ, or similar technologies.
• Knowledge of system design and distributed architectures. (Get Me Referred)

What We Offer:

• Opportunity to work on a global fintech product.
• Exposure to cross-border payment infrastructure and high-scale systems.
• Fast-paced startup environment with ownership and growth opportunities.
• Collaborative engineering culture and direct impact on product development.
• Competitive compensation and performance-driven growth.

About the Role

Unico Connect is an AI-first technology partner that builds custom mobile, web, and AI products for clients across multiple geographies. We are hiring a Backend Engineer for a dedicated client engagement building an AI-powered application builder platform.

The backend is the operational core of the product: it manages user projects and sessions, coordinates long-running AI agent workloads, maintains project state, and serves as the integration layer between the frontend, the AI system, and the underlying infrastructure.

The mandatory requirement is hands-on production experience shipping Node.js services, with end-to-end ownership of API design, data modelling, and at least one production system involving background job processing or event-driven patterns.

Responsibilities

API and service development: Design and build REST APIs in Node.js with TypeScript. Cover authentication, session management, input validation, structured error handling, streaming responses (SSE, WebSockets), and rate limiting. Maintain clean API contracts that the frontend and AI system can rely on.

Database design and management: Own PostgreSQL schema design for product domains including user accounts, projects, file trees, session state, and generated artefacts. Write efficient queries, manage migrations, and optimise for read patterns that serve a real-time editor experience.

Caching strategy: Implement and maintain caching with Redis for session data, project state, and frequently read configuration. Design cache invalidation logic that keeps the editor experience consistent without stale reads.

Queue and background job management: Implement and operate background job infrastructure using BullMQ or equivalent. AI agent runs are long-running and stateful; handle retries, failure states, priority queues, and concurrency limits.

AI system integration: Build the integration layer between the backend and the AI agent system. Manage job dispatch, result handling, streaming output to the frontend, and error propagation.

Multi-tenancy and access control: Implement tenant data isolation, RBAC, and resource ownership enforcement across all API surfaces.

Observability and reliability: Instrument services with structured logging, metrics, and tracing. Write defensive code with sensible timeouts, fallback behaviour, and circuit breaking on external dependencies.

Testing and code quality: Write unit and integration tests for the services you ship. Review the work of peers and contribute to shared engineering conventions.

Requirements

• Hands-on production Node.js experience (mandatory) — must have personally shipped at least one feature area end to end in a production Node.js service, owning API design, data modelling, and testing.

• 3 to 5 years of professional backend engineering experience. Candidates with slightly less time but strong demonstrated ownership are welcome to apply.

• Strong Node.js and TypeScript. Production experience with Express, NestJS, or Fastify. Solid with async patterns, streaming, error handling, and building services that run reliably under sustained load.

• PostgreSQL depth. Schema design, query writing, indexing, and migrations on at least one production system.

• Redis and caching. Production experience using Redis for caching and session management. Understands cache invalidation trade-offs.

• Queue and background job systems. Hands-on with BullMQ, RabbitMQ, SQS, or equivalent. Experience managing retries, dead-letter queues, job priority, and concurrency control.

• AWS working knowledge. Comfortable with EC2, S3, RDS, SQS, and IAM. Familiar with Docker and basic deployment and environment management.

• Strong written and spoken English. Able to communicate clearly with engineers across disciplines and write precise technical documentation.

Nice to Have

Experience integrating with AI or LLM services (streaming responses, structured outputs, retry patterns); WebSocket or SSE implementation for real-time features; multi-tenant SaaS product experience; GraphQL; OpenTelemetry instrumentation; prior work on developer tools or editor-style products.

Job Title: Senior Backend Developer – Ecommerce Marketplace

Company: Bharat Agrolink

Location: Bhopal, Madhya Pradesh (On-site)

Job Type: Full-time

Experience Required: 3+ Years

About Bharat Agrolink

Bharat Agrolink is a fast-growing agri-tech ecommerce marketplace focused on connecting farmers, vendors, and distributors across India. Our platform is built to simplify agricultural commerce and bring quality agri-products closer to farmers through technology-driven solutions.

We are looking for a Senior Backend Developer who can take ownership of backend architecture, scalability, and performance of our ecommerce marketplace platform.

Key Responsibilities

Develop, maintain, and optimize backend applications for ecommerce and multi-vendor marketplace platforms.

Design and build secure and scalable REST APIs for web applications, mobile apps, and third-party integrations.

Architect and maintain clean, modular, and scalable backend systems.

Integrate and maintain payment gateways, shipping APIs, and external services.

Design, manage, and optimize MySQL and MongoDB databases.

Ensure backend performance, scalability, and security best practices.

Debug, troubleshoot, and resolve complex backend issues.

Collaborate with frontend, SEO, and operations teams to ensure smooth platform performance.

Implement automation workflows and backend improvements.

Manage deployments and server configurations.

Required Skills and Qualifications

Strong experience in PHP frameworks such as Laravel or CodeIgniter.

Hands-on experience with Node.js.

Strong command over MySQL, SQL, and MongoDB.

Solid experience in REST API development and third-party integrations.

Experience working on ecommerce or multi-vendor marketplace platforms.

Understanding of server management and deployment processes.

Knowledge of SEO-friendly backend architecture.

Strong analytical thinking and problem-solving skills.

Ability to work in a fast-paced and deadline-driven environment.

Good to Have

Experience building scalable ecommerce marketplace systems.

Experience with Docker-based deployments.

Knowledge of caching mechanisms and performance optimization.

Familiarity with Git or other version control systems.

Why Join Bharat Agrolink

Opportunity to work on a rapidly growing ecommerce marketplace.

Take ownership of backend architecture and core platform systems.

Be part of a performance-driven and growth-oriented startup culture.

Strong career growth opportunities while working on real-world scalable products.

• Good foundation in CS fundamentals – algorithms, data structures
• Strong design and data modeling skills
• Good understanding of SQL and NOSQL databases
• Good concepts of object oriented programming and design patterns

• Location - Remote 

  Good to have

  • Familiarity with microservices design and testing
  • Familiarity with docker based setup
  • Prior experience in designing scalable microservices
  • Familiarity with cloud infrastructure and cloud deployment
  • Familiarity with CI/ CD pipelines