Senior .Net Software Engineer

Vaco; Tempe (AZ); On-site; USD 135,000 - 165,000; Full time

Benefits offered by this job

Bonus opportunity

401(k) with employer match

Generous PTO

Job summary

Vaco, in collaboration with a national wealth management technology leader, seeks a Senior Software Engineer focused on backend .NET development, API design, and modernization of core platform applications. Based in Tempe, you will join a new engineering team as one of the most senior individual contributors locally.

The role emphasizes rewriting legacy systems into modern .NET, building scalable APIs, working with SQL Server, and interfacing with multiple data sources.

Qualifications

• 7+ years of professional software engineering experience delivering production systems.
• Strong backend development experience with C#, .NET, and modern .NET frameworks.
• Experience modernizing legacy applications or incremental improvements of older systems.
• Strong SQL database experience, including SQL Server or comparable relational databases.
• Experience designing and building RESTful APIs and integration layers.
• Experience with third-party API integrations and data ingestion from multiple sources.
• Experience writing unit and integration tests and working within CI/CD delivery practices.
• Experience working in Agile or Scrum environments with cross-functional teams.
• Strong communication skills with the ability to explain technical decisions clearly.
• Ability to operate as a senior individual contributor and mentor other engineers.

Responsibilities

• Design, build, test, and deploy backend services and APIs using C#, .NET, and modern engineering practices
• Support modernization efforts by helping rewrite legacy systems into modern .NET architecture
• Develop scalable API and integration patterns for data ingestion across multiple internal and third-party sources
• Work with SQL Server and related database technologies to build reliable, data-centric applications
• Translate product requirements and architecture guidance into maintainable, production-ready software
• Author technical design documentation and participate in design reviews for significant changes
• Build resilient integrations with clear contracts, versioning strategies, error handling, logging, and observability
• Write clean, testable code and contribute to unit, integration, and end-to-end testing practices
• Participate in code reviews focused on performance, maintainability, resiliency, and secure coding
• Troubleshoot production issues, support root-cause analysis, and improve application reliability
• Partner with product, architecture, QA, DevOps, and engineering peers in Agile delivery cycles
• Mentor junior and mid-level engineers while helping raise engineering standards across the team

Skills

C#

NET Framework / .NET Core

RESTful APIs

SQL Server

CI/CD

Agile / Scrum

Mentoring

Unit testing

Tools

Azure

Azure SQL

Azure Functions

Azure API Management

AWS

Job description

Vaco is partnering with a national wealth management technology organization to hire a Senior Software Engineer focused on backend .NET development, API design, and modernization of core platform applications. This role will be part of a new Tempe-based engineering team and will serve as one of the most senior individual contributors locally.

The immediate focus is modernizing legacy applications, including rewriting older systems into modern .NET. This is a backend-heavy role centered on C#, .NET, SQL databases, API design, and integrations across multiple data sources and third-party systems. There may be some front-end exposure, but dedicated front-end developers handle most React work, so the strongest fit will be someone who is much deeper in backend engineering than UI development.

This role is based in Tempe and requires onsite presence four days per week.

What You'll Be Doing

• Design, build, test, and deploy backend services and APIs using C#, .NET, and modern engineering practices
• Support modernization efforts by helping rewrite legacy systems into modern .NET architecture
• Develop scalable API and integration patterns for data ingestion across multiple internal and third-party sources
• Work with SQL Server and related database technologies to build reliable, data-centric applications
• Translate product requirements and architecture guidance into maintainable, production-ready software
• Author technical design documentation and participate in design reviews for significant changes
• Build resilient integrations with clear contracts, versioning strategies, error handling, logging, and observability
• Write clean, testable code and contribute to unit, integration, and end-to-end testing practices
• Participate in code reviews focused on performance, maintainability, resiliency, and secure coding
• Troubleshoot production issues, support root-cause analysis, and improve application reliability
• Partner with product, architecture, QA, DevOps, and engineering peers in Agile delivery cycles
• Mentor junior and mid-level engineers while helping raise engineering standards across the team

Required Experience

• 7 or more years of professional software engineering experience delivering production systems
• Strong backend development experience with C#, .NET, and modern .NET frameworks
• Experience modernizing legacy applications or incrementally improving older systems
• Strong SQL database experience, including SQL Server or comparable relational databases
• Experience designing and building RESTful APIs and integration layers
• Experience with third-party API integrations and data ingestion from multiple sources
• Experience writing unit and integration tests and working within CI/CD delivery practices
• Experience working in Agile or Scrum environments with cross-functional teams
• Strong communication skills with the ability to explain technical decisions clearly
• Ability to operate as a senior individual contributor and mentor other engineers

Nice to Have

• Azure cloud experience, including App Services, Azure Functions, Azure SQL, Azure API Management, Azure Service Bus, Azure VMs, Cosmos DB, or Azure Storage
• AWS or other cloud platform experience
• Experience with .NET 8, .NET 9, or modern Microsoft application modernization efforts
• Exposure to React or ASP.NET front-end development
• Experience in financial services or another regulated industry
• Experience leading technical design reviews or guiding engineering standards

Compensation & Benefits

• Base salary up to $150,000, depending on experience
• 10% bonus opportunity
• 401(k) withemployer match
• Generous PTO

If you are a senior backend .NET engineer who enjoys modernization work, API design, and building reliable systems in a high-quality engineering environment, we would welcome the opportunity to connect.

EEO Notice

Vaco by Highspring is an Equal Opportunity Employer and does not discriminate against any employee or applicant for employment because of race (including but not limited to traits historically associated with race such as hair texture and hair style), color, sex (includes pregnancy or related conditions), religion or creed, national origin, citizenship, age, disability, status as a veteran, union membership, ethnicity, gender, gender identity, gender expression, sexual orientation, marital status, political affiliation, or any other protected characteristics as required by federal, state or local law.

Vaco by Highspring and its parents, affiliates, and subsidiaries are committed to the full inclusion of all qualified individuals. As part of this commitment, Vaco by Highspring and its parents, affiliates, and subsidiaries will ensure that persons with disabilities are provided reasonable accommodations. If reasonable accommodation is needed to participate in the job application or interview process, to perform essential job functions, and/or to receive other benefits and privileges of employment, please contact [e-mail].

Vaco by Highspring also wants all applicants to know their rights that workplace discrimination is illegal.