diff --git a/JetStreamDriver.js b/JetStreamDriver.js
index e15905c7..7df47233 100644
--- a/JetStreamDriver.js
+++ b/JetStreamDriver.js
@@ -2257,7 +2257,7 @@ let BENCHMARKS = [
     new AsyncBenchmark({
         name: "jsdom-d3-startup",
         files: [
-            "./startup-helper/StartupBenchmark.js",
+            "./utils/StartupBenchmark.js",
             "./jsdom-d3-startup/benchmark.js",
         ],
         preload: {
@@ -2274,12 +2274,13 @@ let BENCHMARKS = [
     new AsyncBenchmark({
         name: "web-ssr",
         files: [
+            "./utils/StartupBenchmark.js",
             "./web-ssr/benchmark.js",
         ],
         preload: {
             // Debug Sources for nicer profiling.
-            // BUNDLE_BLOB: "./web-ssr/dist/bundle.js",
-            BUNDLE_BLOB: "./web-ssr/dist/bundle.min.js",
+            // BUNDLE: "./web-ssr/dist/bundle.js",
+            BUNDLE: "./web-ssr/dist/bundle.min.js",
         },
         tags: ["default", "js", "web", "ssr"],
         iterations: 30,
@@ -2876,7 +2877,7 @@ let BENCHMARKS = [
 
 
 const PRISM_JS_FILES = [
-    "./startup-helper/StartupBenchmark.js",
+    "./utils/StartupBenchmark.js",
     "./prismjs/benchmark.js",
 ];
 const PRISM_JS_PRELOADS = {
diff --git a/jsdom-d3-startup/webpack.config.mjs b/jsdom-d3-startup/webpack.config.mjs
index dcc833b4..579bb2ec 100644
--- a/jsdom-d3-startup/webpack.config.mjs
+++ b/jsdom-d3-startup/webpack.config.mjs
@@ -49,7 +49,7 @@ function createConfig({ filename, minify }) {
           use: {
             loader: "babel-loader",
             options: {
-              plugins: [ "../startup-helper/BabelCacheBuster.mjs" ],
+              plugins: [ "../utils/BabelCacheBuster.mjs" ],
             },
           },
         },
diff --git a/prismjs/webpack.config.mjs b/prismjs/webpack.config.mjs
index 57f375f1..404414ff 100644
--- a/prismjs/webpack.config.mjs
+++ b/prismjs/webpack.config.mjs
@@ -1,7 +1,7 @@
 import path from "path";
 import { fileURLToPath } from "url";
 import TerserPlugin from "terser-webpack-plugin";
-import CacheBusterCommentPlugin from "../startup-helper/BabelCacheBuster.mjs";
+import CacheBusterCommentPlugin from "../utils/BabelCacheBuster.mjs";
 import UnicodeEscapePlugin from "@dapplets/unicode-escape-webpack-plugin";
 import { LicenseWebpackPlugin } from "license-webpack-plugin";
 
diff --git a/tests/unit-tests.js b/tests/unit-tests.js
index 0bc0c78f..3d50ec42 100644
--- a/tests/unit-tests.js
+++ b/tests/unit-tests.js
@@ -23,7 +23,7 @@
 
 load("utils/shell-config.js");
 load("utils/params.js");
-load("startup-helper/StartupBenchmark.js");
+load("utils/StartupBenchmark.js");
 load("JetStreamDriver.js");
 
 function assertTrue(condition, message) {
diff --git a/startup-helper/BabelCacheBuster.mjs b/utils/BabelCacheBuster.mjs
similarity index 100%
rename from startup-helper/BabelCacheBuster.mjs
rename to utils/BabelCacheBuster.mjs
diff --git a/startup-helper/StartupBenchmark.js b/utils/StartupBenchmark.js
similarity index 94%
rename from startup-helper/StartupBenchmark.js
rename to utils/StartupBenchmark.js
index 9a1d6686..3f20b54f 100644
--- a/startup-helper/StartupBenchmark.js
+++ b/utils/StartupBenchmark.js
@@ -67,7 +67,14 @@ class StartupBenchmark {
   }
 
   async init() {
+    if (!JetStream.preload.BUNDLE) {
+      throw new Error("Missing JetStream.preload.BUNDLE");
+    }
     this.#sourceCode = await JetStream.getString(JetStream.preload.BUNDLE);
+    if (!this.sourceCode || !this.sourceCode.length) {
+      throw new Error("Couldn't load JetStream.preload.BUNDLE");
+    }
+
     const cacheCommentCount = this.sourceCode.match(
       CACHE_BUST_COMMENT_RE
     ).length;
diff --git a/web-ssr/benchmark.js b/web-ssr/benchmark.js
index 12f51ecd..cb88daa5 100644
--- a/web-ssr/benchmark.js
+++ b/web-ssr/benchmark.js
@@ -9,60 +9,25 @@ globalThis.console = {
 globalThis.clearTimeout = function () { };
 
