diff --git a/src/rebuild.ts b/src/rebuild.ts
index d12336c..13e5baf 100644
--- a/src/rebuild.ts
+++ b/src/rebuild.ts
@@ -91,21 +91,25 @@ export function planned(env: NodeJS.ProcessEnv = process.env): Build[] {
     builds.push({
       what: "installer",
       in: where["mesh-host"],
-      argv: ["make", "bootstrap", `IMAGE=${controlPlaneImage(env)}`, `BOOTSTRAP_OUT=${installer}`],
+      argv: ["make", "bootstrap", `IMAGE=${carriedImage(env)}`, `BOOTSTRAP_OUT=${installer}`],
     });
   }
   return builds;
 }
 
 /**
- * The control-plane image the installer carries.
+ * The image the installer carries.
  *
- * `mesh-control:development` is what mesh-control's `make image` tags, and what the scenarios name
- * — one tag, said in one place. It is overridable because a release installer carries a release
- * image, and nothing about that is the lab's business.
+ * **It is the builder, not the control plane** (novox/hq ADR 0073). The installer used to carry the
+ * thing it was going to run and now carries the thing that makes it, so a raised mesh holds a
+ * control plane it built from a repository and a commit rather than one it was handed.
+ *
+ * `mesh-builder:development` is what mesh-control's `make builder-image` tags — one tag, said in
+ * one place. Overridable because a release installer carries a release image, and nothing about
+ * that is the lab's business.
  */
-export function controlPlaneImage(env: NodeJS.ProcessEnv = process.env): string {
-  return env["MESH_LAB_CONTROL_IMAGE"] ?? "mesh-control:development";
+export function carriedImage(env: NodeJS.ProcessEnv = process.env): string {
+  return env["MESH_LAB_CARRIED_IMAGE"] ?? "mesh-builder:development";
 }
 
 /** rebuild runs the plan, and throws on the first failure rather than testing a stale artifact. */
diff --git a/test/integration/genesis-single.test.ts b/test/integration/genesis-single.test.ts
index 1221bb1..7d02ff1 100644
--- a/test/integration/genesis-single.test.ts
+++ b/test/integration/genesis-single.test.ts
@@ -34,6 +34,11 @@ const binary = hostBinaryPath();
 const installer = bootstrapBinaryPath();
 const bundle = process.env["MESH_LAB_BUNDLE"] ?? "";
 const catalogDir = process.env["MESH_LAB_CATALOG"] ?? "";
+// What the installer is told to build. It carries a builder rather than a finished control plane
+// (novox/hq ADR 0073), so genesis needs a repository and a commit — and a commit rather than a
+// branch, because what is cloned is the trust anchor for everything this mesh will ever run.
+const source = process.env["MESH_LAB_SOURCE"] ?? "";
+const sourceRef = process.env["MESH_LAB_SOURCE_REF"] ?? "";
 const KEEP = !!process.env["MESH_LAB_KEEP"];
 const FIXED_ID = process.env["MESH_LAB_INSTANCE_ID"] ?? (KEEP ? "genesis-single-live" : undefined);
 
@@ -41,7 +46,9 @@ const skip =
   !capability.usable ? capability.why :
   !binary ? "MESH_LAB_HOST_BINARY is not set to a built mesh-host" :
   !installer ? "MESH_LAB_BOOTSTRAP_BINARY is not set to a built mesh-bootstrap (mesh-host `make " +
-    "bootstrap IMAGE=mesh-control:development`)" :
+    "bootstrap IMAGE=mesh-builder:development`)" :
+  !source ? "MESH_LAB_SOURCE is not set to the repository the control plane is built from" :
+  !sourceRef ? "MESH_LAB_SOURCE_REF is not set to the commit to build" :
   !bundle || !existsSync(bundle) ? "MESH_LAB_BUNDLE is not set to a substrate template" :
   !catalogDir || !existsSync(catalogDir) ? "MESH_LAB_CATALOG is not set to mesh-catalog/modules" :
   false;
@@ -72,6 +79,8 @@ before(async () => {
       // naming a registry that does not exist — the installer overwrites it, and leaving it proves
       // that it does.
       bundleTemplate: substrateBundle(bundle, []),
+      source,
+      sourceRef,
       log: (m) => console.log(m),
     });
   } catch (err) {
diff --git a/test/integration/genesis.ts b/test/integration/genesis.ts
index 3cafb53..83b4a98 100644
--- a/test/integration/genesis.ts
+++ b/test/integration/genesis.ts
@@ -44,6 +44,15 @@ export interface GenesisOptions {
   catalogueOnMachine?: string;
   /** Where this mesh's own registry will answer. */
   registry?: string;
+  /**
+   * Where the control plane is built from, and the commit.
+   *
+   * The installer carries a builder rather than a finished control plane (novox/hq ADR 0073), so
+   * it has to be told what to make. A commit rather than a branch, because what genesis clones is
+   * the trust anchor for everything the mesh will ever run (ADR 0071).
+   */
+  source: string;
+  sourceRef: string;
   log?: (m: string) => void;
 }
 
