Thomas Rayner

Senior Security Software Engineer at Microsoft, CISSP

I’m a software developer with over 20 years of experience in languages (most recently in C#, TypeScript, Go, KQL), identity (authn/authz), x509 certificates and secret management, secure software supply chain, cloud architecture, and helping my teammates grow and succeed.

I am a prominent speaker, best-selling author, and teacher. I am very active within the technical community and a variety of Microsoft technical and strategic teams.

Work

Senior Security Software Engineer

– Present
Redmond, Washington

2025-Present - M365 Security Design and implement scalable cloud-based security solutions for Microsoft 365 services. 2021-2025 - IC3 Centrally remediate security issues for and provide horizontal support for 100+ teams responsible for the Microsoft Teams backend microservices. 2018-2021 (PRSS) Software development, deployment, change management, and automation subject matter expert on Gaming Crypto Services team in the Edge & Security Services organization.

  • (M365 Security) Design and implement scalable cloud-based security solutions for Microsoft 365 services, delivering value to billions of monthly active customers and hundreds of peers.

  • (M365 Security) Build and maintain host-based agents and cloud services to enforce seucrity policies across Azure on Windows and Linux.

  • (M365 Security) Develop cloud-scale data platforms to strengthen Microsoft's security posture.

  • (IC3) x509 certificate management, authentication & authorization (authn/authz) subject matter expert.

  • (IC3) Mentor and educate teammates regarding software development, x509 certificates, authn/authz, and other areas of subject matter expertise.

  • (IC3) Lead high impact security change campaigns across the 2000 person organization, delivering value to millions of monthly active customers and hundreds of peers.

  • (IC3) Empower peers and leaders to make informed, data-driven security decisions by creating concise dashboards and reports based on extremely large, disparate datasets.

  • (IC3) Inner-source contributions to a variety of Microsoft security products and services.

  • (PRSS) Responsible for continuous integration and delivery (CI/CD) platform servicing high security (HBI) environments.

  • (PRSS) Mentor and educate teammates regarding software development and other areas of subject matter expertise.

  • (PRSS) Led cultural change from traditional ops to DevOps, achieving goals of delivering more quickly, consistently, and making this paradigm more accessible for every teammate.

Software Developer

Edmonton, Alberta, Canada

Orchestrated robust CI/CD pipelines, automated scalable deployments, and built monitoring tools to streamline operations and elevate cross-team productivity.

  • Created and led strategies for continuous integration and delivery (CI/CD) to both on-premises and cloud-based infrastructure.

  • Developed automated dynamic environments and deployment strategies for existing and new services.

  • Developed and maintained tools and monitoring systems to improve workflows of other teams.

Author

Edmonton, Alberta, Canada

Contract author, solely responsible for creating and delivering online learning content.

  • Created learning paths for technology students.

  • Developed, recorded, edited, and distributed courses.

Instructor

Edmonton, Alberta, Canada

Undergraduate program instructor covering topics including leadership, network protocols, software development, server operating systems, project management.

Senior Systems Administrator

Edmonton, Alberta, Canada

Pioneer cultural and workflow changes related to systems administration, software development, and incident response.

  • Led development and automation efforts, saving organization tens of thousands of hours annually.

  • Mentored team, led and participated in escalation and major incident handling, key advisor in hiring and technology strategy decisions.

Principal Software Developer

Kastom Media
Edmonton, Alberta, Canada

Technical lead, software developer, and business development lead for a small web development company.

  • Designed and built diverse and varied web services for contract clients, predominantly on Linux, Apache, MySQL, PHP (LAMP stack), and JavaScript.

  • Perform contracted business development, process improvement, marketing strategy, and research activities.

Software Analyst

Edmonton, Alberta, Canada

Deliver special projects and provide support for the District’s software development team.

  • Managed complex projects, worked with users to troubleshoot line of business applications and a variety of Microsoft enterprise products.

  • Created and delivered training materials for District move to Google Mail/Apps from Exchange.

Other Positions, Internships

Aslan Computer Systems, Bolt Security Systems, Shaw Cablesystems
Edmonton, Alberta, Canada

Built, troubleshot and maintained applications and systems, remotely programmed client systems, worked with customers to resolve specific issues.

Education

NAIT

Technology Management

Bachelor of Technology

NAIT

Network Management

Bachelor of Applied Information Systems Technology

NAIT

Information Technology

Network Engineering Technology

Awards

Microsoft MVP

Awarded by Microsoft

Awarded Microsoft MVP award for fourth consecutive year. Last award because I joined Microsoft and employees are ineligible for this award.

Microsoft MVP

Awarded by Microsoft

Awarded Microsoft MVP award for third consecutive year.

Honorary Scripting Guy

Awarded by Hey, Scripting Guy! - Microsoft

From the Honorary Scripting Guy award announcement: What does it take to become an official Honorary Scripting Guy? It takes an extreme commitment to the scripting community, a remarkable dedication that helps to spread the good word about Windows PowerShell, and a relentless pursuit of excellence in producing exceptional content.

Microsoft MVP

Awarded by Microsoft

Awarded Microsoft MVP award for second consecutive year.

Microsoft MVP

Awarded by Microsoft

For more than two decades, Microsoft has recognized exceptional, independent community leaders who share their passion, technical expertise, and real-world knowledge of Microsoft products with others. It is part of Microsoft’s commitment to supporting and enriching technical communities.

Microsoft Most Valuable Professionals, or MVPs are exceptional community leaders who actively share their high-quality, real-world deep technical expertise with the community and with Microsoft. They are committed to helping others get the most out of their experience with Microsoft products and technologies.

Certificates

Certified Information Systems Security Professional (CISSP)

Issued by (ISC)²

Publications

thomasrayner.ca

Published by Personal Blog

Discussions and posts on software development and information security.

Skills

Information Security

  • x509 Certificates/Public Key Infrastructure (PKI)
  • Public Key Cryptography
  • Authentication (authn)
  • Authorization (authz)
  • Secure Software Development
  • Internet Security
  • Identity and Access Management (IAM)
  • Multi-factor Authentication (MFA)

Software Development

  • C#
  • TypeScript
  • Golang
  • KQL
  • PowerShell
  • Python
  • .NET
  • JavaScript
  • Code Review

Cloud Architecture

  • Azure
  • AWS (Intermediate)

DevOps

  • Continuous Integration (CI)
  • Continuous Delivery (CD)
  • Infrastructure as Code (IaC)
  • Configuration Management
  • Github Actions
  • Open Source
  • Azure DevOps
  • Monitoring

Leadership

  • Mentoring
  • Coaching
  • Teaching
  • Public Speaking

Enterprise Tools

  • Git
  • Github
  • Azure DevOps
  • Productivity Tools/Applications

Languages

English

Native Speaker

Interests

Personal Time

  • Hiking
  • Wine
  • Marksmanship
  • Cats

Personal Study

  • Data Science
  • AI/Machine Learning
  • Trying new languages