diff --git a/packages/deploy-script-support/src/writeCoreEvalParts.js b/packages/deploy-script-support/src/writeCoreEvalParts.js
index ddcb32e5009..2282a3a86ec 100644
--- a/packages/deploy-script-support/src/writeCoreEvalParts.js
+++ b/packages/deploy-script-support/src/writeCoreEvalParts.js
@@ -4,6 +4,7 @@ import { E } from '@endo/far';
 
 import { createBundles } from '@agoric/internal/src/node/createBundles.js';
 import { deeplyFulfilledObject } from '@agoric/internal';
+import path from 'node:path';
 import { defangAndTrim, mergePermits, stringify } from './code-gen.js';
 import {
   makeCoreProposalBehavior,
@@ -14,6 +15,7 @@ import {
  * @import {CoreEvalDescriptor} from './externalTypes.js';
  */
 
+// TODO consider using dots instead of dashes  distinguish the module shape qualifierfrom the identifier. (e.g. `-plan.json' to `.plan.json`)
 /**
  * @typedef CoreEvalPlan
  * @property {string} name
@@ -26,7 +28,7 @@ import {
  * @callback WriteCoreEval write to disk the files needed for a CoreEval (js code to`${filePrefix}.js`, permits to `${filePrefix}-permit.json`, an overall
  *   summary to `${filePrefix}-plan.json), plus whatever bundles bundles the code loads)
  * see CoreEval in {@link '/golang/cosmos/x/swingset/types/swingset.pb.go'}
- * @param {string} filePrefix name on disk
+ * @param {string} evalName name on disk
  * @param {import('./externalTypes.js').CoreEvalBuilder} builder
  * @returns {Promise<CoreEvalPlan>}
  */
@@ -100,7 +102,7 @@ export const makeWriteCoreEval = (
       Promise.resolve()
     );
   /** @type {WriteCoreEval} */
-  const writeCoreEval = async (filePrefix, builder) => {
+  const writeCoreEval = async (evalName, builder, scriptModule) => {
     /**
      *
      * @param {string} entrypoint
@@ -132,7 +134,7 @@ export const makeWriteCoreEval = (
 
       // Serialise the installations.
       mutex = E.when(mutex, async () => {
-        // console.log('installing', { filePrefix, entrypoint, bundlePath });
+        // console.log('installing', { evalName, entrypoint, bundlePath });
         const spec = await getBundleSpec(bundle, getBundler, opts);
         bundles.push({
           entrypoint,
@@ -161,7 +163,7 @@ export const makeWriteCoreEval = (
       harden(builder({ publishRef, install })),
     );
     const { sourceSpec, getManifestCall } = evalDescriptor;
-    // console.log('created', { filePrefix, sourceSpec, getManifestCall });
+    // console.log('created', { evalName, sourceSpec, getManifestCall });
 
     // Extract the top-level permit.
     const { permits: evalPermits, manifest: customManifest } =
@@ -170,7 +172,7 @@ export const makeWriteCoreEval = (
     // Get an install
     const manifestBundleRef = await publishRef(install(sourceSpec));
 
-    // console.log('writing', { filePrefix, manifestBundleRef, sourceSpec });
+    // console.log('writing', { evalName, manifestBundleRef, sourceSpec });
     const code = `\
 // This is generated by writeCoreEval; please edit!
 /* eslint-disable */
@@ -189,24 +191,29 @@ behavior;
 
     const trimmed = defangAndTrim(code);
 
-    const permitFile = `${filePrefix}-permit.json`;
+    // If the scriptModule is present, include it in the name of the plan
+    const planName = scriptModule
+      ? `${path.basename(scriptModule, '.js')}-${evalName}`
+      : evalName;
+
+    const permitFile = `${planName}-permit.json`;
     log(`creating ${permitFile}`);
     await writeFile(permitFile, JSON.stringify(evalPermits, null, 2));
 
-    const codeFile = `${filePrefix}.js`;
+    const codeFile = `${planName}.js`;
     log(`creating ${codeFile}`);
     await writeFile(codeFile, trimmed);
 
     /** @type {CoreEvalPlan} */
     const plan = {
-      name: filePrefix,
+      name: planName,
       script: codeFile,
       permit: permitFile,
       bundles,
     };
 
     await writeFile(
-      `${filePrefix}-plan.json`,
+      `${planName}-plan.json`,
       `${JSON.stringify(plan, null, 2)}\n`,
     );