This is Perl module Plack::Middleware::Expires. INSTALLATION Plack::Middleware::Expires installation is straightforward. If your CPAN shell is set up, you should just be able to do % cpan Plack::Middleware::Expires Download it, unpack it, then build it as per the usual: % perl Makefile.PL % make && make test Then install it: % make install DOCUMENTATION Plack::Middleware::Expires documentation is available as in POD. So you can do: % perldoc Plack::Middleware::Expires to read the documentation online with your favorite pager. Masahiro Nagano