Senior .NET Support Engineer: Production Reliability

Tax App LLC; Los Angeles (CA); On-site; USD 120,000 - 180,000; Full time

Job summary

TaxApp is seeking an experienced Support Engineer to be the first line of help for TaxApp. You will work on site with staff and clients, digging into data, logs and code to explain and fix issues, whether data, configuration or bugs.

You’ll join a fast-paced team that relies on TaxApp to serve clients and uses AI tools to accelerate investigations. You’ll handle sign-ins, payments, e-signatures and reporting issues, with a focus on keeping TaxApp running smoothly.

Qualifications

• 5–10+ years of professional experience as a .NET engineer, supporting production apps.
• Strong SQL skills with joins, aggregates and window functions; PostgreSQL preferred.
• Solid C#/.NET skills with ASP.NET Core MVC and ability to trace through unfamiliar code.
• Experience with EF Core, migrations, and LINQ; identify data vs query bugs.
• Experience writing automated tests (xUnit or NUnit).
• Basic AWS knowledge; read CloudWatch logs and check service health.

Responsibilities

• Serve as the first contact for TaxApp problems from staff and clients on the portal.
• Triaging issues by business impact; prioritize payment problems, outages, privacy/compliance.
• Reproducing issues and classifying as bug, data problem, training question or feature request.
• Investigating data issues with SQL in PostgreSQL and applying careful fixes.
• Trace problems through C#/.NET code and locate matching logs in AWS CloudWatch.
• Check application health on AWS and perform approved actions per runbooks.
• Fix bugs in C#/.NET code, write tests, and submit PRs with clear descriptions.
• Coordinate with wider engineering for larger problems; provide evidence-based reports.
• Offer updates to staff on releases and maintain helpful runbooks and FAQs.
• Work with integrations and vendor dashboards to diagnose payment, bank, e-signature issues.

Skills

SQL proficiency

C#/.NET

Automated testing

Bug triage & debugging

Clear bug reports

AWS basics

Git/GitHub workflow

AI-assisted debugging

On-site collaboration

Communication under pressure

Tools

PostgreSQL

ASP.NET Core MVC

Entity Framework Core

xUnit/NUnit

CloudWatch

Docker (nice to have)

Jira/Linear/ClickUp

Job description

TaxApp is seeking an experienced Support Engineer to be the first line of help for TaxApp. You will work on site with staff and clients, digging into data, logs and code to explain and fix issues, whether data, configuration or bugs.

You’ll join a fast-paced team that relies on TaxApp to serve clients and uses AI tools to accelerate investigations. You’ll handle sign-ins, payments, e-signatures and reporting issues, with a focus on keeping TaxApp running smoothly.