Pre- Sales Solutions Architect

Review Criteria

• Strong Senior Backend Engineer profiles
• Must have 5+ years of hands-on Backend Engineering experience building scalable, production-grade systems
• Must have strong backend development experience using one or more frameworks (FastAPI / Django (Python), Spring (Java), Express (Node.js).
• Must have deep understanding of relevant libraries, tools, and best practices within the chosen backend framework
• Must have strong experience with databases, including SQL and NoSQL, along with efficient data modeling and performance optimization
• Must have experience designing, building, and maintaining APIs, services, and backend systems, including system design and clean code practices
• Experience with financial systems, billing platforms, or fintech applications is highly preferred (fintech background is a strong plus)
• (Company) – Must have worked in product companies / startups, preferably Series A to Series D
• (Education) – Candidates from top engineering institutes (IITs, BITS, or equivalent Tier-1 colleges) are preferred

Role & Responsibilities

As a Founding Engineer at company, you'll join our 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 perfect for someone who thrives in a dynamic startup environment where requirements evolve quickly and problems need 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 company’s billing automation and revenue recognition capabilities
• Work across the full stack: Contribute to both backend services and frontend interfaces, ensuring seamless user experiences
• Implement critical integrations: Connect company with external systems including CRMs, data warehouses, ERPs, and payment processors
• Optimize for scale: Build systems that handle complex pricing models, high-volume usage data, and real-time financial calculations
• Drive quality and best practices: Write clean, maintainable code while participating in code reviews and architectural discussions
• Solve complex problems: Debug issues across the stack and work closely with teams to address evolving client needs

The Impact You'll Make-

• Power business growth: Your code will directly enable billing and revenue operations for fast-growing B2B companies, helping them scale without operational bottlenecks
• Build critical financial infrastructure: Contribute to systems handling millions in transactions while ensuring accurate, compliant revenue recognition
• Shape product direction: Join during our scaling phase where your contributions immediately impact product evolution and customer success
• Accelerate your expertise: Gain deep knowledge in financial systems, B2B SaaS operations, and enterprise software while working with industry veterans
• Drive the future of B2B commerce: Help create infrastructure powering next-generation pricing models from usage-based to value-based billing.

• Strong understanding of Core Python, data structures, OOPs, exception handling, and logical problem-solving.
• Experience in at least one Python framework (FastAPI preferred, Flask/Django acceptable).
• Good knowledge of REST API development and API authentication (JWT/OAuth).
• Experience with SQL databases (MySQL/PostgreSQL) & NoSQL databases (MongoDB/Firestore).
• Basic understanding of cloud platforms (GCP or AWS).
• Experience with Git, branching strategies, and code reviews.
• Solid understanding of performance optimization and writing clean, efficient code.
• Develop, test, and maintain high-quality Python applications using FastAPI (or Flask/Django).
• Design and implement RESTful APIs with strong understanding of request/response cycles, data validation, and authentication.
• Work with SQL (MySQL/PostgreSQL) and NoSQL (MongoDB/Firestore) databases, including schema design and query optimization.
• Experience with Google Cloud (BigQuery, Dataflow, Notebooks) will be a strong plus.
• Work with cloud environments (GCP/AWS) for deployments, storage, logging, etc.
• Use version control tools such as Git/BitBucket for collaborative development.
• Support and build data pipelines using Dataflow/Beam and BigQuery if required.
• Experience with GCP services like BigQuery, Dataflow (Apache Beam), Cloud Functions, Notebooks etc
• Good to have Exposure to microservices architecture.
• Familiarity with Redis, Elasticsearch, or message queues (Pub/Sub, RabbitMQ, Kafka).
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Python Backend Developer (5+ years experience)

We are seeking an experienced Python Backend Developer with at least 5 years of hands-on experience in Python and Django development. The ideal candidate will have a strong background in MySQL and MongoDB databases, as well as knowledge of HTML, CSS, JavaScript frameworks, and cloud technologies like AWS, Azure or Google Cloud.Key Responsibilities:

• Design and develop scalable, high-performance Python applications using the Django framework
• Write clean, maintainable, and well-documented code
• Optimize database queries and schema design for improved performance
• Integrate applications with various APIs and third-party services
• Collaborate with cross-functional teams to gather requirements and deliver solutions
• Participate in code reviews, testing, and deployment processes
• Continuously learn and stay updated with the latest technologies and best practices

Required Skills and Experience:

