Job Overview

WEX is hiring a Senior Back End Engineer for its Mobility Engineering organization in Bangalore, India. This is a full-time opportunity within the Product Development and Engineering function. The role is part of the NAM Experiences team, which supports fleet management and mobility payment solutions delivered through SaaS products and APIs.

The position is designed for an experienced backend engineer who can build reliable services for large-scale business applications. You will work on systems that support fleet companies and their employees, including configurable payment and spending controls. The role combines hands-on Java backend development with API engineering, cloud infrastructure, automated testing, system design, production support, and technical mentoring.

Key Responsibilities

• Design and develop scalable, secure, highly available backend services for business-critical applications.
• Build public REST APIs using Java and internal gRPC APIs for communication between services and systems.
• Contribute to system architecture, technical designs, and important engineering decisions.
• Work with senior engineers to evaluate design options and maintain alignment across technical teams.
• Develop automated unit, integration, end-to-end, concurrency, load, and performance tests.
• Analyze existing applications to identify scalability limitations, technical debt, performance bottlenecks, and reliability concerns.
• Improve application automation for testing, monitoring, healing, scaling, continuous integration, and continuous deployment.
• Partner with product managers, designers, and engineers to deliver new product capabilities.
• Review code, provide constructive feedback, and help maintain engineering standards.
• Mentor junior and mid-level engineers through technical guidance and knowledge sharing.
• Investigate complex production issues, determine root causes, implement fixes, and document corrective actions.
• Compare competing technologies and provide technical recommendations based on their strengths and limitations.
• Maintain design documentation, runbooks, change management documents, and readiness plans.
• Support production systems by monitoring applications, responding to incidents, and driving improvements in reliability and performance.

Required Skills

Candidates should have strong backend software engineering experience and a solid understanding of data structures, algorithms, object-oriented design, and practical problem solving. The role requires the ability to design internet-scale services with attention to scalability, availability, security, and reliability.

Strong professional experience with Java, Go, or C# is required, with Java being particularly relevant to the position. Experience with Spring Boot and backend application frameworks is important. Candidates should be comfortable developing and optimizing RESTful APIs and working with SQL and MongoDB-based data solutions.

The position also requires experience with AWS as a foundational cloud environment, including core cloud services, deployment approaches, observability, and monitoring. Experience working with production applications and solving complex reliability issues is highly relevant.

Required Technologies

• Java
• Spring Boot
• Go
• C#
• REST APIs
• gRPC
• OData
• SQL
• MongoDB
• AWS
• Kafka
• Docker
• Kubernetes
• Git
• CI/CD
• Cloud-native architecture
• Event-driven architecture
• API security
• PCI DSS

Preferred Skills

Experience with event-driven systems and Apache Kafka is preferred. Candidates with previous exposure to payment solutions can bring useful domain knowledge to the role. Familiarity with Docker and Kubernetes is valuable for developing and operating cloud-native services.

Experience with API security and PCI DSS compliance is also beneficial, particularly for professionals who have worked on payment or financial technology systems. The ability to work with an established codebase, improve existing implementations, reduce technical debt, and help modernize legacy systems is another valuable capability.

Education

A Bachelor’s degree in Computer Science or Software Engineering is required. A Master’s degree in Computer Science or Software Engineering is preferred.

Experience

The required professional experience is 5 to 8 years in software engineering. The job description also identifies 8+ years as a preferred qualification. Candidates should demonstrate practical experience developing backend services, designing scalable systems, working with APIs, and supporting production software.

Prior experience mentoring junior engineers is expected. Strong knowledge of system scalability, availability, security, reliability, and cloud infrastructure is important for this senior-level position.

Soft Skills

Strong written and verbal communication skills are important because the engineer will work with senior engineers, product managers, designers, and other cross-functional stakeholders. A collaborative and empathetic approach is expected when reviewing designs, discussing technical tradeoffs, and supporting teammates.

The successful candidate should be comfortable taking ownership of complex technical problems, working independently, sharing knowledge, mentoring engineers, and making practical engineering decisions. Analytical thinking and a structured approach to troubleshooting are particularly useful for production and large-scale system challenges.

Benefits of Working in this Role

This role provides the opportunity to work on large-scale mobility and payment technology through backend services, APIs, cloud infrastructure, and distributed application architectures. Engineers can gain exposure to scalable SaaS platforms, event-driven systems, cloud-native technologies, production observability, and payment-related engineering requirements.

The position also offers opportunities to contribute to architecture decisions, guide engineering decisions, mentor other engineers, evaluate technologies, and participate in reliability and continuous improvement initiatives.

Work Mode

This is a full-time role based in the Bangalore office. The supplied job information identifies the position as a Bangalore, India opportunity within Product Development and Engineering.

Location

The job is located in Bangalore, Karnataka, India.

Who Should Apply

This opportunity is suitable for experienced backend engineers, Java developers, Spring Boot developers, API developers, cloud engineers, and software professionals with strong distributed systems experience. It is particularly relevant for candidates who have built scalable services and have practical AWS experience.

Professionals with experience in payments, event-driven architecture, Kafka, Docker, Kubernetes, API security, PCI DSS, SQL, MongoDB, and production support should consider this role. Candidates should be able to demonstrate genuine hands-on engineering experience rather than relying only on theoretical knowledge.

Career Growth

The role can support growth in backend architecture, distributed systems, cloud engineering, API design, production reliability, and technical leadership. Senior engineers will have opportunities to influence system design, guide engineering decisions, mentor other developers, evaluate technologies, and contribute to modernization and continuous improvement initiatives.

Application Advice

Highlight 5 to 8 years of software engineering experience and clearly demonstrate hands-on backend development. Emphasize Java, Spring Boot, REST APIs, gRPC, AWS, SQL, MongoDB, and any relevant distributed systems work. Include measurable examples of scalability improvements, reliability enhancements, performance optimization, automated testing, or production issue resolution where available.

If you have worked with Kafka, Docker, Kubernetes, payment systems, API security, PCI DSS, or cloud-native architectures, mention those experiences clearly. Also highlight mentoring, code reviews, system design, and technical decision-making experience. Keep your resume accurate and ensure that every technology listed reflects genuine professional experience.