Software Engineer, Payments (.NET / Vue.js)

Neumo; Bloomington (IN); On-site; USD 90,000 - 120,000; Full time

Job summary

Neumo, based in Bloomington, IN, is seeking a Software Engineer to design, build, test, and maintain features for our payments platform including merchant portal and checkout experiences.

The role spans the stack (.NET 8, Vue.js, Azure Table/Blob Storage) to deliver reliable, secure software that moves money. 3+ years of experience in transaction-processing or high-reliability systems preferred.

Qualifications

• Experience building web apps and REST APIs with .NET 8.
• Proficient in Vue.js and modern front-end development.
• Familiar with PCI DSS secure software practices and payments domain is a plus.

Responsibilities

• Translate business requirements into designs and working software.
• Develop and maintain backend services and APIs using C# and .NET 8.
• Build front-end features in Vue.js for merchant portal and checkout.
• Design data models for Azure Table Storage and Blob Storage.
• Integrate with payment processors and terminals.
• Write tests and participate in code reviews and CI/CD.

Skills

C#

.NET 8

Vue.js

REST APIs

Azure

CI/CD

Testing

Git/GitHub Actions

Agile/Scrum

Security/PCI DSS

Education

Bachelor’s degree in Computer Science or related field

Tools

Azure DevOps

Azure Storage (Table/Blob)

GitHub Actions

ASP.NET Core

Job description

Job Summary

The individual in this role will design, build, test, and maintain features for our payments platform, including the web-based merchant portal and checkout experiences, backend services and APIs, and integrations with physical payment terminals and payment processors. The Software Engineer works across the stack (.NET 8, Vue.js, and Azure Table and Blob Storage) to deliver reliable, secure, and well-tested software that accurately moves money. Competitive candidates have [3+] years of professional software development experience, ideally on transaction-processing or other high-reliability systems.

Job Summary

The individual in this role will design, build, test, and maintain features for our payments platform, including the web-based merchant portal and checkout experiences, backend services and APIs, and integrations with physical payment terminals and payment processors. The Software Engineer works across the stack (.NET 8, Vue.js, and Azure Table and Blob Storage) to deliver reliable, secure, and well-tested software that accurately moves money. Competitive candidates have [3+] years of professional software development experience, ideally on transaction-processing or other high-reliability systems.

Duties And Responsibilities

• Translate business requirements and payment processes (authorization, capture, void, refund, settlement, reconciliation) into technical designs and working software.
• Design, develop, and maintain backend services and APIs using C# and .NET 8, including payment, webhook, and reporting endpoints.
• Build and maintain front-end features in Vue.js for the merchant portal, hosted checkout, and admin tools, with attention to usability, accessibility, and cross-browser behavior.
• Design and implement data models and access patterns in Azure Table Storage and Blob Storage, including partition and row key design, query performance, and data retention.
• Build integrations with payment processors, gateways, and terminal software, handling asynchronous responses, timeouts, retries, and error conditions gracefully.
• Design for idempotency, data consistency, and fault tolerance so that duplicate requests, network failures, and partial failures never result in incorrect charges or lost transactions.
• Support terminal-related development, including communication between terminals and the platform, offline or store-and-forward scenarios, and firmware and application update workflows.
• Write clean, maintainable, and well-documented code, and participate in code reviews, design discussions, and architecture decisions.
• Write unit, integration, and automated tests, and partner with QA to ensure features are testable and thoroughly validated before release.
• Investigate and resolve defects, including issues escalated by the support engineering team, using logs, monitoring, and transaction data to identify root causes.
• Collaborate with the support engineering team to improve diagnostics, logging, and internal tooling so that transaction lookups and issue investigations are faster and more reliable.
• Follow secure coding practices and PCI DSS requirements, including protection of cardholder data, encryption, tokenization, secrets management, and access controls.
• Support certification and compliance efforts, such as card brand, EMV, acquirer/processor, and PCI-related requirements.
• Contribute to CI/CD pipelines, deployments and release readiness, and support post-release monitoring.
• Monitor application performance and reliability, and improve performance, scalability, and cost efficiency in Azure.
• Identify technical debt and recurring problem areas and recommend and implement improvements.
• Independently own a workstream or product area (for example, terminal integration, merchant portal, or payment APIs), from design through deployment and ongoing support.
• Participate in daily engineering meetings to update teammates and management on status.
• Present technical expertise in training, implementation, and cross-team environments as needed.
• Perform other duties as assigned.

Education And Experience

• [3-6] years of professional software development experience, including:
  • Building and maintaining web applications and REST APIs
  • Working within Agile or Scrum teams, including code reviews and version control workflows
  • Writing automated unit and integration tests
• Proficiency in C# and .NET (.NET 8 preferred), including ASP.NET Core web APIs
• Experience with a modern JavaScript front-end framework, preferably Vue.js, along with HTML, CSS, and TypeScript or JavaScript
• Experience with cloud-based or NoSQL data storage, such as Azure Table Storage, Blob Storage, or similar
• Experience with Git-based source control and CI/CD pipelines (e.g., Azure DevOps or GitHub Actions)
• Preferred: experience in payments, fintech, or financial services
• Preferred: experience with the Microsoft Azure ecosystem, including Azure Functions, Service Bus or Queue Storage, Key Vault, Application Insights, and Log Analytics
• Preferred: knowledge of PCI DSS and secure software development practices