Backend Developer (Sr. Engineer / Lead)

Job Title: Golang Developer

Location: Kolkata

Job Type: Full-time

Working Days: 5 Days (Rotational off)

About the Role:

We are seeking a skilled Golang Developer with experience in Golang, Node.js, WebSocket

communication, and API development. In this role, you will work closely with our development

team to design, develop, and maintain high-performance backend systems and real-time

applications.

Key Responsibilities:

 Design, build, and maintain efficient, reusable, and reliable Golang code.

 Develop scalable APIs and microservices.

 Integrate and build real-time communication using WebSocket protocols.

 Collaborate with frontend developers and other team members to establish objectives

and design more functional, cohesive systems.

 Write clean, maintainable, and well-documented code.

 Optimize applications for maximum performance, scalability, and security.

 Participate in code reviews, contribute to team knowledge, and continuously improve

development processes.

 Troubleshoot, debug, and upgrade existing systems.

 Occasionally work with Node.js services and modules when needed.

Required Skills and Qualifications:

 Min 3+ years of experience in backend development with Golang.

 Solid understanding of Node.js and JavaScript/TypeScript.

 Hands-on experience with WebSocket integration and real-time applications.

 Strong knowledge of RESTful APIs, API design principles, and API documentation. Experience with relational and NoSQL databases (e.g., MySQL, PostgreSQL, MongoDB).

 Good understanding of concurrent programming and microservices architecture.

 Familiarity with cloud platforms (AWS, GCP, Azure) is a plus.

 Knowledge of containerization tools like Docker and Kubernetes is a plus.

 Strong problem-solving skills, attention to detail, and a proactive attitude.

• Work closely with design, product management, and front-end teams to create REST APIs using NestJS
• Write reusable, testable, and efficient code
• Design and implementation of low-latency, high-availability, and performant applications
• Work on the implementation of security and data protection
• Review and optimize the app usage by monitoring key metrics and rectifying the issues proactively

• 1+ years of experience in NodeJS-based frameworks like NestJS, and microservices-based architecture is a bonus.
• Understanding of OOPS concepts, persistence, threading, queuing, and caching.
• Thorough knowledge of designing, implementing and scaling relational and document-based databases
• A love for systems and an ability to think through and plan for their life cycles, edge cases, interactions, and failure modes
• First principles thinking, Excellent problem-solving ability
• A good all-rounder with a can-do, startup mentality

• Experience with ReactJS
• Cloud deployment and scaling experience

• Experience in designing and developing web-based applications using Java, J2EE, Web Services, MVC framework, Servlets Spring, Hibernate, Struts, REST, MYSQL.
• Experience in Database application programming for MySQL server using
  Stored Procedures, Triggers, Views etc.
• Experienced in implementing presentation layer using JSP, HTML, CSS, Ajax, JQuery. Java script.
• Formulated AWS (EC2, S3, Elastic Beanstalk, RDS, Route53, SG, ELB, IAM, CloudWatch). (ABOVE ONLY NEEDED FOR 7+ EXPERIENCE)
• Experienced in Analysis, Design, Development, Integration, Deployment
  and Maintenance of Web services, Client Server and Web based applications.
• Well versed with Agile development process, Scrum.
• Good knowledge in version control system tools like GIT.
• Ability to take independent responsibility as well as ability to contribute and be a productive team member.
• Excellent analytical, logical and programming skills, Self-Motivated, Self-Starter, Team Player can work with minimal supervision with effective Communication
  skills and Organizational skills combined with attention and Time management skills.

Role Description:

As a Lead Backend Engineer , you will be responsible for designing and deploying scalable, highly available, and fault-tolerant systems for Radiusagent. Experience as a Tech Lead, managing tasks with back-end engineers while coding themselves will be a bonus point for the ideal candidate.

Responsibilities will include-

• You will contribute to all aspects of an agile software development lifecycle including design, architecture, development, documentation, testing, and operations.
• You will build cutting-edge scalable systems by writing simple and efficient code.
• You will push your design and architecture limits for new product development.
• You will ensure compliance with the build/release and configuration management process.

Skills needed:

• be able to design and build modules from ground up
• proficient in any one programming language out of php/golang/node/python/javascript/java/ruby and ability to pick up others
• experience with mysql/postgres/mongodb/couchdb
• experience  with redis/memcached
• experience with rabbitmq / kafka
• experience in having written cron jobs, troubleshooting downtime
• ability to work with ambiguous requirements
• good understanding of OS concepts

Nice to haves:

• experience with managing VMs' on aws/gcp/digitalocean 
• experience with docker/kubernetes
• experience elasticsearch or lucene

Senior Software Engineer (Python)

Job description

Fulfil’s software engineers develop the next-generation technologies that change how millions of customer orders are fulfilled by merchants. Our products need to handle information at massive scale. We're looking for engineers who bring fresh ideas from all areas into our technology.

As a senior software engineer, you will work on our python based ORM and applications that scales to handle millions of transactions every hour. This is mission critical software and your primary focus will be building robust and scalable solutions that are easy to maintain.

In this role, you will be collaborating closely with the rest of the team working on different layers of infrastructure in an international environment. Therefore, a commitment to collaborative problem solving, sophisticated design, and quality product are important.

What You’ll Do:

• Own definition and implementation of API interfaces (REST and GraphQL). We take pride in our 100% open API with over 600 endpoints.
• Implement simple solutions to complex business logic that enables our merchants to manage financials, orders and shipments across millions of transactions.
• Build reusable components and packages for future use.
• Translate specs and user stories into reviewable, test covered patches.
• Peer review code and refactor existing code.
• Integrate with our eCommerce partners (Shopify, BigCommerce, Amazon), shipping partners (UPS, USPS, FedEx, DHL) and EDI.
• Manage Kubernetes and Docker based global deployment of our infrastructure.

Requirements

We’re Looking for Someone With:

• Experience working with ORMs like SQLAlchemy or Django
• Experience with SQL and databases (Postgres preferred)
• Experience in developing large server side applications and microservices
• Ability to create high quality code
• Experience with python testing tools (pytest) and test automation
• Familiarity with code versioning tools like GIT
• Strong sense of ownership and leadership quality
• Experienced in the tools of our web stack
• Python
• Celery
• Postgres
• Redis
• RabbitMQ

Nice to Haves:

• Prior experience at a growth stage Internet/Software company
• Experience with ReactJS, Google Cloud, Heroku
• Cloud deployment and scaling experience

About Us:

Fulfil.io helps high growth, high volume merchants simplify operations and scale for growth. With the rise in omni-channel commerce, Fulfil was founded with the simple idea that merchant operations need to be simplified in order to deliver amazing retail experiences. Fulfil enables businesses to turn their back office operations into an accelerator for growth by integrating order management, inventory management, warehouse management, vendor/supplier management, wholesale, manufacturing, financials and customer service, into one seamless solution. We believe merchants should love their operations platform, and we work hard to make that happen every single day. Fulfil.io is a trusted solution for brands like EndySleep, Mejuri, Lie-Nielson Toolworks, and many more.  

Fulfil.io is a venture backed technology company with offices in San Francisco, Toronto, and Bangalore. The team is made up of people who want to feel challenged at work, be the best at their craft and learn from one another. We come from different backgrounds and experiences, all passionate about the work we do, the team we do it with, and the customers we do it for. Join us in our journey to simplify operations and empower merchants around the world!