Full-stack Python Architect / Lead

We are looking for a skilled Python Developer to design, develop, and maintain robust backend systems. You will be responsible for building scalable web applications using the Flask micro-framework and managing high-performance NoSQL data storage with MongoDB. Your role involves creating RESTful APIs, optimizing database queries, and ensuring seamless integration between the backend logic and frontend components.

Key Responsibilities

• API Development: Design and implement scalable, secure RESTful APIs using Flask.
• Database Management: Architect and maintain MongoDB schemas; develop complex aggregation pipelines and optimize query performance.
• Backend Logic: Write clean, efficient, and testable Python code to handle server-side logic and data processing.
• Integration: Integrate third-party services and internal data sources using libraries like Requests or Flask-PyMongo.
• Performance Optimization: Identify and resolve bottlenecks in the application and database layers to ensure low latency.
• Testing & Security: Implement unit tests (using pytest or unittest) and follow security best practices (OAuth2, JWT, data encryption).
• Collaboration: Work closely with frontend developers to integrate user-facing elements and with DevOps to support deployment.

Required Technical Skills

CategoryRequirementsLanguageExpert-level Python (OOP, decorators, generators, and async programming).Frameworks Strong experience with Flask (routing, blueprints, middleware).DatabaseProficiency in MongoDB (BSON, indexing, sharding, and aggregation framework).ODMs/DriversExperience with PyMongo or MongoEngine.ArchitectureSolid understanding of RESTful API design and Microservices.Tools/DevOpsVersion control with Git; familiarity with Docker and CI/CD pipelines

Job Summary: We are seeking a highly skilled Full-stack Developer to join our dynamic team as a Delivery Module Lead. The ideal candidate will possess strong expertise in Python and front-end technologies, enabling them to design, develop, and maintain robust web applications. This role requires a proactive individual who can collaborate effectively with cross-functional teams to deliver high-quality software solutions that meet business needs.

• Proficient in Python programming language.
• Strong knowledge of front-end technologies such as HTML, CSS, and JavaScript.
• Experience with front-end frameworks like React, Angular, or Vue.js.
• Familiarity with back-end frameworks such as Django or Flask.
• Understanding of RESTful APIs and web services.
• Experience with version control systems, preferably Git.

About the Company

Mellow Vault is building a next-generation technology and talent ecosystem focused on scalable software solutions and high-performance code. The team works across web development, cloud technologies, and modern software engineering stacks to create reliable digital products. This opportunity is intended for early-career developers and fresh graduates who want to strengthen their engineering capabilities while contributing to meaningful digital products in a collaborative environment.

Responsibilities

• Write clean, maintainable, efficient code using Python, Java, JavaScript, TypeScript, C++, or related technologies.
• Support the design, development, testing, and deployment of APIs, web applications, and data services.
• Assist with debugging, defect resolution, application performance improvements, and technical troubleshooting.
• Participate in daily standups, code reviews, sprint planning, and agile development practices.
• Collaborate with senior developers and cross-functional teammates to understand requirements and follow sound implementation standards.

Requirements

• Strong foundational knowledge of data structures, algorithms, and object-oriented programming principles.
• Familiarity with at least one modern programming language, such as Python, Java, JavaScript, TypeScript, or C++.
• Basic understanding of HTML, CSS, REST APIs, and SQL or NoSQL database concepts.
• Working familiarity with Git or GitHub and standard software development workflows.
• Good problem-solving ability, communication skills, curiosity, and a strong willingness to learn new technologies.
• This role is suitable for fresh graduates and early-career candidates with 0 years of experience.

About the Role

We are looking for a motivated Software Developer to join our team and help design, develop, test, and maintain reliable software applications. The ideal candidate should have strong programming fundamentals, problem-solving skills, and a willingness to learn new technologies.

Key Responsibilities

• Develop, test, and maintain web and software applications.
• Write clean, scalable, and well-documented code.
• Work with frontend and backend technologies to build new features.
• Identify and fix bugs, performance issues, and technical problems.
• Integrate APIs and third-party services when required.
• Work with databases and maintain data integrity.
• Collaborate with designers, developers, and other team members.
• Participate in code reviews and follow software development best practices.
• Stay updated with emerging technologies and development tools.

