Senior Software Engineer/.NET Developer (On-Site)

We build and maintain the systems that government motor vehicle agencies depend on to test, license and certify drivers. Our software runs in production across more than two dozen jurisdictions in the United States and Canada, where reliability and auditability are contractual obligations rather than aspirations.

We are seeking a Senior Software Engineer to design, build and maintain data-intensive enterprise applications across that portfolio. The majority of this work is in C# and .NET , backed by SQL Server . Our front ends vary: some applications are built entirely in Vue.js , one of our primary applications uses Vue selectively, and another uses none at all — so you will move between modern component-based front ends and traditional server-rendered views. Some of our highest-throughput components are written in C++, so working proficiency there — or the appetite to develop it — matters, but .NET is where most of your time will be spent.

Success requires strong problem-solving skills, comfort moving across mixed technology stacks, and genuine ownership of delivering reliable solutions in real production environments. You will work in systems that carry years of accumulated business logic, and you will help modernize them without disrupting the jurisdictions that rely on them daily.

Duties and Responsibilities:

Design, build and support web applications and services using C# and .NET MVC

Design and optimize SQL Server queries and data access patterns for high-performance transactional systems, with emphasis on query efficiency, indexing strategy and minimizing latency

Contribute to front-end development across a mixed estate — Vue.js applications, partial Vue adoption, and traditional server-rendered views

Maintain and extend core application logic in C++ where our highest-throughput components require it

Troubleshoot and resolve complex production issues spanning database, backend and UI layers

Work within and improve complex legacy systems while maintaining production stability

Contribute to ongoing modernization efforts across legacy and current platforms

Deliver jurisdiction-specific change requests and configuration work to committed dates

Collaborate with QA, Product and cross-functional teams to deliver high-quality releases

Participate in code reviews and help raise development standards

Support automated testing and CI/CD pipeline improvements

Mentor engineers and contribute to the technical growth of the team

Education and Experience:

Strong professional experience with C# and .NET, building and maintaining production web applications and services

Strong experience with SQL Server, including query design and optimization, performance tuning and efficient data access patterns

Strong object-oriented design skills, with a working commitment to SOLID principles and the judgment to apply them pragmatically in existing code

Experience with systems where performance and reliability are critical to business operations

Working proficiency in C++, sufficient to read, debug and modify existing production code, with the willingness to deepen it. We do not expect a C++ specialist, but you will encounter it.

Experience with modern front-end frameworks such as Vue.js, or the ability to pick one up quickly, alongside comfort working in traditional server-rendered front ends

5–8 years of professional software development experience

Experience conducting code reviews and mentoring other engineers

Experience in complex, multi-system or legacy-integrated environments

Experience with modern AI-assisted development tools such as Claude Code, Cursor or GitHub Copilot

Experience modernizing legacy systems or working in hybrid environments

Experience with mobile development frameworks such as React Native

Experience with UWP

Experience in regulated or compliance-driven environments, for example PCI

Experience working with government or public-sector customers

Experience with CI/CD pipelines, including building and maintaining automated build and release workflows

Azure cloud development experience, including cloud architecture and deploying and operating services in Azure

Deeper C++ experience in production systems

Knowledge, Skills and Abilities:

Ability to debug complex issues across multiple layers — database, backend and UI

Proven ability to design and implement maintainable, scalable systems

Strong collaboration across engineering, QA and product teams

Ability to take ownership of deliverables and drive work to completion

Ability to understand existing systems quickly and make safe, incremental improvements in production

We are looking for an object-oriented developer in the fullest sense: someone who designs with SOLID principles in mind and writes code that others can safely change.

Demonstrated understanding of reliability, scalability, security and maintainability, and the judgment to know which matters most in a given change.

Working knowledge of OWASP secure coding practices

Work Environment

Office setting with a moderate noise level.

The employee will work at an individual workstation, using a telephone and computer.

Physical Demands

Must be able to remain seated for extended periods.

Regular use of a computer and other office machinery, such as printers and copy machines.

Occasional movement around the office.

Frequent communication via telephone.

Neumo Summary

With the backing of four decades of public sector expertise and corporate capability, Neumo has successfully supported government services. Neumo was honored and recognized for four (4) consecutive years as a GovTech 100 Company representing the top 100 companies focused on making a difference in and selling to state and local government agencies across the United States.

Neumo is committed to helping communities thrive and brings a wealth of experience combined with innovation. Today, Neumo offers more administrative and financial support to government officials than any other organization. And with a responsive, client-focused approach, we foster partnerships that give our customers the certainty they need to accomplish more.

Neumo offers a competitive benefits and compensation package and are looking for team members who will thrive in our dynamic environment.

Neumo is an Equal Opportunity Employer. Selection for a position will be made without regard to race, religion, national origin, sex, political affiliation, marital status, non-disqualifying physical handicap,