# Add analytics and other `` tags **Goal:** get a tracking script, a site-verification tag or a preconnect into every page's `` without changing anything else about the shell. **You need:** a `templates/` directory your Django project loads ahead of mdjango. This is the one template mdjango invites you to override; the rest of the [templates reference](../../reference/templates/) is a closed surface. Colours and type do **not** go here — they load through a setting, covered in [Change the colours and type](../change-colours-and-type/). ## 1. Shadow the head slot mdjango renders an empty component, `cotton/docs/head_extra.html`, at the end of every page's ``. Override it by creating a file at the same path inside a templates directory your project loads before mdjango: ```text your_project/ templates/ cotton/ docs/ head_extra.html # your version wins over mdjango's empty one ``` For Django to find yours first, that directory must be ahead of mdjango on the loader path — either an entry in `TEMPLATES[0]["DIRS"]` (searched before any app), or an app listed before `mdjango` in `INSTALLED_APPS` with `APP_DIRS` on. ## 2. Put your tags in it Whatever you write renders verbatim inside ``. A privacy-friendly analytics one-liner: ```django ``` Google Analytics 4 is two tags — an external loader and an inline bootstrap; both go in the slot together: ```django ``` The slot is not only for analytics. A verification `` or a `preconnect` works the same way: ```django ``` ## 3. Keep CSS in the setting, not the slot The two override channels do not overlap — use one each: - **Colours, type, the seven CSS seeds** → `MDJANGO_EXTRA_CSS`, a setting (see [Change the colours and type](../change-colours-and-type/)). - **Scripts and `` tags** → the head slot. `head_extra.html` is the *only* template mdjango supports overriding. Shadowing any other component — the header, the base document, the page — is unsupported: a project that needs different chrome (a logo, a footer, a different layout) has outgrown mdjango. ## 4. The export picks it up too If you [export a static site](../export-a-static-site/), `mdjango_build` renders through your project's own template loaders, so your `head_extra.html` lands in every exported page with no extra step. One constraint: the export does not rewrite URLs, so tags in the slot must use **absolute** URLs — as third-party snippets already do. A relative `src` would resolve against the page's own deep path and 404. ## What the slot cannot do for you - **A third-party script runs only where its host is reachable.** Opened from disk (a `file://` export with no server) or under a Content-Security-Policy that blocks the host, it silently does nothing and the page still renders. This is the trade-off for a tag mdjango does not ship — the external dependency is yours to accept. If your site sets a strict CSP, add the analytics host to it, the way the [production guide](../run-in-production/) notes you must already allow mdjango's own inline theme script. - **The slot is head-only.** It cannot add a footer, change the header, or alter the layout. That is by design: it renders inside ``, so it reaches nothing else.