diff --git a/README.md b/README.md
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--- a/README.md
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-swh-vault
-=========
-
-User-facing service that allows to retrieve parts of the archive as
-self-contained bundles.
-
-See the
-[documentation](https://docs.softwareheritage.org/devel/swh-vault/index.html)
-for more details.
diff --git a/docs/README.rst b/docs/README.rst
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+Software Heritage - Vault
+=========================
+
+User-facing service that allows to retrieve parts of the archive as
+self-contained bundles (e.g., individual releases, entire repository snapshots,
+etc.)
+The creation of a bundle is called "cooking" a bundle.
+
+
+Architecture
+------------
+
+The vault is made of two main parts:
+
+1. a stateful RPC server called the **backend**
+2. Celery tasks, called **cookers**
+
+.. _vault-backend:
+
+The Vault backend
+~~~~~~~~~~~~~~~~~
+
+The Vault backend is the RPC server other |swh| components (mainly
+:ref:`swh-web <swh-web>`) interact with.
+
+It is in charge of receiving cooking requests, scheduling corresponding tasks (via
+:ref:`swh-scheduler <swh-scheduler>` and Celery), getting heartbeats and final
+results from these, cooking tasks, and finally serving the results.
+
+It uses the same RPC protocol as the other component of the archive, and
+its interface is described in :mod:`swh.vault.interface`.
+
+.. _cookers:
+
+The cookers
+~~~~~~~~~~~
+
+Cookers are Python modules/classes, each in charge of cooking a type of bundle.
+The main ones are :mod:`swh.vault.cookers.directory` for flat tarballs of directories,
+and :mod:`swh.vault.cookers.git_bare` for bare ``.git`` repositories of any
+type of git object.
+They all derive from :class:`swh.vault.cookers.base.BaseVaultCooker`.
+
+The base cooker first notifies the backend the cooking task is in progress,
+then runs the cooker (which does the bundle-specific handling and uploads the result),
+then notifies the backend of the final result (success/failure).
+
+Cookers may notify the backend of the progress, so they can be displayed in
+swh-web's vault interface, which polls the status from the vault backend.
diff --git a/docs/index.rst b/docs/index.rst
--- a/docs/index.rst
+++ b/docs/index.rst
@@ -1,11 +1,6 @@
 .. _swh-vault:
 
-Software Heritage - Vault
-=========================
-
-User-facing service that allows to retrieve parts of the archive as
-self-contained bundles (e.g., individual releases, entire repository snapshots,
-etc.)
+.. include:: README.rst
 
 
 .. toctree::