Required Skills

• Strong knowledge of HTML, CSS, and JavaScript.
• Knowledge of at least one programming language such as Python, Java, PHP, C++, or JavaScript/Node.js.
• Basic understanding of databases such as MySQL, PostgreSQL, or MongoDB.
• Familiarity with REST APIs and Git/GitHub.
• Good understanding of software development and debugging.
• Strong logical thinking and problem-solving abilities.

Preferred Skills

• Experience with React, Angular, or Vue.js.
• Experience with Node.js, Django, Flask, Laravel, or similar frameworks.
• Knowledge of cloud platforms such as AWS, Azure, or Google Cloud.
• Familiarity with AI/ML integration or automation is a plus.

Qualifications

• B.Tech/B.E., BCA, MCA, or a related degree.
• Freshers with strong programming skills are welcome to apply.

What We Offer

• Opportunity to work on real-world software projects.
• Learning and professional development opportunities.
• Collaborative and growth-oriented work environment.
• Exposure to modern technologies and development practices.
• Competitive salary based on skills and experience.

We are seeking a highly skilled Full-stack Developer to join our dynamic 

team as a Delivery Module Lead. The ideal candidate will possess strong expertise in Python 

and front-end technologies, enabling them to design, develop, and maintain robust web 

applications. This role requires a proactive individual who can collaborate effectively with 

cross-functional teams to deliver high-quality software solutions that meet business needs. 

Responsibilities: 

∙Design, develop, and maintain scalable web applications using Python and front-end 

technologies. 

∙Collaborate with product managers, designers, and other developers to define project 

requirements and deliver solutions that meet user needs. 

∙Implement responsive user interfaces and ensure optimal performance across various 

devices and browsers. 

∙Write clean, maintainable, and efficient code while adhering to best practices and 

coding standards. 

∙Conduct code reviews and provide constructive feedback to team members to enhance 

code quality. 

∙Debug and troubleshoot issues in existing applications, providing timely resolutions. 

∙Stay updated with emerging technologies and industry trends to continuously improve 

development processes. 

∙Participate in Agile development processes, including sprint planning, daily stand-

ups, and retrospectives. 

Mandatory Skills: 

∙Proficient in Python programming language. 

∙Strong knowledge of front-end technologies such as HTML, CSS, and JavaScript. 

∙Experience with front-end frameworks like React, Angular, or Vue.js. 

∙Familiarity with back-end frameworks such as Django or Flask. 

∙Understanding of RESTful APIs and web services. 

∙Experience with version control systems, preferably Git. 

∙Strong problem-solving skills and attention to detail. 

Full-Stack Engineer (Backend Heavy)

Experience: 4–6 Years | Function: Engineering — Product | Location: On-site

About Us

We’re building the next generation of AI-powered business software, and we’re looking for people who want to shape that future with us. With Lumen, we’re reimagining how users interact with CRM — moving beyond screens, menus and dashboards to an intelligent interface where users can simply ask AI to take actions, retrieve knowledge, generate insights and get work done. With Agent Studio, we’re enabling businesses to build, test and deploy their own AI agents for real-world workflows. And with Invorto, we’re bringing AI to voice, allowing businesses to create intelligent voice agents tailored to their customer and operational use cases.

What makes this especially exciting is the stage and scale of the opportunity. You’ll get to work on genuinely hard problems across LLMs, agents, reasoning, orchestration, voice AI, evaluation, reliability and enterprise security — not as isolated experiments, but as products used in real business workflows. You’ll have the opportunity to build zero-to-one, own meaningful parts of the product end-to-end, work closely with customers, experiment rapidly, and see your work reach production at scale.

Why join now? Because the playbook for enterprise AI is still being written. You won’t just be implementing someone else’s roadmap — you’ll help define the product, architecture and experiences that become that playbook. Expect high ownership, fast iteration, hard technical and product problems, direct customer impact, and the chance to build AI systems that have to work reliably in the real world — not just in a demo.

