SOP: get canonicals right at scale

SOP: get canonicals right at scale
One wrong rule canonicalizes 40,000 pages into oblivion.

— Step 1 (Dev): Every indexable page self-canonicalizes to its absolute production URL. Gate: relative or wrong-host canonical → fail.
— Step 2 (Dev): Filtered/sorted/paginated variants canonicalize to the clean base view. Gate: a filter that changes primary content gets its own canonical, not the base.
— Step 3 (SEO): Pagination uses self-canonicals per page (not page 1) plus clear internal links. Gate: page 2 canonicalizing to page 1 → fail.
— Step 4 (Dev): Canonical, og:url, and the URL in your sitemap must be byte-identical. Gate: any of the three disagrees → fix.
— Step 5 (Ops): Audit a sample in Search Console — Google's chosen canonical should match yours. Gate: mismatch on >5% → investigate the rule.

Guardrail: never mix canonical and noindex on the same page.

Ship gate: don't publish until all boxes are checked.