For developers studying web performance, Ilya Grigorik offers a technical blog providing deep dives on networking, browsers, engineering lessons, talks, and practical optimization ideas for faster sites.
No, igvita.com is a blog of technical information and resources, and not an online store with regular promo codes. Most likely, the visitors will get discounts using the archive of the free technical articles, slides and performance resources.
The greatest value of igvita.com is the archive of technical writings about web performance, networking, browsers, and developer tools. Many of the articles are written a while ago, but they are still helpful to learn the basics of web performance.
igvita.com is mostly an informational site; therefore, it does not act like a usual checkout site. Some posts could contain the references to the books, talks, tools, or external resources, but the purchases should be performed somewhere else.
Developers could use free educational content and then pay for additional courses or consultations elsewhere. igvita.com is perfect to learn the concepts that could enhance the website performance without buying any software.
There is no coupon-like membership program available on igvita.com. If you want to follow the author's work, it is better to check out the archive and social/professional pages of the author.
Many of the old articles are useful as the background materials, especially those which describe networking and browsers basics. For the rapidly changing tools and APIs, the reader should check out the official documents for the details.
The coupons should not be provided by coupon sites. A coupon page for igvita.com should concentrate on the free learning resources.