diff --git a/README.md b/README.md
index bde28f40..a00ae9c5 100644
--- a/README.md
+++ b/README.md
@@ -53,6 +53,9 @@ sources from master branch with `openaddr-enqueue-sources`:
 Development
 -----------
 
+[Documentation for machine internals](docs/README.md) can help point you in the
+right direction for development.
+
 Test the OpenAddresses machine with `test.py`:
 
     python test.py
diff --git a/docs/README.md b/docs/README.md
new file mode 100644
index 00000000..9de0bb18
--- /dev/null
+++ b/docs/README.md
@@ -0,0 +1,18 @@
+Machine Internals
+=================
+
+This documentation is current as-of [Machine 2.1.8](https://github.com/openaddresses/machine/releases/tag/2.1.8).
+
+*   **[Components](components.md)**
+    
+    Basic moving parts including web application, worker pool, and scheduled
+    tasks.
+    
+*   **[Persistent Data](persistence.md)**
+    
+    Locations where we store data.
+    
+*   **[Processes](processes.md)**
+    
+    Periodic and event-driven processes paths through components and persistent
+    data stores.
diff --git a/docs/components.md b/docs/components.md
index df002880..91eac97a 100644
--- a/docs/components.md
+++ b/docs/components.md
@@ -1,6 +1,8 @@
 Components
 ==========
 
+Basic moving parts including web application, worker pool, and scheduled tasks.
+
 <a name="webhook">Webhook</a>
 -------
 
diff --git a/docs/persistence.md b/docs/persistence.md
index bb9d9b85..1762d840 100644
--- a/docs/persistence.md
+++ b/docs/persistence.md
@@ -1,7 +1,7 @@
 Persistent Data
 ===============
 
-We store persistent data in two locations: a PostgreSQL database and Amazon S3.
+Locations where we store data.
 
 <a name="db">Database</a>
 --------
diff --git a/docs/processes.md b/docs/processes.md
index 2196b76e..0dd6dff5 100644
--- a/docs/processes.md
+++ b/docs/processes.md
@@ -1,6 +1,8 @@
 Processes
 =========
 
+Periodic and event-driven processes paths through components and persistent data stores.
+
 <a name="set">Batch Set</a>
 ---------