




lives of API developers and consumers easier. If you love thinking big and delving deep and
enjoy envisioning truly elegant solutions, this role is definitely for you.
What you will be Doing
- You will abstract away complex data interactions with easy-to-use APIs that will power several
mobile and web applications.
- You will also own, scale, and maintain the computational and storage infrastructure for the
various micro-services and long-running jobs, designed and implemented by you and the team.
- We will look to you to make key decisions on the technology stack, architecture, networking,
and security. We love working with bleeding-edge technology, especially if it improves the
malleability, and simplicity of our deliverables.
What you need
- The ideal Backend Engineers are polyglots who are fluent in HTTP and core CS concepts such
as algorithms, data structures, and programming paradigms, and always pick the right tools for
the right job.
- They have a keen eye for common security vulnerabilities and how to act on them (example:
DDOS attacks, SQL Injection etc.).
- They understand what it takes to work in a startup environment and know when to trade
performance for simplicity.
- They fail fast, learn faster, and execute in time.
- Strong communication skills, get-things-done attitude, and empathy
- Strong sense of ownership, drive and obsessive attention to detail.
- Comfortable with iterative development practices and code reviews
- Previous experience as part of a product-oriented team is a plus
Technical Skillsets:
NodeJS + Javascript, GoLang, Typescript + Nodejs, Clojure/Haskell/F#/Scala
(languages/environments)
Koa, Express, Play (frameworks)
Asynchronous Programming Frameworks (Akka, Nodejs, Tornado)
MongoDB, postgres, Bigtable, Dynamo (databases)
Apache Kafka, NATS, RabbitMQ, ZeroMQ (queues)
FunctionalProgramming, FRP (functional reactive)
microservices, multi-tenant, distributed-systems, distributed-computing, event-sourcing
Good to have Skillsets:
Clojure/Haskell/F#/Scala
Apache Kafka, NATS
FunctionalProgramming, FRP (functional reactive)
event-sourcing
Koa
Why you should consider this role seriously?
- We have an audacious vision of helping companies fight counterfeiting and managing their
supply chain more efficiently
- We have built a product and solved problems for some of the largest brands in the country and
tested platform at scale (With our tags present in over 50 Million products already). We have
plans to grow 10x in the next 1 year
- Ownership of key problems. Fast-paced environment
- We are a well-balanced team of experienced entrepreneurs and are backed by top investors
across India and the Silicon Valley (Venture Highway, Startup Buddy etc.)
- Competitive market salary
- Opportunity to work directly with the CEO, COO, CTO of the company
- A chance to interact with top-notch executives from multiple industries
- Open vacation policy (and we really mean it!)
- Open Pantry
- As a team, we love to travel :). An off-site every quarter

About O4S
About
Connect with the team
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About the Role:
We are seeking a skilled and driven Backend Developer with expertise in Python (Django/FastAPI) and Node.js (TypeScript) to join our team. The ideal candidate will have experience in database design (RDBMS and NoSQL), REST API and GraphQL development, cloud services, and AI-driven applications. You will be responsible for designing and implementing scalable backend solutions, ensuring high performance, security, and reliability.
If you’re passionate about backend development, Generative AI, and data engineering, this is the role for you!
Key Responsibilities:
Backend Development:
- Develop and maintain robust, scalable backend services using Node.js (TypeScript) and Python (Django/FastAPI).
- Build APIs with REST and GraphQL, ensuring high security and performance.
- Implement authentication mechanisms such as OAuth2.0, SAML, JWT, MFA, and passkeys (optional).
- Research and integrate Generative AI (Gen AI) models and OpenAI APIs into backend systems.
Database & Data Engineering:
- Design and optimize schemas for both relational (PostgreSQL, YSQL) and NoSQL (DynamoDB, MongoDB) databases.
- Work with Redshift, BigQuery, and Snowflake to manage large-scale data processing.
- Develop ETL pipelines for data ingestion and transformation.
- Utilize Apache Airflow for workflow automation.
Cloud Services & Serverless Architecture:
- Work extensively with AWS Cloud services, and optionally Azure and GCP.
- Design and implement serverless architectures and event-driven systems using frameworks like AWS Lambda or equivalent on Azure/GCP.
- Configure and manage webhooks for event notifications and integrations.
- Integrate Apache Pulsar for real-time event streaming and messaging.
Programming & AI Integration:
- Apply design patterns, SOLID principles, and functional programming practices.
- Develop Python-based AI/ML solutions, leveraging Django/FastAPI for backend services.
- Manage AI/ML environments using Conda.
DevOps & Deployment:
- Utilize Docker and Kubernetes (K8s) for containerization and orchestration.
- Collaborate with DevOps teams for CI/CD pipelines and scalable deployments.
Tools & Utilities:
- Use Postman, Swagger, and cURL for API testing and documentation.
- Demonstrate strong knowledge of Unix commands for troubleshooting and development.
- Work with Git for versioning and code management.
Key Skills & Qualifications:
Must-Have:
✔ Proficiency in Python (Django/FastAPI) and Node.js (TypeScript).
✔ Experience with NestJS framework.
✔ Expertise in RDBMS and NoSQL database design and optimization.
✔ Hands-on experience with REST API and GraphQL development.
✔ Familiarity with authentication protocols such as OAuth2.0, SAML, JWT, and MFA.
✔ Strong understanding of AWS Cloud Services and Serverless Architecture.
✔ Experience with Gen AI, OpenAI APIs, and AI model integration.
✔ Hands-on knowledge of Python and Conda environments.
✔ Expertise in Redshift, BigQuery, Snowflake, and Apache Airflow for Data Engineering.
✔ Exposure to Apache Pulsar for event streaming.
Nice-to-Have:
➕ Exposure to Azure and GCP serverless frameworks.
➕ Knowledge of webhooks for event handling.
➕ Experience with passkeys as an authentication option.
Soft Skills:
✅ Problem-solving mindset with a passion for tackling complex challenges.
✅ Ability to learn and adapt to new tools, frameworks, and programming languages.
✅ Collaborative attitude and strong communication skills.
What We Offer:
💰 Competitive compensation and benefits package.
🚀 Opportunity to work with cutting-edge technologies in a fast-paced environment.
📚 A culture of learning, growth, and collaboration.
🌍 Exposure to large-scale systems, AI/ML integrations, and exciting technical challenges.

