Job Description

Pune, Bengaluru
Fulltime##### Role Description & Responsibilities

Backend Development :

o Design, develop, and maintain secure, scalable, and high-performance backend services and APIs for payment systems, financial transactions, and other fintech products.

o Implement payment gateways, fraud detection systems, transaction processing, and other financial services.

o Optimize backend performance to ensure low latency and high throughput in processing payments and handling sensitive financial data. Architecture & Integration :

o Architect backend systems that integrate with third-party payment processors, banks, and financial institutions using APIs, microservices, or event-driven architectures.

o Design and implement secure, efficient, and reliable payment flows, including support for different payment methods (credit cards, ACH, digital wallets, etc.).

o Ability to solution and architect for other systems and business verticals Security & Compliance :

o Implement security best practices for handling sensitive financial data (e.g., encryption, tokenization, PCI DSS compliance).

o Ensure the backend services comply with regulatory standards and industry best practices, including GDPR, PCI-DSS, and other fintech regulations. Testing & Debugging :

o Write unit, integration, and system tests to ensure the reliability, scalability, and security of the backend systems.

o Collaborate with QA engineers to ensure thorough testing and debugging of financial transactions and payment systems. Collaboration :

o Work closely with frontend developers, business analyst, and DevOps engineers to ensure seamless integration between frontend and backend systems.

o Participate in code reviews, knowledge-sharing sessions, and collaborative development to improve team productivity and code quality.

o Willingness to participate in and contribute to customer interactions Documentation :

o Create and maintain clear, concise documentation for backend services, APIs, and integrations.

o Document the system design, architecture decisions, and any payment-related workflows.##### Required Skills, Experience & Qualities

• 8-12 years of experience as a backend developer, with a strong focus on building scalable and secure applications in the Payments or Fintech domain.
• Familiarity with handling payment systems, transaction processing, or integrations with payment gateways like Stripe, PayPal, Visa/Mastercard, ACH, or similar platforms.
• Proficiency in backend programming languages such as Java , Python , Ruby , Node.js and/or Go .
• Strong experience with RESTful API design and microservices architecture.
• Experience with Databases : SQL (PostgreSQL, MySQL) and NoSQL (MongoDB, Cassandra).
• Familiarity with message brokers and queuing systems (e.g., RabbitMQ, Kafka) for event-driven architectures.
• Experience with cloud platforms (AWS, Azure, GCP) and their respective services (e.g., Lambda, DynamoDB, SQS).
• Knowledge of data encryption , tokenization , and secure transaction handling .
• Experience with PCI-DSS compliance and other relevant security standards for financial services.
• Strong problem-solving skills, with the ability to troubleshoot complex issues in a financial environment.
• Experience optimizing systems for high availability, fault tolerance, and performance.
• Proficiency with Git for version control.
• Familiarity with continuous integration/continuous deployment (CI/CD) pipelines and related tools (Jenkins, CircleCI, GitLab CI).
• Familiarity with Agile development processes, and experience working in cross-functional teams using tools like Jira, Confluence, or Trello.
• Understanding of Distributed Systems and Scalable Architectures for handling large volumes of financial transactions.
• Experience with DevOps practices , containerization (Docker), and orchestration tools (Kubernetes).
About Us


Calfus is a Silicon Valley headquartered software engineering and platforms company. The name Calfus finds its roots and ethos in the Olympic motto "Citius, Altius, Fortius - Communiter". Calfus seeks to inspire our team to rise faster, higher, stronger, and work together to build software at speed and scale.


Calfus Inc. is an equal opportunity employer and welcomes candidates from all backgrounds to apply. We encourage applications from individuals with diverse experiences and perspectives, as we believe in the power of a diverse and inclusive workforce to drive innovation and success.