diff --git a/cli/src/activation.rs b/cli/src/activation.rs
new file mode 100644
index 0000000..b99d6f1
--- /dev/null
+++ b/cli/src/activation.rs
@@ -0,0 +1,15 @@
+//! Activation and revert of plugin versions (PROTOCOL.md section 10.3).
+use crate::{Host, RpcResult, error};
+use serde_json::Value;
+
+impl Host {
+    /// `core.activate` and `core.revert`.
+    pub(crate) async fn activation(
+        &self,
+        _caller: &str,
+        _method: &str,
+        _params: Value,
+    ) -> RpcResult {
+        Err(error(-32601, "method not found"))
+    }
+}
diff --git a/cli/src/core.rs b/cli/src/core.rs
index 6539650..96d0810 100644
--- a/cli/src/core.rs
+++ b/cli/src/core.rs
@@ -49,6 +49,7 @@ impl Host {
                 Ok(Value::Null)
             }
             "log" => Ok(self.0.journal.query(p).await),
+            "activate" | "revert" => self.activation(caller, method, p).await,
             "exit" => {
                 self.0.exit.send_replace(true);
                 Ok(json!({}))
diff --git a/cli/src/graph.rs b/cli/src/graph.rs
new file mode 100644
index 0000000..7cf8f1d
--- /dev/null
+++ b/cli/src/graph.rs
@@ -0,0 +1,31 @@
+//! The interface graph (PROTOCOL.md section 10.4): the `rpc.discover`
+//! documents of all plugins, their imports, and the result of each check.
+//!
+//! The `/proc` layer reads the files of `/proc/core/` through these
+//! functions. They must be cheap and must not block: they return cached data.
+use crate::Host;
+use serde_json::Value;
+
+// The /proc layer (T6) uses these functions. Remove this when it does.
+#[allow(dead_code)]
+impl Host {
+    /// The content of `/proc/core/graph.json`.
+    pub(crate) fn graph_json(&self) -> Vec<u8> {
+        b"{}\n".to_vec()
+    }
+
+    /// The content of `/proc/core/graph.dot`.
+    pub(crate) fn graph_dot(&self) -> Vec<u8> {
+        b"digraph plugins {}\n".to_vec()
+    }
+
+    /// The plugins that have an `rpc.discover` document, for `/proc/core/plugins/`.
+    pub(crate) fn discovered_plugins(&self) -> Vec<String> {
+        Vec::new()
+    }
+
+    /// The `rpc.discover` document of the current `plugin.wasm` of `plugin`.
+    pub(crate) fn discover_document(&self, _plugin: &str) -> Option<Value> {
+        None
+    }
+}
diff --git a/cli/src/host.rs b/cli/src/host.rs
index 10edf61..6a9520a 100644
--- a/cli/src/host.rs
+++ b/cli/src/host.rs
@@ -65,23 +65,7 @@ impl Host {
             exit: watch::channel(false).0,
             components: components::Components::default(),
         }));
-        let boot: Vec<Value> = serde_json::from_slice(
-            &tokio::fs::read(host.0.world.root.join("config/boot.json")).await?,
-        )?;
-        for service in boot {
-            let result = host
-                .route(
-                    "core".into(),
-                    Some(json!(Uuid::now_v7().to_string())),
-                    service["method"].as_str().unwrap_or("").into(),
-                    service["params"].clone(),
-                    true,
-                )
-                .await;
-            if let Err(e) = result {
-                host.0.journal.write("core", "core", "core", &e.to_string());
-            }
-        }
+        host.boot().await?;
         Ok(host)
     }
     /// Register a native plugin for subsequent calls.
diff --git a/cli/src/lib.rs b/cli/src/lib.rs
index 4a4d4f5..2f78937 100644
--- a/cli/src/lib.rs
+++ b/cli/src/lib.rs
@@ -1,9 +1,11 @@
 //! A host for worlds of JSON-RPC plugins.
+mod activation;
 pub mod cargo;
 mod components;
 pub mod console;
 mod core;
 mod execution;
+mod graph;
 mod host;
 mod journal;
 mod locks;
@@ -11,6 +13,7 @@ mod native;
 mod process;
 mod routing;
 pub mod runtime;
+mod services;
 pub mod world;
 pub use host::Host;
 pub use native::{NativeContext, NativeFuture, NativePlugin};
diff --git a/cli/src/services.rs b/cli/src/services.rs
new file mode 100644
index 0000000..7faf67a
--- /dev/null
+++ b/cli/src/services.rs
@@ -0,0 +1,31 @@
+//! Services: the calls in `/config/boot.json` (PROTOCOL.md section 8). The
+//! core starts them in order at boot.
+use crate::Host;
+use serde_json::{Value, json};
+use uuid::Uuid;
+
+impl Host {
+    /// Start each service of `/config/boot.json` as a detached call with the
+    /// parent `core`, in order. A failure goes to the journal, and boot
+    /// continues.
+    pub(crate) async fn boot(&self) -> anyhow::Result<()> {
+        let boot: Vec<Value> = serde_json::from_slice(
+            &tokio::fs::read(self.0.world.root.join("config/boot.json")).await?,
+        )?;
+        for service in boot {
+            let result = self
+                .route(
+                    "core".into(),
+                    Some(json!(Uuid::now_v7().to_string())),
+                    service["method"].as_str().unwrap_or("").into(),
+                    service["params"].clone(),
+                    true,
+                )
+                .await;
+            if let Err(e) = result {
+                self.0.journal.write("core", "core", "core", &e.to_string());
+            }
+        }
+        Ok(())
+    }
+}