Hi! I think you had post this job before but, anyway, I'm writing again. I have plenty experience with Drupal optimization and server tuning. In your case, to try to achieve the 1~2 seconds goal, you will need to have access to server too, as there will be modifications to be made within Apache2 (I expect that you are already using Nginx instead), MySQL (MariaDB), Varnish, Memcache and other services that helps a lot the website to work better.
Also it would to be good if you provide a list with the bugs that you have to get rid off, and the features that your Drupal system has (if it is an e-commerce, if it is integrated with other website or API service, if it has Panels and Display Suite installed, what is the template used, etc.).
Two days is my deadline for real, considering heavy installations/modifications and then a great gain of performance, but I'll be observing and tweaking it all during a week more.
A little about me, my name is Marcelo and I'm from Brazil. I am a CS graduated with more than 17 years experience in IT market. I'm very experienced with server/application tuning for Drupal, Wordpress and Magento. I have some good works at my portfolio, and other minor websites to send you links if interested. I'm with 100% successful concluded projects here at Freelancer.com and I pretend to keep that.
If you are interested, then I hope to hear from you soon, call me on the chat or award my bid.
Regards,
Marcelo.
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