About the Role

We are looking for a Full-Stack Engineer with a strong backend bias to help build end-to-end product experiences across Lumen and Agent Studio. You will own features from database and API design through to the front-end experience, working closely with product and design to ship AI-powered experiences that real business users depend on every day.

What You’ll Do

Design and build backend services and APIs in Python that power core product and AI-agent features.

Build front-end interfaces and experiences that let users interact naturally with AI agents, insights and CRM workflows.

Own features end-to-end — from data modeling and backend logic to UI implementation, testing and release.

Work with product managers and designers to translate requirements into well-architected, scalable systems.

Integrate with LLM-based and agentic backend systems built by the AI/ML engineering team.

Optimize application performance, reliability and code quality across the stack.

Engage directly with customers and customer success teams to understand workflows, triage issues and inform roadmap decisions.

What We’re Looking For

4–6 years of professional full-stack engineering experience, with a clear backend-heavy skill set in Python.

Strong experience designing and building REST/GraphQL APIs, data models and scalable backend services.

Working proficiency with modern front-end frameworks (e.g., React) to build and integrate user-facing features.

Experience with relational/NoSQL databases, caching and cloud infrastructure.

Ability to move fast in a zero-to-one environment while maintaining code quality and system reliability.

Strong communication skills — this is a customer-facing role, and you will be expected to clearly articulate technical concepts, decisions and trade-offs to both technical and non-technical stakeholders, including customers.

Good to Have

Experience building features on top of LLM or AI-agent backends.

Prior experience in CRM, SaaS or enterprise business applications.

Exposure to real-time or voice-based product interfaces.

Backend Developers

• Contract To Hire (Initial Engagement: 6 months)

Experience: 5+ years

Mandatory Skills:

● Node.js

● Python

● MongoDB

● PostgreSQL

● REST API design and development

● Backend architecture and service design

● Database design, indexing and query optimisation

● Performance tuning

● Authentication/authorisation

● Third-party integrations

● Asynchronous processing and background jobs

● Logging, monitoring and debugging

● Git and collaborative development

● Scalable, maintainable and testable backend services

● Architecture discussions, code reviews, debugging and production support

Good to have:

● Microservices

● Docker

● Cloud platforms

● Redis

● Message queues

● CI/CD

● Observability

Key Responsibilities

● Lead the architecture, design, development, and delivery of scalable backend services

using Python.

● Own technical direction and architectural decisions for backend systems and services.

● Design and build robust RESTful APIs, microservices, and distributed systems

capable of handling high-scale workloads.

● Design and implement real-time communication systems, including WebSocket-based

services, where required.

● Drive system performance, scalability, reliability, availability, and security.

● Lead performance optimization, capacity planning, monitoring, debugging, and

production issue resolution.

● Establish and promote best practices around code quality, testing, observability, CI/CD,

and production readiness.

● Collaborate closely with frontend, product, DevOps, infrastructure, and other

cross-functional teams to deliver end-to-end solutions.

● Mentor and provide technical guidance to engineers, contributing to overall team growth

and engineering excellence.

● Review code and architecture designs, identify technical risks, and drive improvements

across backend systems.

● Take ownership of complex technical problems and deliver reliable, maintainable,

production-grade solutions.

Required Skills & Qualifications

● 5+ years of software engineering experience, with significant experience in backend

development.

● Strong expertise in Python and experience building production-grade backend

applications.

● Proven experience designing and developing REST APIs and microservices

architectures.

● Strong understanding of distributed systems, scalability, fault tolerance, and

high-availability architectures.

● Hands-on experience with WebSockets and real-time backend integrations.

● Strong experience with SQL/NoSQL databases, caching systems, and data-intensive

applications.

● Experience with performance optimization, monitoring, logging, debugging, and

production operations.

● Strong understanding of software engineering principles, design patterns, and clean

architecture.

● Proven ability to lead technical initiatives and make sound architectural decisions.

● Strong communication, collaboration, and technical leadership skills.

