Sr . Software Engineer

We are looking for a Python Backend Developer to design, build, and maintain scalable backend services and APIs. The role involves working with modern Python frameworks, databases (SQL and NoSQL), and building well-tested, production-grade systems.

You will collaborate closely with frontend developers, AI/ML engineers, and system architects to deliver reliable and high-performance backend solutions.

Key Responsibilities

• Design, develop, and maintain backend services using Python
• Build and maintain RESTful APIs using FastAPI
• Design efficient data models and queries using MongoDB and SQL databases (PostgreSQL/MySQL)
• Ensure high performance, security, and scalability of backend systems
• Write unit tests, integration tests, and API tests to ensure code reliability
• Debug, troubleshoot, and resolve production issues
• Follow clean code practices, documentation, and version control workflows
• Participate in code reviews and contribute to technical discussions
• Work closely with cross-functional teams to translate requirements into technical solutions

Required Skills & Qualifications

Technical Skills

• Strong proficiency in Python
• Hands-on experience with FastAPI
• Experience with MongoDB (schema design, indexing, aggregation)
• Solid understanding of SQL databases and relational data modelling
• Experience writing and maintaining automated tests
• Unit testing (e.g., pytest)
• API testing
• Understanding of REST API design principles
• Familiarity with Git and collaborative development workflows

Good to Have

• Experience with async programming in Python (async/await)
• Knowledge of ORMs/ODMs (SQLAlchemy, Tortoise, Motor, etc.)
• Basic understanding of authentication & authorisation (JWT, OAuth)
• Exposure to Docker / containerised environments
• Experience working in Agile/Scrum teams

What We Value

• Strong problem-solving and debugging skills
• Attention to detail and commitment to quality
• Ability to write testable, maintainable, and well-documented code
• Ownership mindset and willingness to learn
• Teamwork

What We Offer

• Opportunity to work on real-world, production systems
• Technically challenging problems and ownership of components
• Collaborative engineering culture

The requirements are as follows:

1) Familiar with the the Django REST API Framework.

2) Experience with the FAST API framework will be a plus

3) Strong grasp of basic python programming concepts ( We do ask a lot of questions on this on our interviews :) )

4) Experience with databases like MongoDB , Postgres , Elasticsearch , REDIS will be a plus

5) Experience with any ML library will be a plus.

6) Familiarity with using git , writing unit test cases for all code written and CI/CD concepts will be a plus as well.

7) Familiar with basic code patterns like MVC.

8) Grasp on basic data structures.

You can contact me on nine three one six one two zero one three two

Role & Responsibilities

As a Founding Engineer, you'll join the engineering team during an exciting growth phase, contributing to a platform that handles complex financial operations for B2B companies. You'll work on building scalable systems that automate billing, usage metering, revenue recognition, and financial reporting—directly impacting how businesses manage their revenue operations.

This role is ideal for someone who thrives in a dynamic startup environment where requirements evolve quickly and problems require creative solutions. You'll work on diverse technical challenges, from API development to external integrations, while collaborating with senior engineers, product managers, and customer success teams.

Key Responsibilities

• Build core platform features: Develop robust APIs, services, and integrations that power billing automation and revenue recognition capabilities.
• Work across the full stack: Contribute to backend services and frontend interfaces to ensure seamless user experiences.
• Implement critical integrations: Connect the platform with external systems including CRMs, data warehouses, ERPs, and payment processors.
• Optimize for scale: Design systems that handle complex pricing models, high-volume usage data, and real-time financial calculations.
• Drive quality and best practices: Write clean, maintainable code and participate in code reviews and architectural discussions.
• Solve complex problems: Debug issues across the stack and collaborate with cross-functional teams to address evolving client needs.

The Impact You'll Make

• Power business growth: Enable fast-growing B2B companies to scale billing and revenue operations efficiently.
• Build critical financial infrastructure: Contribute to systems handling high-value transactions with accuracy and compliance.
• Shape product direction: Join during a scaling phase where your contributions directly impact product evolution and customer success.
• Accelerate your expertise: Gain deep exposure to financial systems, B2B SaaS operations, and enterprise-grade software development.
• Drive the future of B2B commerce: Help build infrastructure supporting next-generation pricing models, from usage-based to value-based billing.

