Week 02 · Crawl controls
robots-outage · dirty-sitemaps · facet-explosion
Technical SEO training environment
Make the site fail on purpose.
Use the protected switches below to activate one issue family, load a repeatable weekly scenario, crawl the live site, diagnose the problem, and restore the clean baseline.
Current mode: clean · Active configuration: clean
Repeatable curriculum paths
Load a week
Presets activate a known issue bundle. Use one for a focused exercise, then restore the clean baseline.
Week 03 · Indexation and canonicals
canonical-conflict · soft-404 · thin-programmatic
Week 07 · JavaScript and structured data
csr-invisibility · schema-mismatch · cwv-regression
Week 11 · Migrations and data
migration-defects · data-join-mismatch · bot-errors
Issue families
Individual switches
Each switch changes the server-side state used by the crawlable site, APIs, redirects, metadata, and sitemaps.
Robots outage
The marketplace is accidentally disallowed after a release.
Sitemap contamination
Redirects, noindex URLs, and parameter variants leak into the sitemap.
Canonical collapse
Product canonicals point back to the marketplace category.
Soft 404 cohort
Empty generated pages return 200 with thin boilerplate.
Facet explosion
Every filter combination becomes crawlable and self-canonical.
CSR invisibility
Core product copy appears only after client JavaScript runs.
Schema mismatch
Price, availability, and reviews disagree with the visible page.
Core Web Vitals regression
Hero discovery, filtering tasks, and image sizing create measurable failures.
Mobile parity gap
Mobile removes critical product discovery links.
Hreflang conflict
Localized pages canonicalize to English and reciprocity breaks.
Bot reliability incident
Synthetic bot traffic encounters 429 and 503 bursts.
Thin page factory
Incomplete records publish without a quality gate.
Monitoring gap
Robots, canonicals, and sitemaps can regress without alerts.
Migration defects
Legacy routes contain gaps, chains, and irrelevant destinations.
Data join mismatch
URL keys differ by host, slash, encoding, and parameters.
Governance gap
SEO-critical fields have no accountable owner or release gate.
Entity conflicts
Company and product facts vary across site and profile surfaces.
Safe reset
Return to clean baseline
This disables every seeded issue and changes the mode back to clean. No rebuild or Vercel redeploy is required.
Use only synthetic data. Keep production customer information, credentials, and private routes out of this lab.