List of free azure stuff for developer👇🏽
If you're looking for all programming tools around azure (not just free). Check this page List of azure Programming Tools

Leapp
Leapp is the App to access your cloud. It handles the management and security of your cloud credentials for you.
Tag: AWS, Azure, Security
Open Source

Azure Functions Serverless
Create event-driven, scalable serverless apps in .NET, Node.js, Python, Java, or PowerShell. Build and debug locally—deploy and operate at scale in the cloud.
Tag: serverless, azure
1 million requests / month

Virtual Machines Azure
Build Linux and Windows virtual machines (VMs) and save up to 80 percent with Azure Reserved Virtual Machine Instances and Azure Hybrid Benefit for Windows Server.
Tag: virtual-machine, azure, hosting-dynamic
1 Year free: 750 hours B1s burstable virtual machines/month