Ideal Candidate Profile

Experience

• 5+ years of hands-on Backend Engineering experience building scalable, production-grade systems.
• Strong backend development experience using one or more frameworks: FastAPI / Django (Python), Spring (Java), or Express (Node.js).
• Deep understanding of relevant libraries, tools, and best practices within the chosen backend framework.
• Strong experience with databases (SQL & NoSQL), including efficient data modeling and performance optimization.
• Proven experience designing, building, and maintaining APIs, services, and backend systems with solid system design and clean code practices.

Domain

• Experience with financial systems, billing platforms, or fintech applications is highly preferred.

Company Background

• Experience working in product companies or startups (preferably Series A to Series D).

Education

• Candidates from Tier 1 engineering institutes (IITs, BITS, etc.) are highly preferred.

Who we are: My AI Client is building the foundational platform for the "agentic economy," moving beyond simple chatbots to create an ecosystem for autonomous AI agents and they aim to provide tools for developers to launch, manage, and monetize AI agents as "digital coworkers."

The Challenge

The current AI stack is fragmented, leading to issues with multimodal data, silent webhook failures, unpredictable token usage, and nascent agent-to-agent collaboration. My AI Client is building a unified, robust backend to resolve these issues for the developer community.

Your Mission

As a foundational member of the backend team, you will architect core systems, focusing on:

• Agent Nervous System: Designing agent-to-agent messaging, lifecycle management, and high-concurrency, low-latency communication.
• Multimodal Chaos Taming: Engineering systems to process and understand real-time images, audio, video, and text.
• Bulletproof Systems: Developing secure, observable webhook systems with robust billing, metering, and real-time payment pipelines.

What You'll Bring

• My AI Client seeks an experienced engineer comfortable with complex systems and ambiguity.

Core Experience:

● Typically 3 to 5 years of experience in backend engineering roles.

● Expertise in Python, especially with async frameworks like FastAPI.

● Strong command of Docker and cloud deployment (AWS, Cloud Run, or similar).

● Proven experience designing and building microservice or agent-based architectures.

Specialized Experience (Ideal):

• Real-Time Systems: Experience with real-time media transmission like WebRTC, WebSockets and ways to process them.
• Scalable Systems: Experience in building scalable, fault-tolerant systems with a strong understanding of observability, monitoring, and alerting best practices.
• Reliable Webhooks: Knowledge of scalable webhook infrastructure with retry logic, backoffs, and security.
• Data Processing: Experience with multimodal data (e.g., OCR, audio transcription, video chunking with FFmpeg/OpenCV).
• Payments & Metering: Familiarity with usage-based billing systems or token-based ledgers.

Your Impact

• The systems designed by this role will form the foundation for:
• Thousands of AI agents for major partners across chat, video, and APIs.
• A new creator economy enabling developers to earn revenue through agents.
• The overall speed, security, and scalability of my client’s AI platform.

Why Join Us?

• Opportunity to solve hard problems with clean, scalable code.
• Small, fast-paced team with high ownership and zero micromanagement.
• Belief in platform engineering as a craft and care for developer experience.
• Conviction that AI agents are the future, and a desire to build their powering platform.
• Dynamic, collaborative in-office work environment in Bengaluru in a Hybrid setup (weekly 2 days from office)
• Meaningful equity in a growing, well-backed company.
• Direct work with founders and engineers from top AI companies.
• A real voice in architectural and product decisions.
• Opportunity to solve cutting-edge problems with no legacy code.

Ready to Build the Future?

My AI Client is building the core platform for the next software paradigm. Interested candidates are encouraged to apply with their GitHub, resume, or anything that showcases their thinking.

Job responsibility The Lead Developer contributes, to create a customer’s solution, in the building phase of the software development lifecycle. The Software Engineer is responsible for performing the detailed design of application and technical architecture components and classes in accordance to the specification provided by the Solution Architect, for coding of SW components, and for the early testing phases (component testing), and system testing support

Hands on experience in Java, Python, scripting
- Design, implement, deploy and support web-based applications and web services using server technologies stacks that include Java, MySQL
- Experience in Java/J2EE using web frameworks Play or Spring boot, REST API Development and ORM (JPA, Hibernate eBean etc.)
- In depth knowledge of Design patterns and Data structures
- Databases - MySQL, Oracle, SQL
- Solid understanding of concepts like Web Services, SOA, REST APIs, Message Queue, Caching, Distributed/Scalable Architecture
- Secure application development best practices, such as OWASP
- Document and maintain all design documents and involve in review process.
- Experienced problem solving and debugging skills.
- Good verbal and written communication and interpersonal skills
- Experience in Agile methodology is added advantage
- Knowledge of Cloud Knowledge /Azure
- Must know about Unix knowledge
- experience in Elastic search

Rejolut is one of the award-winning fastest-growing emerging tech company which is working on leading technology like Blockchian, ML & AI, Complex mobile & web apps, IoT etc.

