log4js-node/docs/v3-changes.md

Changes in version 3.x of log4js

log4js no longer supports node versions less than 6.

The following appenders have been removed from the core, and moved to their own projects:

• gelf
• hipchat
• logFaces-HTTP
• logFaces-UDP
• loggly
• logstashHTTP
• logstashUDP
• mailgun
• rabbitmq
• redis
• slack
• smtp If you were using them, you'll need to npm i @log4js-node/<appender>.

Removing the optional appenders removed all the security vulnerabilities.

The TCP client/server was introduced to replace the multiprocess appender.

Issues resolved in 3.0.0 PR for the code changes