diff --git a/patches/@endo+compartment-mapper+1.1.0.patch b/patches/@endo+compartment-mapper+1.1.0.patch
new file mode 100644
index 0000000000..709d8aefde
--- /dev/null
+++ b/patches/@endo+compartment-mapper+1.1.0.patch
@@ -0,0 +1,105 @@
+diff --git a/node_modules/@endo/compartment-mapper/index.js b/node_modules/@endo/compartment-mapper/index.js
+index acccf2c..8b0333e 100644
+--- a/node_modules/@endo/compartment-mapper/index.js
++++ b/node_modules/@endo/compartment-mapper/index.js
+@@ -6,6 +6,8 @@ export {
+   writeArchive,
+   mapLocation,
+   hashLocation,
++  loadCompartmentForArchive,
++  makeArchiveCompartmentMap,
+ } from './src/archive.js';
+ export {
+   parseArchive,
+diff --git a/node_modules/@endo/compartment-mapper/src/archive.js b/node_modules/@endo/compartment-mapper/src/archive.js
+index 17f10f7..686fc95 100644
+--- a/node_modules/@endo/compartment-mapper/src/archive.js
++++ b/node_modules/@endo/compartment-mapper/src/archive.js
+@@ -289,15 +289,18 @@ export const makeArchiveCompartmentMap = (compartmentMap, sources) => {
+  * @param {ReadFn | ReadPowers} powers
+  * @param {string} moduleLocation
+  * @param {ArchiveOptions} [options]
+- * @returns {Promise<{sources: Sources, compartmentMapBytes: Uint8Array, sha512?: string}>}
++ * @returns {Promise<import('./types.js').LoadCompartmentForArchiveResult>}
+  */
+-const digestLocation = async (powers, moduleLocation, options) => {
++export const loadCompartmentForArchive = async (
++  powers,
++  moduleLocation,
++  options,
++) => {
+   const {
+     moduleTransforms,
+     modules: exitModules = {},
+     dev = false,
+     tags = new Set(),
+-    captureSourceLocation = undefined,
+     searchSuffixes = undefined,
+     commonDependencies = undefined,
+     importHook: exitModuleImportHook = undefined,
+@@ -334,6 +337,8 @@ const digestLocation = async (powers, moduleLocation, options) => {
+     entry: { module: entryModuleSpecifier, compartment: entryCompartmentName },
+   } = compartmentMap;
+ 
++  // compartment map contains no source code
++
+   /** @type {Sources} */
+   const sources = Object.create(null);
+ 
+@@ -361,7 +366,25 @@ const digestLocation = async (powers, moduleLocation, options) => {
+     parserForLanguage,
+     archiveOnly: true,
+   });
++
+   await compartment.load(entryModuleSpecifier);
++
++  return { attenuatorsCompartment, compartmentMap, sources, computeSha512 };
++};
++
++/**
++ * @param {ReadFn | ReadPowers} powers
++ * @param {string} moduleLocation
++ * @param {ArchiveOptions} [options]
++ * @returns {Promise<{sources: Sources, compartmentMapBytes: Uint8Array, sha512?: string}>}
++ */
++const digestLocation = async (powers, moduleLocation, options) => {
++  const { captureSourceLocation = undefined, policy = undefined } =
++    options || {};
++
++  const { attenuatorsCompartment, compartmentMap, sources, computeSha512 } =
++    await loadCompartmentForArchive(powers, moduleLocation, options);
++
+   if (policy) {
+     // retain all attenuators.
+     await Promise.all(
+diff --git a/node_modules/@endo/compartment-mapper/src/types.js b/node_modules/@endo/compartment-mapper/src/types.js
+index 9e8f605..f760124 100644
+--- a/node_modules/@endo/compartment-mapper/src/types.js
++++ b/node_modules/@endo/compartment-mapper/src/types.js
+@@ -504,3 +504,13 @@ export {};
+  * Any object. All objects. Not `null`, though.
+  * @typedef {Record<PropertyKey, any>} SomeObject
+  */
++
++/**
++ * Return value of `loadCompartmentForArchive`.
++ *
++ * @typedef LoadCompartmentForArchiveResult
++ * @property {CompartmentMapDescriptor} compartmentMap
++ * @property {Sources} sources
++ * @property {Compartment} attenuatorsCompartment
++ * @property {(bytes: Uint8Array) => string} [computeSha512]
++ */
+diff --git a/node_modules/@endo/compartment-mapper/types.d.ts b/node_modules/@endo/compartment-mapper/types.d.ts
+index e480609..9b011ae 100644
+--- a/node_modules/@endo/compartment-mapper/types.d.ts
++++ b/node_modules/@endo/compartment-mapper/types.d.ts
+@@ -5,6 +5,8 @@ export {
+   writeArchive,
+   mapLocation,
+   hashLocation,
++  loadCompartmentForArchive,
++  makeArchiveCompartmentMap,
+ } from './src/archive.js';
+ export {
+   parseArchive,