If you set the precompile_only_if_changed option as true it will precompile Rails assets only if there are any changes since the last release. This option is disabled by default.
This pull request passes (merged 1719fbda into 30a942c).
New Rails assets option: precompile_only_if_changed
@huynguyen fixed /cc @ndbroadbent
@kirs This issue is more complicated than it seems. See the discussion at #227.