diff --git a/packages/daemon/src/daemon.js b/packages/daemon/src/daemon.js
index 96bdd71e18..334710f031 100644
--- a/packages/daemon/src/daemon.js
+++ b/packages/daemon/src/daemon.js
@@ -373,17 +373,13 @@ const makeDaemonCore = async (
         context,
       );
     } else if (formula.type === 'guest') {
-      const storeFormulaNumber = derive(formulaNumber, 'pet-store');
-      const storeFormulaIdentifier = `pet-store:${storeFormulaNumber}`;
-      const workerFormulaNumber = derive(formulaNumber, 'worker');
-      const workerFormulaIdentifier = `worker:${workerFormulaNumber}`;
       // Behold, recursion:
       // eslint-disable-next-line no-use-before-define
       return makeIdentifiedGuestController(
         formulaIdentifier,
         formula.host,
-        storeFormulaIdentifier,
-        workerFormulaIdentifier,
+        formula.petStore,
+        formula.worker,
         context,
       );
     } else if (formula.type === 'web-bundle') {
@@ -705,6 +701,20 @@ const makeDaemonCore = async (
     );
   };
 
+  /**
+   * @returns {Promise<{ formulaIdentifier: string, value: import('./types').EndoWorker }>}
+   */
+  const incarnateWorker = async () => {
+    const formulaNumber = await randomHex512();
+    /** @type {import('./types.js').WorkerFormula} */
+    const formula = {
+      type: 'worker',
+    };
+    return /** @type {Promise<{ formulaIdentifier: string, value: import('./types').EndoWorker }>} */ (
+      provideValueForNumberedFormula(formula.type, formulaNumber, formula)
+    );
+  };
+
   /**
    * @param {string} endoFormulaIdentifier
    * @param {string} leastAuthorityFormulaIdentifier
@@ -717,8 +727,11 @@ const makeDaemonCore = async (
     specifiedWorkerFormulaIdentifier,
   ) => {
     const formulaNumber = await randomHex512();
-    const workerFormulaIdentifier =
-      specifiedWorkerFormulaIdentifier || `worker:${await randomHex512()}`;
+    let workerFormulaIdentifier = specifiedWorkerFormulaIdentifier;
+    if (workerFormulaIdentifier === undefined) {
+      ({ formulaIdentifier: workerFormulaIdentifier } =
+        await incarnateWorker());
+    }
     const inspectorFormulaNumber = derive(formulaNumber, 'pet-inspector');
     const inspectorFormulaIdentifier = `pet-inspector:${inspectorFormulaNumber}`;
     // Note the pet store formula number derivation path:
@@ -745,10 +758,16 @@ const makeDaemonCore = async (
    */
   const incarnateGuest = async hostHandleFormulaIdentifier => {
     const formulaNumber = await randomHex512();
+    const storeFormulaNumber = derive(formulaNumber, 'pet-store');
+    const storeFormulaIdentifier = `pet-store:${storeFormulaNumber}`;
+    const { formulaIdentifier: workerFormulaIdentifier } =
+      await incarnateWorker();
     /** @type {import('./types.js').GuestFormula} */
     const formula = {
       type: 'guest',
       host: hostHandleFormulaIdentifier,
+      petStore: storeFormulaIdentifier,
+      worker: workerFormulaIdentifier,
     };
     return /** @type {Promise<{ formulaIdentifier: string, value: import('./types').EndoGuest }>} */ (
       provideValueForNumberedFormula(formula.type, formulaNumber, formula)
@@ -890,8 +909,9 @@ const makeDaemonCore = async (
   const incarnateEndoBootstrap = async specifiedFormulaNumber => {
     const formulaNumber = specifiedFormulaNumber || (await randomHex512());
     const endoFormulaIdentifier = `endo:${formulaNumber}`;
-    const defaultHostWorkerFormulaIdentifier = `worker:${await randomHex512()}`;
 
+    const { formulaIdentifier: defaultHostWorkerFormulaIdentifier } =
+      await incarnateWorker();
     const { formulaIdentifier: leastAuthorityFormulaIdentifier } =
       await incarnateLeastAuthority();
 
@@ -927,6 +947,7 @@ const makeDaemonCore = async (
   const makeIdentifiedHost = makeHostMaker({
     provideValueForFormulaIdentifier,
     provideControllerForFormulaIdentifier,
+    incarnateWorker,
     incarnateHost,
     incarnateGuest,
     incarnateEval,
diff --git a/packages/daemon/src/host.js b/packages/daemon/src/host.js
index e72b58107e..00d6a61f27 100644
--- a/packages/daemon/src/host.js
+++ b/packages/daemon/src/host.js
@@ -8,6 +8,7 @@ const { quote: q } = assert;
 export const makeHostMaker = ({
   provideValueForFormulaIdentifier,
   provideControllerForFormulaIdentifier,
+  incarnateWorker,
   incarnateHost,
   incarnateGuest,
   incarnateEval,
@@ -207,14 +208,15 @@ export const makeHostMaker = ({
       if (workerName === 'MAIN') {
         return mainWorkerFormulaIdentifier;
       } else if (workerName === 'NEW') {
-        const workerId512 = await randomHex512();
-        return `worker:${workerId512}`;
+        const { formulaIdentifier: workerFormulaIdentifier } =
+          await incarnateWorker();
+        return workerFormulaIdentifier;
       }
       assertPetName(workerName);
       let workerFormulaIdentifier = identifyLocal(workerName);
       if (workerFormulaIdentifier === undefined) {
-        const workerId512 = await randomHex512();
-        workerFormulaIdentifier = `worker:${workerId512}`;
+        ({ formulaIdentifier: workerFormulaIdentifier } =
+          await incarnateWorker());
         assertPetName(workerName);
         await petStore.write(workerName, workerFormulaIdentifier);
       }
diff --git a/packages/daemon/src/types.d.ts b/packages/daemon/src/types.d.ts
index 1f632b7974..8c452d42d9 100644
--- a/packages/daemon/src/types.d.ts
+++ b/packages/daemon/src/types.d.ts
@@ -64,6 +64,10 @@ type EndoFormula = {
   webPageJs?: string;
 };
 
+type WorkerFormula = {
+  type: 'worker';
+};
+
 type HostFormula = {
   type: 'host';
   worker: string;
@@ -76,6 +80,8 @@ type HostFormula = {
 type GuestFormula = {
   type: 'guest';
   host: string;
+  petStore: string;
+  worker: string;
 };
 
 type LeastAuthorityFormula = {
@@ -140,6 +146,7 @@ type HandleFormula = {
 
 export type Formula =
   | EndoFormula
+  | WorkerFormula
   | HostFormula
   | GuestFormula
   | LeastAuthorityFormula