Designs, develops, and supports scalable backend services, REST and gRPC APIs, automated testing, monitoring, and continuous delivery. Leads system architecture and technical initiatives, performs code reviews, mentors engineers, troubleshoots production issues, and documents designs and operational procedures. The role also supports major customer implementations and integrations on the IBM iSeries platform while collaborating with product, engineering, and customer stakeholders.
About the Team/Role
We are seeking a seasoned Sr. Software Engineer in the WEX Mobility Engineering organization. This role will sit in the Mobility team that caters to fleet management and mobility payments solutions for our large customers. Mobility development team spans across USA, Brazil, and India. Our Mobility systems provide SaaS and API solutions to various customers. WEX Mobility products enable credit issuance to fleet companies and their workers in the form of WEX or cobranded credit cards, usable at fueling stations and select other merchants. At WEX, we provide fleet managers and operators with fuel discounts, and flexibility to configure spend controls that restrict fleet members to use their cards at configured merchants, for configured amounts and velocity. This role includes large customer implementation/integration with TMS and support of products on the IBM iSeries platform.
The role encompasses various responsibilities and required skills.
- Technical Expertise — Engineer and implement software solutions tailored for the iSeries environment and possess deep knowledge of iSeries technologies, including RPG III,RPGILE, RPG IV, RPG400, CLP, DDS, C# and all IBM Utilities, SOAP, PHP, .NET web services and DB2 databases, which are crucial for effective development
- Project Leadership — Senior engineers often lead technical initiatives, guiding teams through project lifecycles,
- Mentorship — provide guidance and support to junior developers, fostering skill development and providing guidance on best practices and coding standards.
- System Design — Responsibilities include architecting scalable and efficient systems and technical design documentation.
- Collaboration — Senior engineers work closely with stakeholders, product managers and large customers to gather requirements and translate them into technical solutions, enhancing overall project success to ensure alignment with business goals.
- Quality Assurance — Senior engineers are responsible for code reviews and implementing testing strategies to maintain software quality.
How you’ll make an impact:
- Design, develop, and maintain robust, scalable, and high-performance object oriented code in our backend services.
- Develop public REST APIs using Java and internal gRPC APIs for inter-service and inter-system communication.
- Craft systems designs, lead design decisions, and drive alignment with other senior engineers.
- Write automated unit tests, integration tests, end-to-end tests, concurrency tests, load/performance tests.
- Analyze existing systems to identify bottlenecks, tech debt, and implement scalability, and stability improvements.
- Implement automation for testing, monitoring, healing, and scaling applications, continuous integration and deployment to reduce time to market
- Collaborate with cross-functional teams, including product managers, designers, and other engineers, to define and implement new features.
- Conduct code reviews (comment, approve, seek revisions, merge), mentor junior and mid-level engineers, and actively promote engineering best practices.
- Dive deep and troubleshoot complex issues, devise fixes, author root cause analysis documents, and ensure lasting performance and reliability.
- Conduct objective and comparative analyses of competing technologies to advise the team of pros and cons of a technology solution
- Maintain robust documentation (design docs, run books, change management docs, and readiness plans)
- Provide live-site support for production applications by monitoring systems, ensuring rapid incident resolution, and driving continuous improvement.
- Drive cross-team projects as a single-threaded-owner (STO) or tech lead, and actively unblock other engineers to make progress.
- Support Mobility Major Account Implementations on IBM iSeries platform.
Experience you'll bring:
- Bachelor’s degree in Computer Science or Software Engineering
- 10+ years of professional experience in software engineering.
- Strong understanding of data structures and algorithms, object-oriented design, and problem-solving skills.
- Expertise in designing and developing internet-scale services with scalability, availability, security, and reliability design tenets.
- Excellent written and verbal communication skills, and a collaborative and empathetic mindset.
- Proficiency in backend development, with proficiency expertise in Java or C#, and frameworks like SpringBoot, building and optimizing RESTful APIs, ODATA framework, and SQL
- 10+ years Deep Technical knowledge of iSeries technologies, including RPG III, RPGILE, RPG IV, RPG400, CLP, C++,DDS, all IBM Utilities, SOAP, PHP, .NET, web services and DB2 databases, which are crucial for effective development.
- IBM iSeries communications, administration, SSL, SSH, TCP/IP, web services experience
Preferred Qualifications
- Master’s degree in computer science or software engineering.
- 8 years of experience in software engineering.
- Experience with event-driven architecture and tools like Kafka.
- Experience working on card payments
- Familiarity with cloud-native architecture (containerization using tools such as Docker and Kubernetes).
- Awareness of API security and PCI DSS compliance requirements
- Ability to work on existing codebase, contribute improvements, and adapt to legacy systems’ constraints.
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