The ideal candidate will be responsible for developing a highly scalable and secure code.

Responsibilities:-
-Able to take the Extreme Ownership of modules/product/projects
-Able to learn & implement new technology/framework/library at God Speed
-Able to come with an optimal solution for the business problem
-Can handle calls with the client & customer to know their feedback
-Writing clean code & able to dig into other's code or open-source code
-Build pixel-perfect, buttery smooth UIs across both mobile platforms.

- Maintain product roadmap, release schedules, and architectural standards that ensure alignment with business objectives.

Desired Candidate Profile:-

- Represent the technological agenda in staff meetings and when making hiring decisions
- Flexible to adapting & introducing new and latest technologies to the organization
- Maintain current knowledge of technology landscape and developments
- Innovation & Optimizing R&D.
- Defining the software technology strategy, architecture, and road-map.
- Would love to do more coding yourself, but accept that you can bring the most value by helping others to excel.
- Should have built large scale applications with modern web frameworks & technologies
-Should be a fast thinker, hands-on manager, and strong communicator and think and act like an entrepreneur
-Consolidate our technology platforms and create plans for each Track, analyze and monitor technology performance metrics
-Take the initiative in thought leadership, innovation, and creativity
-Spearhead IT projects to increase our market reach and improve our USP
-Oversee all system design and changes in system architecture
-Technical knowledge (NOT All but would be happy to take someone with max. Skills knowledge)
-Fullstack (Web), Python, Machine Learning, BlockChain, RoR, ReactJS, NodeJS, mean stack, MernStack, Front End, Mobility, ReactNative, React JS, Javascript, etc

Culture

- Fast-paced, intellectually stimulating, steep learning, and growth

- Close-knit, hardworking, supportive colleagues

- Challenging work

- Flat organization with no hierarchy

- If you like problem-solving, and love the latest technology, there are very few better places

How we are different 
 -We are a young and dynamic team who are obsessed with solving the business problem at scale -We are a technology agnostic company who focus more on finding the optimal solution to the business problem rather than technology

 Why to join us
 -We provide a huge learning curve. Spending 1.5-2 years with us will put you 3 years ahead in the career
-We work only on cutting edge technology like React, React Native, Flutter, NodeJS, Python, Go, Svelte, ELM
-There are two technology Co-founder in the company who are pretty much hands-on and have earlier bult the Consumer application which is downloaded millions of time and are in leadership position in copanies like Samsung, Purplle, Loylty Rewardz
-Get mentored by the best in the industry
-Flexible working hours
-Perks best in the industry

• Part of the core team responsible for powering the various apps and moving parts of the product
• Design, build and own key technology decisions and implementations
• Wear multiple hats - that of an architect, developer, or product owner
• Collaborate with other team members to find optimal solutions and engineering workarounds based on resource/time constraints
• Communicate development status and features to the rest of the team members
• Manage interactions with designers, testers, and other developers

Required Skills :

• 4-6 years of overall software development experience
• 2+ years of development experience with Ruby on Rails
• Experience with support of high-availability, high-performance, customer-facing web applications
• Expert in configuring and deploying multiple rails applications quickly
• Experience with collaborative code development in small agile teams and managing releases (Git, Continuous Integration, Capistrano)
• Experience building internal and external APIs and RESTful web services
• Strong foundation in Database ( SQL / Postgres )
• Experience deploying and managing applications on cloud-based infrastructure (Heroku/AWS)
• Outstanding understanding of software design and architecture

It will be good if you also have:

• Worked in a web startup before and been part of the core development during a high growth phase
• Practical experience with building scalable, high availability, and high-performance systems
• Hands-on background with agile development practices including test-driven development and scrums
• Contributed to open-source projects on Github
• Familiarity with a variety of programming languages and development tools

• B Tech/BE or M.Tech/ME in Computer Science or equivalent from a reputed college.
• Experience level of 7+ years in building large scale applications.
• Strong problem solving skills, data structures and algorithms.
• Experience with distributed systems handling large amount of data.
• Excellent coding skills in Java / Python / Node / Go.
• Very good understanding of Web Technologies.
• Very good understanding of any RDBMS and/or messaging.