# Technical Reference

Source: [Technical Reference](https://typeroll.com/docs/technical/overview/)

> Implementation details for Typeroll-powered sites — what the renderer emits, what the deploy pipeline writes, and how the platform optimises for the web.

This section documents the technical contract Typeroll honours when it builds and serves a site. It’s a reference for self-hosters, agency engineers, and anyone curious about what’s actually under the hood — most customers never need it.

Topics covered:

* **[SEO & indexing](https://typeroll.com/docs/technical/seo-and-indexing/)** — canonical URLs, robots, sitemap, structured data, fallback-subdomain de-duplication, and how custom-domain activation affects all of the above.
* **Image optimisation** *(coming)* — how images move from upload through Cloudflare’s CDN into the page, what formats are served, caching behaviour.
* **Social media tags** *(coming)* — OpenGraph + Twitter card defaults, per-page overrides, image sizing.
* **Cache headers & deploy invalidation** *(coming)* — what the `_headers` file the deploy emits says, how to opt out, when stale assets matter.
* **Site security** *(coming)* — sanitiser behaviour, CSS scrubbing, iframe allow-list, what scripts can and can’t ship.

If something here disagrees with what you observe, the code wins — file an issue or fix it. The pages in this section are written to match the runner / renderer behaviour 1:1, but the implementations are the source of truth.