@@ -84,6 +93,7 @@ export async function genesis(o: GenesisOptions): Promise<GenesisResult> {
   const name = await instanceNameOf(o.instanceId, node);
   const version = await placeBootstrap(name, node, o.installer, (m) => log(`genesis:${m}`));
   report.push(`  installer         ${version} at ${BOOTSTRAP_PATH}`);
+  report.push(`  builds from       ${o.source} at ${o.sourceRef.slice(0, 8)}`);
 
   // The catalogue. `mesh-bootstrap --catalog` reads manifests from a CHECKOUT on the machine,
   // because at this moment the mesh has no forge, no build machine and — until the registry step
@@ -102,6 +112,8 @@ export async function genesis(o: GenesisOptions): Promise<GenesisResult> {
 
   const command = [
     BOOTSTRAP_PATH,
+    `--source ${o.source}`,
+    `--source-ref ${o.sourceRef}`,
     `--bundle /tmp/substrate-template.lock`,
     `--catalog ${catalogueOnMachine}`,
     `--node ${node}`,
diff --git a/test/integration/whole-mesh-full.test.ts b/test/integration/whole-mesh-full.test.ts
index 875f521..c98e48c 100644
--- a/test/integration/whole-mesh-full.test.ts
+++ b/test/integration/whole-mesh-full.test.ts
@@ -73,6 +73,11 @@ const binary = hostBinaryPath();
 const installer = bootstrapBinaryPath();
 const bundle = process.env["MESH_LAB_BUNDLE"] ?? "";
 const modulesEnv = process.env["MESH_LAB_MODULES"] ?? "";
+// What the installer is told to build. It carries a builder rather than a finished control plane
+// (novox/hq ADR 0073), so genesis is given a repository and a commit — and a commit rather than a
+// branch, because what is cloned is the trust anchor for everything this mesh will ever run.
+const source = process.env["MESH_LAB_SOURCE"] ?? "";
+const sourceRef = process.env["MESH_LAB_SOURCE_REF"] ?? "";
 
 const skip = !capability.usable
   ? `lab not usable: ${capability.why}`
@@ -82,9 +87,13 @@ const skip = !capability.usable
       ? "MESH_LAB_BUNDLE is not set to a substrate bundle (mesh-host examples/)"
       : !installer || !existsSync(installer)
         ? "MESH_LAB_BOOTSTRAP_BINARY is not set to a built mesh-bootstrap (mesh-host `make " +
-          "bootstrap IMAGE=mesh-control:development`). The anchor is raised BY the installer now, " +
+          "bootstrap IMAGE=mesh-builder:development`). The anchor is raised BY the installer now, " +
           "so a run without one would be testing the procedure this bed exists to stop testing"
-        : false;
+        : !source
+          ? "MESH_LAB_SOURCE is not set to the repository the control plane is built from"
+          : !sourceRef
+            ? "MESH_LAB_SOURCE_REF is not set to the commit to build"
+            : false;
 
 const SCENARIO = "whole-mesh-full";
 /** novox hosts the substrate and the control plane; it is where `mesh` commands run. */
@@ -526,6 +535,7 @@ async function genesis(images: HeldImage[]): Promise<GenesisResult> {
   const version = await placeBootstrap(name, CONTROL, installer as string,
     (m) => console.log(`genesis:${m}`));
   report.push(`  installer         ${version} at ${BOOTSTRAP_PATH}`);
+  report.push(`  builds from       ${source} at ${sourceRef.slice(0, 8)}`);
 
   // The catalogue. `mesh-bootstrap --catalog` reads manifests from a CHECKOUT on the machine,
   // because at this moment the mesh has no forge, no build machine and — until step 7 finishes —
@@ -560,6 +570,8 @@ async function genesis(images: HeldImage[]): Promise<GenesisResult> {
 
   const command = [
     BOOTSTRAP_PATH,
+    `--source ${source}`,
+    `--source-ref ${sourceRef}`,
     `--bundle /tmp/substrate-template.lock`,
     `--catalog ${CATALOGUE_ON_MACHINE}`,
     `--node ${CONTROL}`,
diff --git a/test/rebuild.test.ts b/test/rebuild.test.ts
index d8b04e3..f452700 100644
--- a/test/rebuild.test.ts
+++ b/test/rebuild.test.ts
@@ -1,6 +1,6 @@
 import { test } from "node:test";
 import assert from "node:assert/strict";
-import { planned, controlPlaneImage } from "../src/rebuild.ts";
+import { planned, carriedImage } from "../src/rebuild.ts";
 import { repositories } from "../src/repos.ts";
 import { loadScenario } from "../src/declaration/parse.ts";
 
@@ -61,7 +61,7 @@ test("the installer is built, carrying the image built in the same run", () => {
 
   const installer = builds.find((b) => b.what === "installer")!;
   assert.equal(installer.in, "/repo/host");
-  assert.ok(installer.argv.includes(`IMAGE=${controlPlaneImage({})}`), installer.argv.join(" "));
+  assert.ok(installer.argv.includes(`IMAGE=${carriedImage({})}`), installer.argv.join(" "));
   assert.ok(installer.argv.includes("BOOTSTRAP_OUT=/repo/host/mesh-bootstrap"), installer.argv.join(" "));
 });