Announcing "Pester for Beginners" — the whole 25-part series, all at once
- PowerShell
- Testing
- DevOps
- Beginners
I'm genuinely excited to finally share something I've been working on offline for a while: a full blog series on testing PowerShell with Pester.
If you've ever gone looking for a tutorial series online, you know the feeling I'm trying to avoid. You find a promising "Part 1," it's good, you get invested — and then the trail goes cold at Part 3. The series was never finished. I've hit that wall more times than I can count, and I didn't want to do that to anyone.
So I made a decision early on: I wasn't going to publish this piece by piece and hope I kept up. I'd finish the entire series first, then release it all at once. I wrote these across the spring — each post is dated when I wrote it, starting back in early March — and today the whole set goes out together. Nothing is half-done. You can start at Part 1 right now and read straight through to the end without waiting on me.
What the series covers
It's called Pester for Beginners, and it's exactly that — a path from "I've never written a test" to "I write, mock, measure, and automate Pester tests with confidence." It's 25 parts, grouped into six sections, and the numbered order is the recommended reading order. Each post builds on the ones before it.
All examples use Pester 5.x (the current major line), and every code block is meant to be copy-paste runnable. It's vendor-neutral — no product pitch, just Pester.
Here are the six sections:
- Foundations: Why & First Steps — what Pester is, getting it installed (and untangling the old v3/v4 vs v5 confusion), and writing and running your first passing test.
- Assertions: Making Tests Mean Something — the
Shouldcommand, comparing values and collections, testing for failures withShould -Throw, and negating cleanly. - Structure: Organizing a Test Suite —
DescribevsContextvsIt, setup and teardown, Arrange–Act–Assert, and file/naming conventions. - Testing Real Code — getting your own functions under test, safe file/registry tests with
TestDriveandTestRegistry, data-driven tests, and filtering which tests run. - Mocking & Isolation — what mocking actually is, the
Mockbasics, proving interactions withShould -Invoke, targeted mocks, and the pitfalls that catch people. - Quality & Automation — measuring code coverage, configuring runs with
New-PesterConfiguration, running Pester in CI/CD, and a capstone that ties it all into a TDD habit.
Each post follows the same shape — a hook, what you'll learn, runnable examples, a "try it yourself" exercise, common mistakes, and a recap — so it reads as one continuous voice whether you go front-to-back or treat it as a reference.
How to use it
If you're brand new to testing in PowerShell, start at Part 1 and work through in order. If you already know the basics and you're here for a specific topic — mocking, coverage, CI — jump straight to that section; the posts cross-link by part number so you won't get lost.
I'd love to hear from you
I hope you enjoy the series, and more than that, I hope it's genuinely helpful in your day-to-day work. That's the whole point of writing it.
Please feel free to send along any questions, comments, or concerns — at any time. I'm really looking forward to hearing how the series works for you, and whether it helps. If something is unclear, or you'd test a thing differently than I did, I want to know.
Thank you so much for reading, and take care.