Azure App Service: Extracting a 60MB node_modules ZIP takes longer than running npm install —...

I have an automated deployment tool that generates a React or Angular project, uploads it to Azure App Service, and then restores node_modules to reduce build time.

To avoid running npm install on every deployment, I store a prebuilt node_modules.zip (~60 MB) in Azure Blob Storage.
My workflow is:

1. 
   Download node_modules.zip
   
   
2. 
   Extract it inside Kudu (App Service console) under /tmp/...
   
   
3. 
   Copy the extracted folder to /home/site/wwwroot/<project>/node_modules
   

The problem:
Extracting + copying this ZIP takes more time than running npm install, even though the whole idea was to speed up deployment.

What I tried

• 
  Using node_modules.zip
  
  
• 
  Extracting to /tmp then copying to the project directory
  
  
• 
  Trying different unzip packages (unzipper, adm-zip, etc.)
  
  
• 
  Using Kudu console and Azure CLI
  

Issues Observed

• 
  Azure App Service file system is slow with thousands of small files
  
  
• 
  Zip extraction of node_modules is extremely slow
  
  
• 
  Copying the folder doubles the delay
  
  
• 
  End result: npm install actually finishes faster
  
  My Question
  
  How can I speed up the node_modules restore process on Azure App Service?
  
  I want to avoid running npm install every time, but extracting a ZIP of node_modules is even slower. What’s the best practice to quickly restore dependencies on Azure App Service?
  
  Additional Notes
  
  • 
    App Service is Linux-based
    
    
  • 
    Deployment tool is using Node.js
    
    
  • 
    React and Angular builds are working, this issue is only with node_modules restore
    
    
  • 
    I am open to alternatives like tar.gz, npm cache, npm ci, etc.
    
  What I am looking for
  
  • 
    Better format to store node_modules (tar.gz?)
    
    
  • 
    Faster extraction method
    
    
  • 
    Extract directly to destination without copy?
    
    
  • 
    Alternative approaches (npm cache or npm ci)
    
    
  • 
    Any best practices for dependency restore in Azure App Services
    

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