● Experience mentoring engineers and conducting effective code and design reviews.

We are seeking talented software developers who are passionate about coding and building & scaling

products. If you love taking on new challenges and have a problem solving mindset to solve problems through

code, you will be a perfect fit for our rockstar engineering team.

Roles and Responsibilities:

● Design and develop backend architectures to support robust, scalable, and secure web applications and

systems with a focus on backend development using Django.

● Design, implement and maintain high quality RESTful APIs to support seamless communication between

frontend, backend and other services.

● Design, implement, and maintain database schemas. Ensure the integrity, performance, and security of

data.

● Ensure the scalability and reliability of our backend infrastructure on AWS. Ensure reliable management of

infrastructure on cloud aiming for 0 downtime of systems.

● Write clean, maintainable, and efficient code, while adhering to best practices and industry standards.

Develop and maintain documentation for our backend systems, APIs, and data models.

● Conduct high quality code reviews and provide feedback to other team members to ensure best practices

are adhered to.

● Take ownership of the development, testing, and deployment of web applications. Break down high-level

business problems into smaller chunks and build systems.

● Work closely with the frontend development team, product managers, and designers to plan new features

and optimize existing ones.

● Constantly aim to improve performance and optimize systems by identifying bottlenecks and resolving

them for increased efficiency.

● Stay up-to-date with the latest technologies such as LLMs, and implement them as and when required

Skills and Qualifications:

● Bachelor's degree in Computer Science, Computer Engineering or a related field.

● 4+ years of experience in full-stack web development, with a focus on backend development.

● Strong proficiency in Python and Django, including experience with Django Rest Framework.

● Experience working with SQL/PostgreSQL databases, including schema design, querying, and

optimization.

● Proficiency in AWS services such as EC2, RDS, S3, and Lambda.

● Familiarity of integrations with third party services and open source frameworks

● Strong understanding of data structures, algorithms, and software design patterns.

● Experience with containerization and orchestration technologies such as Docker and Kubernetes is a plus.

● Familiarity with LLM frameworks such as Langchain, OpenAI, Anthropic, LLaMa is a plus.

● Strong problem-solving skills and ability to work in a fast-paced environment.

● Excellent communication and collaboration skills.

Mandatory (Experience 1) – Must have 3+ years of experience in Full Stack Development with hands-on experience building and deploying production-grade web applications.

2

Mandatory (Skills 1) – Must have strong hands-on experience in Python or Node.js for backend development.

3

Mandatory (Skills 2) – Must have experience developing REST APIs using frameworks such as FastAPI, Flask, Express.js or similar.

4

Mandatory (Skills 3) – Must have hands-on experience with at least one modern frontend framework such as React.js or Angular, along with JavaScript/TypeScript.

5

Mandatory (Skills 4) – Must have hands-on experience with SQL databases such as PostgreSQL, MySQL or similar.

6

Mandatory (Skills 5) – Must have experience integrating frontend applications with backend APIs and third-party services.

7

Mandatory (Skills 6) – Must have good understanding of OOP, data structures, software engineering practices and clean/testable code.

8

Mandatory (Skills 7) – Must have experience with Git/GitHub and standard development practices including code reviews and version control.

9

Mandatory (Skills 8) – Must have experience with cloud platforms such as Azure or AWS and exposure to application deployment.

10

Mandatory (Skills 9) – Must have hands-on experience with Docker/containerized applications and understanding of scalable application development.

11

Preferred (Experience 1) – Experience with Kubernetes, CI/CD pipelines and cloud-native deployments.

12

Preferred (Experience 2) – Experience with Redis/caching, asynchronous programming, microservices or distributed systems.

13

Preferred (Experience 3) – Exposure to AI/ML, Generative AI, LLM applications or RAG-based applications.

14

Mandatory (Age) - Candidate's Age should be below 28

15

Mandatory ( Location ) - Candidates Only From Pune & Mumbai.

16

Mandatory (Education) - Must be a B.E / B.Tech from Tier 1 Colleges (IIT, NIT, IIIT, BITS, DTU, NSUT)