When I started Rebmu I followed along the pattern of having seen people put History: in the headers of files. And as it got longer, I kind of questioned the value of it.
I'm not sure what the "best practices" for history is, but it's a lot of stuff to skip over when you're trying to get to the meat of a file. It warrants its own discussion topic (which I guess can be discussed here, with the extracted history).
History: [
0.1.0 [10-Jan-2010 {Sketchy prototype written to cover only the
Roman Numeral example I worked through when coming up with the
idea. So very incomplete, more a proof of concept.}]
0.2.0 [22-Jun-2010 {Language more complete, includes examples.
Ditched concept of mushing symbols like + and - into single
character operators is removed due to realization that A+
B+ C+ etc. are more valuable in the symbol space than one
character for AD.}]
0.3.0 [24-Jun-2010 {Made backwards compatible with Rebol 2.
Note that things like CN for continue or PERCENTAGE! datatype
were added in Rebol 3. You can use these in your Rebmu programs
but they will only work if using Rebmu with an r3 interpreter.
Also did several name tweaks like instead of AA for AND~ it's
now A~ along with other consistencies.}]
0.5.0 [16-Feb-2014 {Version bump to indicate growing maturity
of the language. Abandon Rebol 2 support. Rebmu files now
have proper Rebol ecology headers.}]
0.6.0 [6-Apr-2014 {Large cleanup creating incompatibility with
most all previous Rebmu code solutions. Examples have been updated
in GitHub. Major theme was removing the custom IF/UNLESS/EITHER
implementation and some clearer names.}]
0.7.0 [15-Sep-2015 {Project revisited to incorporate new ideas and
decisions from the Ren/C effort. Incorporates the rebol-proposals
module to work with experimental language features instead of
having its own "incubator" project. "Mu library" features removed
in favor of embracing the language default more closely.}]
]