doc/design/compiler-environment-support.md

Summary

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# Compiler environment support

**NOTE:** Compiler support does not dictate the runtime requirements of compiled code.

## Officially supported environments

The Babel compiler is **only** supported in these environments:

 - Modern browsers such as Chrome, Firefox, Safari, Edge etc.
 - Node.js 6 and newer versions

## Unsupported environments

This means that any other environment is not supported, this includes but is not limited
to:

 - Rhino
 - Nashorn
 - Internet Explorer

**NOTE:** If Babel works in any of the unsupported environments, it is purely
coincidental and has no bearing on future compatibility. Use at your own risk.