 
-function quickHash(str) {
-  let hash = 5381;
-  let i = str.length;
-  while (i > 0) {
-    hash = (hash * 33) ^ (str.charCodeAt(i) | 0);
-    i-= 919;
-  }
-  return hash | 0;
-}
-
-const CACHE_BUST_COMMENT = "/*ThouShaltNotCache*/";
-const CACHE_BUST_COMMENT_RE = new RegExp(`\n${RegExp.escape(CACHE_BUST_COMMENT)}\n`, "g");
-
 // JetStream benchmark.
-class Benchmark {
+class Benchmark extends StartupBenchmark {
   // How many times (separate iterations) should we reuse the source code.
   // Use 0 to skip.
-  CODE_REUSE_COUNT = 1;
-  iterationCount = 0;
-  iteration = 0;
   lastResult = {};
-  sourceCode;
   sourceHash = 0
-  iterationSourceCodes = [];
-
-  constructor({ iterationCount }) {
-    this.iterationCount = iterationCount
-  }
-
-  async init() {
-    this.sourceCode = await JetStream.getString(JetStream.preload.BUNDLE_BLOB);
-    this.expect("Cache Comment Count", this.sourceCode.match(CACHE_BUST_COMMENT_RE).length, 597);
-    for (let i = 0; i < this.iterationCount; i++)
-      this.iterationSourceCodes[i] = this.prepareCode(i);
-  }
 
-  prepareCode(iteration) {
-    if (!this.CODE_REUSE_COUNT)
-      return this.sourceCode;
-    // Alter the code per iteration to prevent caching.
-    const cacheId = Math.floor(iteration / this.CODE_REUSE_COUNT);
-    const previousSourceCode = this.iterationSourceCodes[cacheId];
-    if (previousSourceCode)
-      return previousSourceCode
-    const sourceCode = this.sourceCode.replaceAll(CACHE_BUST_COMMENT_RE, `/*${cacheId}*/`);
-    // Ensure efficient string representation.
-    this.sourceHash = quickHash(sourceCode);
-    return sourceCode;
+  constructor({iterationCount}) {
+    super({
+      iterationCount,
+      expectedCacheCommentCount: 597,
+      sourceCodeReuseCount: 1,
+    });
   }
 
-  runIteration() {
-    let sourceCode = this.iterationSourceCodes[this.iteration];
+  runIteration(iteration) {
+    let sourceCode = this.iterationSourceCodes[iteration];
     if (!sourceCode)
-      throw new Error(`Could not find source for iteration ${this.iteration}`);
+      throw new Error(`Could not find source for iteration ${iteration}`);
     // Module in sourceCode it assigned to the ReactRenderTest variable.
     let ReactRenderTest;
 
@@ -71,16 +36,15 @@ class Benchmark {
     const runStart = performance.now();
 
     this.lastResult = ReactRenderTest.renderTest();
-    this.lastResult.htmlHash = quickHash(this.lastResult.html);
+    this.lastResult.htmlHash = this.quickHash(this.lastResult.html);
     const end = performance.now();
 
     const loadTime = runStart - initStart;
     const runTime = end - runStart;
     // For local debugging: 
-    // print(`Iteration ${this.iteration}:`);
+    // print(`Iteration ${iteration}:`);
     // print(`  Load time: ${loadTime.toFixed(2)}ms`);
     // print(`  Render time: ${runTime.toFixed(2)}ms`);
-    this.iteration++;
   }
 
   validate() {
diff --git a/web-ssr/webpack.config.mjs b/web-ssr/webpack.config.mjs
index f885c573..71633ecc 100644
--- a/web-ssr/webpack.config.mjs
+++ b/web-ssr/webpack.config.mjs
@@ -54,7 +54,7 @@ function createConfig({ filename, minify }) {
                 }],
                 "@babel/preset-react"
               ],
-              plugins: [path.resolve(__dirname, "../startup-helper/BabelCacheBuster.mjs")],
+              plugins: [path.resolve(__dirname, "../utils/BabelCacheBuster.mjs")],
             },
           },
         },
@@ -64,7 +64,7 @@ function createConfig({ filename, minify }) {
           use: {
             loader: "babel-loader",
             options: {
-              plugins: [path.resolve(__dirname, "../startup-helper/BabelCacheBuster.mjs")],
+              plugins: [path.resolve(__dirname, "../utils/BabelCacheBuster.mjs")],
             },
           },
         },