• Bachelor's or Master's degree in Computer Science, Information Technology or a related field
• 5+ years of professional experience in Python and Django development
• Proficient in MySQL and MongoDB databases, with the ability to write complex queries and optimize database performance
• Hands-on experience with HTML, CSS, and at least one JavaScript framework (e.g., React, Angular, Vue.js)
• Knowledge of cloud technologies like AWS, Azure, or Google Cloud is preferred
• Strong problem-solving and algorithmic skills
• Excellent communication and teamwork skills
• Passion for continuous learning and innovation

Preferred Qualifications:

• Experience in developing and deploying applications on cloud platforms
• Knowledge of containerization technologies like Docker and Kubernetes added advantages

1. Proficiency in Python 3.x based web and backend development

2. Solid understanding of Python concepts

3. Experience with some form of Machine Learning (ML)

4. Experience in using libraries such as Numpy and Pandas

5. Some form of experience with NLP and Deep Learning using any of Pytorch, Tensorflow, Keras, Scikit-learn or similar

6. Hands on experience with RDBMS such as Postgres or MySQL

7. Experience building REST APIs using DRF or Flask

8. Comfort with Git repositories, branching and deployment using Git

9. Working experience with Docker

10. Basic working knowledge of ReactJs

11. Experience in deploying Django applications to AWS,Digital Ocean or Heroku

Responsibilities and Duties:

• Expert in Python, with knowledge of Python web framework - Django
• Familiarity with backend automated testing tools and frameworks
• Experience with backend/API development
• Architect, develop and maintain backend libraries/codebase, database & server.
• Develop object-oriented software, with mastery of one or more relevant languages (Django).
• Evaluate competitive and innovative products and design approaches to identify best practices and encourage innovation.
• Understanding the requirement of a client, document the scope and chart out a plan of implementing the scope
• Work with design team to give inputs related to the wire-frames and then the design along with incorporating Client Feedback
• Explore the difference between B2B and B2C projects before implementing the code
• Work in teams of 2-3 on various projects as per the requirement using git as version control
• Having good knowledge of APIs creation and database architecture
• Good Grasp in respective technology (Django)
• Documenting the process and main functions along the developing process
• Design and develop highly scalable, highly available, reliable, secure, and fault-tolerant systems with minimal guidance for one of the fastest-growing companies in India.

Required Experience, Skills and Qualifications:

• 3-5 years of experience required
• Strong hand on Django-Python
• Excellent knowledge of using the Git version control system and deployment via Git.
• You have creative visualization, critical thinking, deductive & pragmatic reasoning and can think out-of-the-box
• Ability to quickly adapt & independently work in a fast-paced Agile environment with minimum supervision.
• A self-starter with demonstrated ability to take initiative, who can proactively identify issues/opportunities and recommend action.

Roles:

• Developing core infrastructure in Python, Django.
• Developing models and business logic (e. g. transactions, payments, diet plan, search, etc).
• Architecting servers and services that enable new product features.
• Building out newly enabled product features

• Minimum 4 years of industry or open-source experience.
• Proficient in at least one OO language: Python(preferred)/Golang/Java.
• Writing high-performance, reliable and maintainable code.
• Good knowledge of database structures, theories, principles, and practices.
• Experience working with AWS components [EC2, S3, RDS, SQS, ECS, Lambda].

About us:

HappyFox is a software-as-a-service (SaaS) support platform. We offer an enterprise-grade help desk ticketing system and intuitively designed live chat software.

We serve over 12,000 companies in 70+ countries. HappyFox is used by companies that span across education, media, e-commerce, retail, information technology, manufacturing, non-profit, government and many other verticals that have an internal or external support function.

To know more, Visit! https://www.happyfox.com/

We’re looking for a Senior Backend Engineer to join our engineering team to help build and maintain our growing list of products. You should have prior experience being responsible for building sufficiently complex features by yourself.

Responsibilities: 

• Implement product features by writing clean, robust, reusable code with tests
• Conduct peer reviews to keep the codebase a great environment to work on
• Collaborate with Product Managers, Designers and Engineers to deliver high-quality features
• Bring new ideas and best practices to improve the team and the codebase

Requirements:

• 5+ years of professional work experience
• Proficiency in backend programming languages like Python
• Experience working with web application frameworks like Django
• Experience in building web services using relational databases like PostgreSQL or NoSQL databases like MongoDB
• Proficiency in writing highly performant and scalable code
• Experience in building REST APIs and a good understanding of best practices around building APIs
• Good communication skills with an ability to articulate your views
• Excellent analytical and problem-solving skills