Its Day 98 of my 100 Days of Cloud journey and in todays post we’ll take a quick look at Azure Bicep.

Azure Bicep is a domain-specific language (DSL) that uses a declarative syntax to deploy Azure resources. In a Bicep file, you define the infrastructure you want to deploy to Azure, and then use that file throughout the development lifecycle to repeatedly deploy your infrastructure. Your resources are deployed in a consistent manner.
Bicep v JSON
We’ve seen Azure Resource Manager Templates and how they can be used to define your infrastructure based on JSON Templates. Bicep is part of the Azure Resource Managet Template family – the difference is that Bicep is a launguage that uses .bicep files instead of .json files.
If we take a look at the differences between the 2 – below is a JSON template where we want to deploy a Storage Account:

And here we have a Bicep file deploying the same storage account:

You can see the difference in file size and the simpler syntax in use with Bicep over JSON. However, when you build Bicep templates and perform a deployment operation, it will transpile into an ARM template, and then Resource Manager will go and deploy your resources to Azure. So effectively the runtime is unchanged; Bicep only provides an abstract layer and reduces the pain of working with JSON.

You can also use the Bicep Playground to view Bicep and equivalent JSON side by side. This will allow you can compare the implementations of the same infrastructure. You can also decompile an existing ARM template to Bicep, see Decompiling ARM template JSON to Bicep.
Benefits of Azure Bicep
- Authoring experience: When you use the Bicep Extension for VS Code to create your Bicep files, you get a first-class authoring experience. The editor provides rich type-safety, intellisense, and syntax validation.
- Repeatable results: Repeatedly deploy your infrastructure throughout the development lifecycle and have confidence your resources are deployed in a consistent manner. Bicep files are idempotent, which means you can deploy the same file many times and get the same resource types in the same state. You can develop one file that represents the desired state, rather than developing lots of separate files to represent updates.
- Orchestration: You don’t have to worry about the complexities of ordering operations. Resource Manager orchestrates the deployment of interdependent resources so they’re created in the correct order. When possible, Resource Manager deploys resources in parallel so your deployments finish faster than serial deployments. You deploy the file through one command, rather than through multiple imperative commands.
- Modularity: You can break your Bicep code into manageable parts by using modules. The module deploys a set of related resources. Modules enable you to reuse code and simplify development. Add the module to a Bicep file anytime you need to deploy those resources.
- Integration with Azure services: Bicep is integrated with Azure services such as Azure Policy, template specs, and Blueprints.
- Preview changes: You can use the what-if operation to get a preview of changes before deploying the Bicep file. With what-if, you see which resources will be created, updated, or deleted, and any resource properties that will be changed. The what-if operation checks the current state of your environment and eliminates the need to manage state.
- No state or state files to manage: All state is stored in Azure. Users can collaborate and have confidence their updates are handled as expected.
- No cost and open source: Bicep is completely free. You don’t have to pay for premium capabilities. It’s also supported by Microsoft support.
Limitations
- Limited to Azure — Bicep isn’t going to fly if someone is using multi-cloud and wants to use the same language across multiple cloud providers. This where Terraform has the advantage in this space.
- Learning Curve — Bicep is basically a new language that expects some learning and understanding in spite of being very simple. Most of the users can prefer to use JSON instead, and if you are familiar with traditional JSON ARM Templates you may decide to stick with that.
Conclusion
Azure Bicep is an exciting technology that promises to make deployments easier if you are using only Azure. There are some great resources out there to start your learning journey:
- Bicep Playground
- Decompiling ARM template JSON to Bicep
- Official Microsoft Docs Site
- Elkhan Yusubov’s Bicep Demo
- Tech Community Article by Luise Freese
- Microsoft Learn has lots of Bicep modules, but the Fundamentals of Bicep one is a good place to start.
Hope you all enjoyed this post, until next time!