Component Map

Which template renders the Hero block? What breaks if I change _components/button.twig? Which pages do I check before I open a pull request?

In a Craft project the answer is spread over Twig includes, a dispatcher that picks a template by block.type.handle, the content model in the control panel, and the entries that use each block. Component Map puts it together, from the command line:

php craft component-map/impact --since=main

tells you which blocks and pages your branch affects — and lists the entries to open in the browser, with their URLs.

What it knows

Every template reference, read with Twig's own lexer: include, embed, extends, import, from, use, include(), source() — including dynamic ones like '_adapters/' ~ block.type.handle ~ '.twig'.
The content model: sections and their templates, entry types, Matrix fields and the blocks they allow.
The link between them. A Hero block is rendered by _adapters/hero.twig, via your dispatcher — so the map knows which blocks a component change affects, not just which files include it.
Where each block is used, at any depth of nesting — a Card inside a Cards Grid on a page.

Commands

component-map/show <template|block|section> — where it is used, what it uses, which entries it is on.
component-map/impact <files> | --git | --since=main — what a change affects: templates, blocks, pages, and the entries to check. Changes to project config (entry types, Matrix fields, sections) count too; deleted templates count through whatever still references them.
component-map/build --stdout — the whole map as Markdown.
component-map/agents --file=AGENTS.md — tells your coding agent (Claude Code, Cursor, Codex…) to check the map before and after it edits a template.

Every command also speaks --json.

For local development

Component Map runs where you and your coding agent edit templates. It is read-only and console-only: nothing is generated into your repository, nothing is exposed over HTTP. The map is built from your templates as they are, on every call — there is nothing to keep up to date.

Works on its own; if you also use Component Check, impact tells it which blocks to test.