Platform Engineering

We regularly write about our technical experiences (good and bad) and what we're learning from the market.


    Justin Yoo

    Justin Yoo
    Justin is a specialist manager at Deloitte Australia. He writes and speaks topics on any cloud related ones. He has been a Microsoft MVP since 2015.
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    Recent Posts

    6 Ways Passing Secrets to ARM Templates

    Posted by Justin Yoo on 24 April 2019

    Azure Resource Manager, ARM Templates, DevOps, Azure Key Vault, Azure Pipelines, YARM CLI, Azure DevOps, Linked Templates

    Whenever you deal with ARM templates, you always face to handle some sensitive information. This is mainly for API keys handling. How can you cope with those values other than hard-code them into the templates? There are six different ways to handle them we’re going to discuss in this post.

    1. Use ARM Template...

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    Performing Constructor Injections on Azure Functions V2

    Posted by Justin Yoo on 22 February 2019

    Azure Functions, Dependency Injection, Constructor Injection, Testability

    In January 2019, Azure Functions Team has released a new version of its runtime, 2.0.12265.

    I wasn’t able to believe what that meant at the first place.

    Does that mean we now can get rid of the infamous static modifier from both classes and methods?

    In fact, Fabio from Azure Functions Team showed a demo at Ignite...

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    Writing ARM Templates in YAML

    Posted by Justin Yoo on 07 August 2018

    CICD, JSON, VSTS, ARM Templates, Testing, Pester, Blog, Technology, YAML

    In my previous post, ARM Template Lifecycle Management: DOs and DON’Ts, I recommend to consider YAML for ARM template authoring. In the post, I also suggest using yarm to convert YAML to JSON and/or vice-versa. However, yarm is not that easy to use because it has to be deployed to Azure or, at least, it has to be run...

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    Testing ARM Templates with Pester #2 – Azure CLI

    Posted by Justin Yoo on 11 July 2018

    Architecture, VSTS, ARM Templates, Azure PowerShell, Testing, Pester, Blog, Technology, Azure CLI

    In my previous post, Testing ARM Templates with Pester #1 – PowerShell, I showed how to test behaviours ARM template deployment without actual deployment. At the end of the post, I also briefly mentioned how we can integrate this testing into our CI/CD pipeline. However, I was actually asked many times how I did it on

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    ARM Template Lifecycle Management: DOs and DON'Ts

    Posted by Justin Yoo on 18 June 2018

    Architecture, ARM Templates, DevOps, Article, Technology, Best Practice


    Are you an experienced DevOps engineer or managing cloud resources on Azure, or about to jump into Azure resource management?

    While you are creating, updating or deleting resources on Azure, you must have worked with Azure Resource Manager that keeps all resource definitions known as ARM templates. In...

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    Separation of Concerns: Logic App from ARM Template

    Posted by Justin Yoo on 13 June 2018

    Architecture, Logic Apps, ARM Templates, Blog, Technology, Latest Post, Separation of Concerns


    Azure Logic App is a set of workflow definitions, which is written in JSON format. The nature of JSON object results in this being tightly bound with ARM template. In other words, the Logic App has a dependency on an ARM template. Due to these characteristics, when any update is made on the workflow, the...

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    Dependency Injections on Azure Functions V2

    Posted by Justin Yoo on 06 April 2018

    Azure Functions, Blog, Technology, V2, ASP.NET Core, Dependency Injection

    Dependency Injections on Azure Functions are not very intuitive. I’ve written many blog posts about dependency management on Azure Functions to improve testability and this was my latest one. However, they are mostly about V1, which supports .NET Framework. Azure Functions V2 is now on public preview and I’m going to...

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    Cosmos DB in Azure Functions V1 and V2

    Posted by Justin Yoo on 19 February 2018

    Azure Functions, Cosmos DB, Blog, Technology

    As one of serverless families in Azure, Cosms DB is becoming very popular. In many development scenarios, Cosmos DB actually replaces existing RDBMS because it requires relatively lower cost for maintenance, and is easy to use. Another serverless family, Azure Functions, also provides triggers and bindings for Cosmos...

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    Converting UTC to Local Time via Azure Functions and Logic Apps

    Posted by Justin Yoo on 05 February 2018

    Azure Functions, Logic Apps, UTC, Time Zone, Blog, Technology

    In many information system development scenarios, including integration scenarios, handling date/time value is always problematic. If your information systems reside in your office or data centre located in your area, that won’t bring about too much trouble. However, if your organisation runs applications in several...
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    Testing ARM Templates with Pester #1 - PowerShell

    Posted by Justin Yoo on 22 January 2018

    ARM Templates, Testing, Pester, Blog, Technology

    ARM template is a great tool for Azure resources deployment. However, it’s very tricky to use because:

    • It’s a JSON object with massive number of lines,
    • Its JSON structure is quite complex so that it’s not that easy to read at a glance,
    • It’s hard to validate if there is a typo or not, and
    • We only know if the resource...
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