Must have - Strong python

Job description
Ruby on Rails Developer Responsibilities :
- Designing and developing new web applications.
- Maintaining and troubleshooting existing web applications.
- Writing and maintaining reliable Ruby code.
- Integrating data storage solutions.
- Creating back-end components.
- Identifying and fixing bottlenecks and bugs.
- Integrating user-facing elements designed by the front-end team.
- Connecting applications with additional web servers.
- Maintaining APIs.
Ruby on Rails Developer Requirements :
- Bachelor's degree in Computer Science, Computer Engineering, or related field.
- Experience working with Ruby on Rails as well as libraries like Resque and RSpec.
- Ability to write clean Ruby code.
- Proficiency with code versioning tools including Git, Github, SVN, and Mercurial.


Desired Experience
3+ years
Job Description
What You’ll Do
- Design financial systems for scale. Measure, plan, iterate.
- Writing reusable, testable, and efficient code
- Design and implementation of low-latency, high-availability, and performant applications
- Setup and own the engineering architectures built around event sourcing, application sharding, database sharding, service communication mesh, etc.
- The tech: Go, Google Cloud Spanner, Kafka, Redis
What you bring to the table
- 3+ years of experience. Relevant experience is preferred.
- Knowledge of 2 common programming languages - Python & Go / Java & Node / Rust
- Comfortable in linux command line, AWS or GCP
- Strong unit test and debugging skills
- Great communication skills
Bonus if you have…
- Love building great products and engineering systems from scratch
- Are a Self-starter, Hustler and Curious to Learn
- Have an understanding of fundamental design principles behind a scalable application
- Thrive in an early-stage startup environment with less stability and more ambiguity
- Have an interest in financial products and/or cryptocurrency
Job Description: Core Java Developer
Company: Mobile Programming LLC
Location: Pune (Remote work available)
Salary: Up to 16 LPA
Position: Core Java Developer
Responsibilities:
- Design, develop, and maintain Java-based applications using Core Java and Spring Boot frameworks.
- Collaborate with cross-functional teams to deliver high-quality software solutions.
- Conduct code reviews and troubleshoot/debug complex issues.
- Optimize application performance and stay updated with industry trends.
Requirements:
- Minimum 6 years of hands-on Core Java development experience.
- Strong proficiency in Spring Boot framework.
- Solid understanding of OOP principles, web development (HTML/CSS/JavaScript), RESTful web services, and SQL.
- Experience with Git and problem-solving skills.
- Excellent communication skills and ability to work independently and as part of a team.
- Bachelor's or Master's degree in Computer Science or a related field.
Note: Immediate joiners required. Please include your resume and relevant code samples/projects when applying.

