What exactly is the latest node js version supported?

[Hetnon]

My app is built on version 20.8.0 but I'm not sure if that's supported on app engine. 
The documentation is not clear about it too.

Thanks!

[NoCommandLine]

If you're referring to App Engine standard, then according to the documentation

1. The NodeJs version in your app.yaml file will be the major version i.e. 20 (in your case) 
2.  The Node.js runtime uses the latest stable release of the version that is specified in your app.yaml According to this, I think that would be 20.10.0
3. App Engine automatically updates to new patch and minor release versions, but it will not automatically update the major version. 
   For example, your application might be deployed at Node.js 10.9.4 and later automatically updated to version 10.10.0,
   
   So if 20.8.0 was the stable release when your App was deployed, it would be automatically updated to 20.10.0 when that became available.

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