Why does one constant holds the site origin, and nothing else hardcodes it matter?

A domain literal scattered across 40 files is why staging URLs leak into production canonicals and why a domain migration takes a week. One constant makes it a one-line change. Verify it: Run `grep -rn 'https://yourdomain' --include='*.ts' --include='*.tsx' . | grep -v node_modules | grep -v lib/brand.ts` and confirm the result is empty.

Why does one canonical host, with a permanent redirect from the other matter?

Serving the same content on the apex and the www subdomain splits link equity and doubles the crawl budget spent on identical pages. Verify it: Run `curl -sI https://example.com | grep -i '^location'` and confirm a 301 to the canonical host. Then run the reverse and confirm it returns 200, not a redirect loop.

Why does hTTPS everywhere, with HSTS and no mixed content matter?

A single http asset on an https page blocks the padlock and, in modern browsers, is blocked outright. HSTS removes the redirect hop on every repeat visit. Verify it: Run `curl -sI https://example.com | grep -i strict-transport-security` and confirm a max-age of at least 31536000 with includeSubDomains.

Why does one trailing-slash policy, enforced by redirect matter?

`/about` and `/about/` are different URLs to a crawler. Serving both with 200 creates a duplicate for every page on the site. Verify it: Run `curl -sI https://example.com/about/ | head -1` and confirm a 301 to the canonical form (or the reverse, consistently).

Why does a missing page returns a real 404 status, not a 200 with an error message matter?

A soft 404 gets indexed. Google then treats an unknown share of your site as thin content, and the pages compete with the real ones. Verify it: Run `curl -s -o /dev/null -w '%{http_code}\n' https://example.com/this-does-not-exist` and confirm it prints 404.

Foundation

Foundation covers 5 of the SEO for Solos checklist's implementation checks. The base layer every other check assumes. Get these wrong and nothing above them can work.

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Foundation

The base layer every other check assumes. Get these wrong and nothing above them can work.

One constant holds the site origin, and nothing else hardcodes it3/S
Why it matters
A domain literal scattered across 40 files is why staging URLs leak into production canonicals and why a domain migration takes a week. One constant makes it a one-line change.
How to verify
grep -rn 'https://yourdomain' --include='*.ts' --include='*.tsx' . | grep -v node_modules | grep -v lib/brand.ts
Then confirm the result is empty.
found-single-site-urlImpact 3/5SmallRead the chapter
One canonical host, with a permanent redirect from the other4/S
Why it matters
Serving the same content on the apex and the www subdomain splits link equity and doubles the crawl budget spent on identical pages.
How to verify
curl -sI https://example.com | grep -i '^location'
Then confirm a 301 to the canonical host. Then run the reverse and confirm it returns 200, not a redirect loop.
found-canonical-hostImpact 4/5SmallRead the chapter
HTTPS everywhere, with HSTS and no mixed content3/S
Why it matters
A single http asset on an https page blocks the padlock and, in modern browsers, is blocked outright. HSTS removes the redirect hop on every repeat visit.
How to verify
curl -sI https://example.com | grep -i strict-transport-security
Then confirm a max-age of at least 31536000 with includeSubDomains.
found-https-everywhereImpact 3/5SmallRead the chapter
One trailing-slash policy, enforced by redirect3/S
Why it matters
`/about` and `/about/` are different URLs to a crawler. Serving both with 200 creates a duplicate for every page on the site.
How to verify
curl -sI https://example.com/about/ | head -1
Then confirm a 301 to the canonical form (or the reverse, consistently).
found-trailing-slash-policyImpact 3/5SmallRead the chapter
A missing page returns a real 404 status, not a 200 with an error message4/S
Why it matters
A soft 404 gets indexed. Google then treats an unknown share of your site as thin content, and the pages compete with the real ones.
How to verify
curl -s -o /dev/null -w '%{http_code}\n' https://example.com/this-does-not-exist
Then confirm it prints 404.
found-404-returns-404Impact 4/5SmallRead the chapter