The proper way to create JSON strings is to first create a data structure in Perl that matches the desired output structure, and then run it through a JSON module like JSON or JSON::XS: 

use JSON qw/encode_json/;
my $data = {
   auth => {
      "RAX-KSKEY:apiKeyCredentials" => { 
          username => $USERNAME,
          apiKey   => $API_KEY,
       },
   },
};
my $json = encode_json($data);

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Perl 6 - the future is here, just unevenly distributed

In reply to Re: Interpolating variables in JSON string by moritz
in thread Interpolating variables in JSON string by reisinge

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