We are looking for 2 - 10 years experienced Ruby on Rails and VueJS developer responsible for building
applications, including anything from complex groups of back-end micro-services to command line utilities and
data processing scripts. Your primary responsibility will be to design and develop these applications, and to
coordinate with the rest of the team working on different layers of the infrastructure. Thus, a commitment to
collaborative problem solving, sophisticated design, and building quality products is essential.
Key Duties & Responsibilities:
• Design, develop, and implement new modules and APIs for the BEAM Product
• Plan, build and launch features for our products
• Write unit, functional, and integration tests
• Estimate development tasks and meet deadline
• Collaborate with engineering, QA, and product design team members
• Scale our applications as our user base grows
Mandatory Skills & Experience:
Ability to work & develop in Linux environment
• A solid understanding of Ruby
• 5+ years of web application engineering experience with Ruby on Rails, PostgreSQL, HTML, CSS,
JavaScript, Responsive Design, Caching
• 1+ years of experience with a front-end framework (Vue.js & GIT)
• Solid 2+ plus years of web dev experience building web UI/UX interactions.
• 5+ years of experience improving the performance of Ruby on Rails applications with Memcached &
background job processing frameworks (Sidekiq, Resque etc.)
• Hands on experience in deploying applications using AWS Infrastructure using Capistrano automated
deployment.
Backend Developer
About Us
It is a stealth mode startup founded by IIT/NIT alumni who held leadership positions in companies like MindTickle and Browserstack. We have a grand vision of disrupting how companies buy and sell from each other. We are working with early customers to build an enterprise-grade product that will be GA this year. It is backed by tier 1 VCs and angel investors from India and Silicon Valley.
Job Description
We are looking for a Backend Engineer to work closely with the founding team. We are looking for a 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.
Responsibilities
- Develop platform and infra stack from scratch
- Writing reusable, testable, and efficient code
- Compile and analyze data, processes, and codes to troubleshoot problems and identify areas for improvement.
- Optimize application for maximum speed and scalability.
- Implementation of security and data protection
- Collaborating with the front-end developers and other team members to establish objectives and design more functional, cohesive codes to enhance the user experience.
- Developing ideas for new programs, products, or features by monitoring industry developments and trends.
- Recording data and reporting it to proper parties, such as clients or leadership.
- Participating in continuing education and training to remain current on best practices, learn new technologies, and better assist other team members.
- Taking lead on projects, as needed.
Technology Skills
- Proven work experience as a NodeJs Backend developer and frameworks available with it like Express, Apollo Graphql. Typescript knowledge is a plus
- In-depth understanding of the entire web development process (design, development and deployment)
- Hands-on with various Infrastructure pieces like databases, message queues/brokers
- Familiarity with Unit Testing Frameworks, UI Testing, Monorepos and Graphql principles
- Knowledge of Alerting and Monitoring tools.
- Implementing automated testing platforms and unit tests
- Proficient understanding of code versioning tools, such as Git
- Integration of multiple data sources and databases into one system.
- Prior experience of the AWS cloud, knowledge about the Salesforce environment is a plus.
- Excellent project and time management skills.
Soft Skills
- Obsessed with best practices, structuring, documentation and have an eye for detail.
- Self starter with a high level of drive and commitment.
- High energy and drive to work in a startup environment.
- Conceptual thinking, flexibility and ability to juggle with multiple responsibilities.
- Ability to work under pressure and confidence to deal with complex issues.
- Good communication skills.
- Hands-on and detail oriented.
Location: Pune
Candidate profile : 3-6 years of experience in Backend Development
Role
As one of the senior members of the backend development team you will be
responsible for architecting and setting the standards for building our core
backend/microservices. Also, you will be responsible for shaping up the entire system for scale
and collaborating extensively with the frontend and design teams to create the best consumer
experiences.
Responsibilities
● Develop microservices that will be used by the frontend through API endpoints.
● Translate business requirements into high quality code.
● Ensure that the code is deployed in a secure and scalable fashion.
● Focus on code maintainability and performance of application.
● Provide technical advice and assists in solving programming problems.
● Enhance Analytics and overall backend architecture for better performance.
Requirements
● 4+ years of backend/full-stack development experience
● 1+ years of experience on NodeJS
● 1+ years experience in building APIs in a microservice architecture
● Has experience managing other developers, recruiting and training.
● Experience in PHP is a plus
● Experience with AWS services such as Lambda, CloudWatch, CloudFront
● Has experience in code reviewing/being the gatekeeper for an entire project
● Experience with RabbitMQ or similar queuing system
● Experience with Redis/ElasticSearch is a plus
● Familiarity with CI/CD pipeline tools like Jenkins
● Good knowledge of working with Git
● A knack for benchmarking and optimization



