@BayuAngora, the changes fool is talking about above are not automatic. This post is recommending that you do builds in a certain way, but it doesn’t go into detail about how to do this.
If every file is being changed with every build, we recommend modifying the build so that it no longer does this. However, what to change is not “one size fits all”. Different sites and static site generators (SSGs) will require different solutions.
This post is suggesting that, for example, the site build does not add a build hash to files or filenames. Netlify automatically hashes files and will automatically invalidate the cache of any files which change.
For sites deployed with Netlify, the hash of the page is tracked as using an etag header and, if there are any changes to any deployed file - Netlify invalidates any cache version files automatically - even versions in the local browser cache for people visiting the site.
Some build tools and SSGs add a unique hash to each page with the build id - even if the page would otherwise contain no changes. This is great if you want to force cache invalidation - but that is the point - with Netlify you don’t want to force cache invalidation.
If the files didn’t change, using the cached version will be the best user experience and give the best site performance. This is why we created this topic - to make sure sites are using our CDN/ADN caching in the best way possible.
If there are other questions about this, please let us know.