use HTTP::UserAgent;
use JSON::Tiny;

my $user-agent = HTTP::UserAgent.new;
$user-agent.timeout = 10;

my $response = $user-agent.get("http://xkcd.com/info.0.json");
my %content = from-json($response.content);
my $img = $user-agent.get(%content<img>, :b);
spurt "./test.png", $img, :b;