For more than two years the Message Format Working Group (MFWG) worked on developing an industry standard for the representation of localizable message strings to be a successor to ICU MessageFormat.

MFWG will recommend how to remove redundancies and pitfalls, make the syntax more usable, and support more complex features, such as gender, inflections, and speech. MFWG will also consider the integration of the new standard with programming environments, including, but not limited to, ICU, HTML, and ECMAScript, and with localization platform interchange. The output of MFWG will be a specification for the new syntax, which is expected to be on track to become a Unicode Technical Standard.

The reasoning for this effort is shared in the “Why MessageFormat needs a successor” document.

The project is hosted on GitHub (https://github.com/unicode-org/message-format-wg).

The current specification, which we want to implement and provide as a Tech Preview with ICU4J 72, is here:

https://github.com/unicode-org/message-format-wg/blob/develop/spec/syntax.md