Erlang OTP 21.3 is released

March 13, 2019 · by Henrik Nord

OTP 21.3 #

Erlang/OTP 21.3 is the third service release for version 21 release with, improvements as well as a few features!

Highlights #


  • The standard logger handler, logger_std_h, now has a new internal feature for log rotation. For full information see the documentation.


  • The Reason part of the error return from the functions connect and handshake has a better and documented format. This is a potential incompatibility. See the documentation.
  • Refactoring of state handling has improved the TLS application data throughput and reduced CPU overhead
  • Code optimizations has reduced CPU load for encryption/decryption, especially for Erlang’s distribution protocol over TLS
  • Now supports active N


  • Support for plugin of a user supplied socket implementation has been added.


  • The HTML reference documentation now shows the OTP version where modules and functions were first introduced.
  • Versions of OTP older than R13B04 is not shown in the reference documentation

For a full list of details see:

Pre built versions for Windows can be fetched here:

Online documentation can be browsed here:

The Erlang/OTP source can also be found at GitHub on the official Erlang repository, Here: OTP-21.2

Please report any new issues via Erlang/OTPs public issue tracker https://bugs.erlang.orgWe want to thank all of those who sent us patches, suggestions and bugreports! Thank you! The Erlang/OTP Team at Ericsson