Kirk Tolleshaug Senior Backend Software Engineer Vancouver, Washington, United States

Systems that stay fast
as the work gets complex.

I am Kirk Tolleshaug, a senior backend software engineer who builds reliable, high-performance systems, versioned APIs, and distributed services that scale.

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Impact

Engineering outcomes, not just implementation.

100M+

API requests each month

Built backend services, APIs, integrations, reporting workflows, and distributed processing across platforms serving tens of thousands of users and handling more than 100M API requests each month.

Hours → minutes

and minutes down to seconds

Found and removed bottlenecks in memory use, request processing, concurrency, and workload distribution.

~$30M

in annual infrastructure savings

Built reporting that exposed cloud spend and usage opportunities, enabling meaningful optimization decisions.

Experience

Hands-on delivery with room to lead.

I stay close to implementation while shaping technical direction, mentoring engineers, breaking down complex work, and delivering reliable systems across APIs, integrations, data, and cloud infrastructure.

  1. 2022 — Present

    Software Engineer

    Digital Monitoring Products

    • C# / .NET
    • Versioned APIs
    • RabbitMQ
    • Docker
    • New Relic
    • PostgreSQL
    • gRPC
    • AI-assisted engineering

    Design and optimize C#/.NET services and versioned public APIs for web, mobile, external integrations, tens of thousands of users, and millions of connected security devices. Build resilient RabbitMQ workflows, modernize legacy services, and improve performance and observability with Docker and New Relic. Use AI-assisted engineering tools to accelerate codebase analysis, defect investigation, and legacy modernization, with developer-owned validation through tests and code review.

  2. 2014 — 2022

    Senior Software Engineer

    Vizient, Inc.

    • C# / .NET
    • Azure
    • SQL Server
    • OAuth / SSO
    • Entity Framework
    • Terraform
    • CI/CD

    Progressed from intern to senior engineer while owning delivery, mentoring engineers, and contributing across authentication, reporting, modernization, and Azure-hosted applications. Built internal OAuth/SSO services, cloud reporting that contributed to approximately $30M in annual savings, and reusable infrastructure and delivery automation.

  3. 2014 — 2015

    Teaching Assistant & WebParaprofessional

    Southeast Missouri State University

    • ASP.NET
    • C#
    • SQL Server
    • Entity Framework
    • IIS
    • Linux
    • Mentoring

    Supported computer science instruction and students while building ASP.NET/C# applications for university departments. Delivered a writing-lab sign-in and usage-tracking application and supported Moodle and instructional technology systems.

Work

A record of making complicated systems more useful.

01

Modernization & performance

Modernizing legacy systems with AI-assisted engineering.

Modernized legacy .NET services with Docker-based local stacks and New Relic observability. AI-assisted analysis helped map dependencies and guide refactoring, while developer-owned tests and code review kept changes safe. The work improved deployment reliability and reduced selected API response times from several seconds to sub-second performance.

  • Modern .NET
  • AI-assisted engineering
  • Docker
  • New Relic
  • CI/CD

02

High-volume event processing

Making real-time device workflows dependable at scale.

Built resilient event-driven device and job workflows using RabbitMQ, dead-letter queues, retries, idempotent API handling, distributed caching, and purpose-built integrations.

  • RabbitMQ
  • Event processing
  • API reliability
  • Distributed systems

03

Cloud intelligence

Turning cloud-usage data into business decisions.

Architected reporting that combined usage and cost data to identify unnecessary services and optimization opportunities across cloud infrastructure.

  • Azure
  • Reporting
  • Infrastructure
  • Technical ownership

Technical focus

Built for the systems behind the interface.

Languages & frameworks

C#, .NET, ASP.NET, Go, and Java for backend development; Angular and React for web application workflows.

APIs & distributed systems

REST APIs, API versioning, OpenAPI/Swagger, Azure API Management, event-driven architecture, gRPC, background services, multithreading, and parallel processing.

Reliability & observability

Idempotency, retries, dead-letter queues, structured logging with Serilog, New Relic, service-health metrics, and production diagnostics.

Data & messaging

SQL Server, PostgreSQL, Entity Framework, schema migrations, RabbitMQ, Redis, distributed caching, query tuning, and large transformations.

Cloud & delivery

Azure, AWS, Docker, App Services, Azure SQL, Functions, Key Vault, infrastructure as code with Terraform and Bicep, and CI/CD.

Security & quality

OAuth/SSO, JWT, roles and claims, service-to-service authentication, TDD, NUnit, xUnit, and unit, integration, end-to-end, and performance testing.

Resume

The essentials, in one place.

More than 12 years of professional software development across backend systems, APIs, cloud-hosted applications, distributed processing, observability, and legacy modernization.

Career focus

Hands-on senior backend engineering.

Most interested in roles that combine implementation with architecture, technical direction, modernization, and end-to-end delivery.

Education

Southeast Missouri State University

Bachelor of Science, General Studies
2011 — 2015

Certification

Azure Fundamentals

December 2021

Cloud-platform foundation across Azure-hosted applications, infrastructure, and delivery automation.

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Get in touch

Building a backend team that needs a steady hand?

For senior backend roles involving architecture, modernization, performance, and high-volume systems, I would be glad to talk.

Email is the best way to reach me.

[email protected] Download vCard