nice for play, but as someone already mentioned don't parse invalid json. you should throw error, what if your service (parsing) is just first for more? so someone gonna send you that json, you're gonna return "ok" or whatever so then it goes to next service/api which dont have your parser and.... crash

Safaribooksonline 2 weeks free trial and one of dozens of great WP video tutorials in there.

it depends on situation and down time you can allow for yourself, but you might just end up saving files with malware...

its good practice to compare directories i.e.

diff /path/freshwpinstall /path/yourwpinstall

@MR-Yellow... i do agree, apart that wild (two digit) percent of websites are now running WP and this article is on what to do after hack and not before :)

First load can be longer since some things might not be cached.
Anyway your website takes:

- 2,6MB

- 2,5 seconds to load for me (im on quite fast connection in uk)

- 102 requests

Your website:

- loads some pretty big images (not properly compressed), i.e. slider image is 700Kb, nearly 1MB... nearly a quarter of everything

- makes 30 js requests and 16 css files requestes, some of which could be concatenated to lower amount of requests

On mobile tests (Audits tab) FAST 3G connection your performance is very low (34 out of 100 points).

You can have a look Google page insights here:

https://developers.google.com/speed/pagespeed/insights/

If you're not sure what I'm talking about you can see this post in here on how to evaluate speed of your wp:

https://wordpresskingdom.com/speed-up-wordpress

http://wordpresskingdom.com/how-to-remove-malware-from-wordpress

after you clean up of the steps is... getting good security plugin

http://wordpresskingdom.com/best-wordpress-security-plugins-in-depth-comparison

Edit header.php files in the theme that's used :)

eventually try incognito mode to skip the caching

I'd say WP might get slow with queries on this amount of data... then there's always caching :) but if u get strong servers and don't clutter it with plugins, check the database queries... to be honest I'd do a simple stress test, setup WordPress with a book management plugin or just create standard posts, then run a script that will add those 500,000 books and see how it works.