What is the problem this feature will solve?

zstd and the application/zstd media type were standardized in 2018 in RFC8478 (and refined in RFC8878). In the context of the web, support is becoming more widespread:

Browsers

• Chrome
  • Issue 1246971: Implement zstd content-encoding
  • Expected to land in 117
• Firefox
  • Bug 1301878: Implement support for Zstandard (zstd)
  • Still under discussion

Web servers

• Caddy
  • Available in v2
• Nginx
  • Available as a module

Tools

• cUrl
  • Available in 7.72.0
• wget2
  • Available in 1.99.2

What is the feature you are proposing to solve the problem?

Add support for zstd compression in Node's zlib module.

What alternatives have you considered?

No response