About Dave Cross

Dave Cross is a Perl consultant and trainer. He's been known to write a bit too. He has a Perl blog and you can follow him on Twitter.
Perl

When Random Isn’t Random Enough

We have a large automatic test suite here at Net-a-Porter, and that test suite gets run automatically whenever we check code changes in to our source code repository. Of course, a developer will run the suite manually before checking in changes, but it’s nice for the rest of the team to be able to see that a particular change hasn’t broken anything.

Occasionally, the test suite will flag problems that weren’t introduced with the most recent code change. This can get frustrating for the poor developer who gets the blame for breaking something that she didn’t touch. So when we find strange problems like this, we try to fix them; this is how we fixed one this morning.

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Perl

Understand Plack and PSGI

[Some notes on a talk given by Peter Sergeant]

Back in ancient history, when people started creating dynamic web pages, the CGI specification was born. It defined the interface between the web server and the program that was generating the page. The program read input from STDIN and the environment, and wrote output to STDOUT.

CGI turned out to be a rather slow way to generate dynamic pages. So, people developed faster methods such as mod_perl and fastcgi. Each of these had different interfaces. This made it hard, for example, to take a CGI application and run it under mod_perl,

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