Per this thread:
https://groups.google.com/forum/#!searchin/clojurescript/preamble/clojurescript/rUIlLfcYZvE/Yskfh4znL_0J
1) reamble 's value will be a vector of paths
2) the compiled output is prepended with the contents of the files at those paths
3) the generated source map points to the correct/adjusted line numbers
Additionally, when compiling for the :nodejs target the preamble contents will default to the hashbang we currently write in that situation.
Could the issue (and patch) be expanded to also support a ostamble option?
With both reamble and ostamble options available, it would be easy to implement more sophisticated compiler-output wrappers, such as the one used by David Nolen's mori library (which I helped adapt from the Q javascript library).
See: https://github.com/swannodette/mori/blob/master/support/wrapper.js
I'm fine with extending this to {ostamble}.
Oops resolved wrong ticket
fixed, https://github.com/clojure/clojurescript/commit/136bf46c656265a93dd15c40925f11edb34bd127.
If someone wants to open a postamble ticket and attach a patch go for it.