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TransCore (TRN), a subsidiary of ST Engineering, is seeking a talented Sr Software Engineer, Smart Mobility to join our team.  

Summary – About the Role
TransCore is building Smart Mobility, a cloud-native mobility platform that lets people move through tolling, parking, and transit from their phone, and connects the agencies, partners, and consumer apps behind it. We are looking for a Senior Software Engineer to build backend services, APIs, and web experiences that make that platform work.

This is a hands-on senior individual contributor role on a small, fast-moving team. You will design and build cloud-native services on Azure in C# and .NET, work across the stack from message-driven backend processing to the customer and operator web portals, and own your features from design through production. The platform is new, so the patterns you set are the ones the team will build on.

Reporting & Organizational Context

This role reports to the Director of Software Engineering, Smart Mobility, and works closely with the Smart Mobility Architecture function, which owns target-state design and standards. You implement within those standards and feed real implementation experience back into them.

You will work daily with mobile, integration, QA automation, and DevOps engineers, and with the Product Manager who owns the roadmap. Senior engineers here are expected to mentor, review code, and raise the engineering bar, not just close tickets.

Location and Work arrangement

This position will be based in one of these locations – Atlanta, GA, Washington DC, Nashville, TN or Harrisburg, PA. Will consider remote applicants for the right skillset. Position may be hybrid, with a blend of in-office and remote work. Occasional travel may be required based on business needs. Relocation is available for the right candidate.

Essential Duties and Responsibilities

Include the following. Other duties may be assigned.

Design and Build:

• Service development: Design, build, test, and operate scalable backend services and APIs in C# and .NET, including asynchronous and multi-threaded processing of high-volume transaction data.
• Cloud-native patterns: Build services that run as containers on Azure, scale horizontally, degrade gracefully, and handle retries, idempotency, and backpressure correctly.
• Event-driven processing: Implement message-driven and event-driven workflows using queues and streaming technologies such as Azure Service Bus, Event Hubs, Kafka, or RabbitMQ.
• Integrations: Build and maintain integrations to internal tolling and account-management systems, payment providers, and partner APIs against published interface contracts.
• Authentication and API standards: Implement authentication and authorization to standard, using OAuth 2.0 and OpenID Connect for user and service flows, JWT validation, scopes and claims, TLS and mTLS for service-to-service calls, and no hand-rolled auth.
• Data layer: Design schemas, write and tune queries, and own data access and migrations across relational and NoSQL stores.
• Full stack contribution: Contribute to Angular and TypeScript front ends for customer and operator web applications as product needs require.

Quality and Operations:

• Testing: Write unit and integration tests as part of the definition of done, and partner with QA Automation on coverage for the features you build.
• Production ownership: Own your services in production, respond to issues in the code you own, and take part in on-call rotation and root cause analysis as the team matures.
• Instrumentation and telemetry: Instrument services with OpenTelemetry traces, metrics, and logs against the platform standard, and use Dynatrace and the Grafana stack to answer what a service is actually doing in production.
• Secure by default: Build to security and PCI-DSS expectations, including safe handling of payment and personal data, secrets management, and secure API design.
• Performance: Profile and tune services against throughput and latency targets, and identify scaling limits before they reach production.

Collaboration and Technical Leadership:

• Design participation: Take part in design reviews and technical decisions, document what you build, and make the tradeoffs explicit.
• Code review and mentoring: Review peer code, mentor less experienced engineers, and help set the coding standards and patterns for a new codebase.
• Agile delivery: Work in sprints, give realistic estimates, and surface risk early rather than late.

Requirements and Qualifications
To perform this job successfully, an individual must be able to perform each essential duty satisfactorily. The requirements listed below represent the knowledge, skill, and/or ability required.

• Bachelor’s degree in Computer Science, Engineering, or a related field, or equivalent practical experience.
• 10 to 13 years of professional software development experience, with recent hands-on work building production services.
• Strong C# and .NET experience, including .NET Core or later, ASP.NET Core Web API, and asynchronous or multi-threaded programming.
• Demonstrated experience designing and operating cloud-native applications on Azure, AWS, or GCP, with Azure preferred.
• Practical experience with message queues or event streaming, and with the failure modes of distributed systems.
• Working knowledge of authentication and API security standards, including OAuth 2.0, OpenID Connect, JWT, TLS and mTLS, and safe handling of tokens, keys, and secrets in application code.
• Experience designing systems that scale, including caching, partitioning, load distribution, and performance tuning.
• Strong database skills, including schema design and query tuning in SQL Server or PostgreSQL.
• Experience with containers and Docker, and comfort working in a CI/CD environment with Git-based source control.
• Experience instrumenting applications for observability, ideally with OpenTelemetry, and using an APM or dashboarding platform such as Dynatrace, Grafana, or Application Insights to diagnose real production problems.
• Strong debugging, analytical, and written communication skills.

Preferred Qualifications

• Front-end development experience with Angular and TypeScript, including HTML5, CSS3, and modern single-page application patterns. This is a meaningful plus as the platform adds customer and operator web functionality.
• Working knowledge of Python or Go as a secondary language.
• Experience integrating with an identity provider such as Microsoft Entra ID, Auth0, or Okta, including SAML, SCIM, or agency and enterprise single sign-on.
• Experience with OpenAPI-first API design, versioning, and contract testing.
• Experience with Kubernetes or Azure Kubernetes Service.
• Experience with NoSQL or document stores such as Cosmos DB, and with caching layers such as Redis.
• Experience with payments, digital wallets, or high-security transaction processing, including PCI-DSS environments.
• Experience with systems that interface with IoT devices, BLE beacons, roadside hardware, or telematics, and with high-volume real-time data ingestion.
• Background in mobility, transportation, tolling, parking, or logistics technology.
• Experience using approved AI-assisted engineering tools responsibly to accelerate development and troubleshooting.

Physical Demands/Work Environment
While performing the duties of this job, the employee is regularly required to talk or hear. The employee is frequently required to sit. The employee is occasionally required to stand, walk; use hands to finger, handle, or feel and reach with hands and arms. The employee must occasionally lift and/or move up to 10 pounds. While performing the duties of this job, the employee is occasionally exposed to fumes or airborne particles; outside weather conditions and moving traffic. The noise level in the work environment is usually moderate.

* TransCore complies with federal and state disability laws and provides reasonable accommodation for employees with disabilities. 

Equal Opportunity Employer / Protected Veterans / Individuals with Disabilities

This employer is required to notify all applicants of their rights pursuant to federal employment laws. For further information, please review the Know Your Rights notice from the Department of Labor.