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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.

- Degree in Computer Science (BS/MS), related technical field or equivalent practical experience
- 8+ years of industry experience in product development
- Experience in coaching and mentoring team members
- Must own a specific component of the product. Gathering requirements by working with product management. Working closely with development managers in defining external product interfaces
- Must have excellent written and verbal communication skills. Must articulate various design approaches and design decisions clearly - within the team and across the teams.
- Must work with QA engineers to devise proper test constructs - unit testing and integration tests.
● Leads a project end-to-end and collaborates across functions. Drives planning,
estimation and execution.
● Understands requirements well and comes up with efficient design
● Develops complex, well backed and bug-free products. Estimates accurately.
● Takes well-reasoned tech decisions keeping in mind goals and trade-offs
● Becomes a go-to person in more than one area. Provide technical mentoring to team
● Communicates clearly, gets clarifications and establishes expectations for all parties
● Helps establish SDLC best practices and high standards of code quality
● Demonstrates excellent problem solving & debugging skills
● Proactively identifies and resolves issues in requirements, design and code
● Contributes in tech recruitment efforts
Ideal Candidate Profile
● Solid experience in RoR, Golang, NodeJS or Python. Good to have exposure to ML.
● Should have experience in cloud computing
● Has an ability to quickly learn and contribute in multiple codebase
● Overcomes roadblocks and requires minimal oversight
● Takes initiatives to fix issues/tech debts before assigned to him/her
● Able to deep dive into codebase and advise QA of possible regression impact
● Communicates tech decisions through design docs and tech talks
● Has delivered projects with end-to-end accountability
● Keeps track of industry trends and introduces right tech/tools for a given job
● Excellent understanding of software engineering practices, Design Patterns, Data
Structures, Algorithms
● 8+ years of experience in product driven organization
● A Bachelors or Masters degree in engineering from a reputed institute (preferably
IITs, NITs, or other top engineering institutes)
- Strong proficiency with JavaScript
- Knowledge of Node.js and frameworks available for it
- A good understanding of the nature of asynchronous programming, its challenges, and workarounds
- Good understanding of server-side templating languages
- Good understanding of server-side CSS preprocessors
- Basic understanding of front-end technologies, such as HTML5, and CSS3
- Understanding of accessibility and security compliance
- Experience in user authentication and authorization between multiple systems, servers, and environments
- Proficiency in API integrations
- Understanding of fundamental design and architecture principles to scale an application
- Understanding differences between multiple delivery platforms, such as mobile vs. desktop, and optimizing output to match the specific platform
- Creating database schemas that represent and support business processes
- Implementing automated testing platforms and unit tests
- Proficient understanding of code versioning tools, such as Git
- A degree in any discipline
- Good communication and team skills
- Ability to listen to the requirements of team members and clients and translate them into great solutions
Mandatory Skills :
Front end : Angular, HTML5, CSS3, JavaScript
Backend : Python
Framework : Django python web framework
Any experience of working with NLP, computer vision and deep learning will be additional plus point
- Knowledge of MySQL necessary
- Basic HTML & Javascript
- No framework experience needed (will be trained on Laravel)
- Strong programming fundamentals essential
- Should be living on the western line of Mumbai (Andheri to Borivali ideal) - Central do not apply
- Work Timings: 10:00 to 7:00 pm with 2nd & 4th Saturday off
- Should be comfortable working in a small team on product development environment
- Callify.ai SaaS Voice based software product








