Sidecar SEO
The sidecar setup hosts SEO content produced for a client on dedicated infrastructure, served under their domain via a reverse-proxied subfolder. The client’s original site is left entirely untouched.
In practice
The advantage is twofold: no risky intervention on an existing site — often fragile or locked by a third-party provider — and fully controlled performance on the new section. The subfolder inherits the main domain’s authority, unlike a subdomain which would need to rebuild it from a much lower baseline.