Fix Lag and Enhance Website Speed

I'm in need of a proficient web developer who can address some major performance issues with my website. Notably, the loading speed of the home page, about page, and product pages is extremely slow. The lag during background switching is also seriously hindering user experience.

Your main task will involve:

* Identifying the reasons behind the site's lagging and slow loading times
* Proposing and implementing effective solutions, ensuring the website's opening speed isn't compromised

I encourage you to detail your:

* Past WP-Based project history
* Experience dealing with similar issues
* Comprehensive proposals to improve site speed

I am yet to make any definite attempts to improve the website's loading speed, so you will have complete freedom to employ effective techniques be it image compression, caching implementation, or file minifications.

The ideal candidate will:

* Have extensive experience with WordPress
* Understand how to diagnose and address speed issues
* Have a background in web development, especially in improving website performance.