diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index c82a1c13c0..efdfad31d1 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -37,10 +37,12 @@ To get started clone the repo and get the web application started.
 1.  Run `git clone git@github.com:firefox-devtools/profiler.git`
 2.  Run `cd profiler`
 3.  Run `yarn install`, this will install all of the dependencies.
-4.  Run `yarn start`, this will start up the development server.
+4.  Run `yarn start` to serve a production build with live rebuilds and no service worker.
 5.  Point your browser to [http://localhost:4242](http://localhost:4242).
 6.  If port `4242` is taken, then you can run the web app on a different port: `FX_PROFILER_PORT=1234 yarn start`
 
+Use `yarn start-dev` for an unminified development build with React diagnostics on port `4241`. Use `yarn start-prod` to build and serve the deployable version, including its service worker, on port `4243`.
+
 This project uses [TypeScript](https://www.typescriptlang.org/).
 
 ## Using GitHub Codespaces
diff --git a/package.json b/package.json
index 96d95bbd57..c56d8bf82e 100644
--- a/package.json
+++ b/package.json
@@ -40,7 +40,8 @@
     "preinstall": "node bin/pre-install.js",
     "publish": "rimraf public_html && cp -r dist public_html",
     "serve-static": "ws -d dist/ -s index.html -p 4243",
-    "start": "cross-env NODE_ENV=development node scripts/run-dev-server.mjs",
+    "start": "cross-env NODE_ENV=production ENABLE_SERVICE_WORKER=false node scripts/run-dev-server.mjs",
+    "start-dev": "cross-env NODE_ENV=development node scripts/run-dev-server.mjs",
     "start-prod": "yarn build-prod && yarn serve-static",
     "start-l10n": "cross-env NODE_ENV=development L10N=1 node scripts/run-dev-server.mjs",
     "start-l10n-prod": "yarn build-l10n-prod && yarn serve-static",
diff --git a/scripts/build.mjs b/scripts/build.mjs
index 01ebca600d..b6650d147a 100644
--- a/scripts/build.mjs
+++ b/scripts/build.mjs
@@ -15,7 +15,11 @@ async function build() {
 
   // Build the worker first so we can read its output path from the metafile
   // and inject it into the main bundle via SOURCE_MAP_WORKER_PATH.
-  const workerResult = await esbuild.build(sourceMapWorkerConfig);
+  const workerResult = await esbuild.build({
+    ...sourceMapWorkerConfig,
+    entryNames:
+      process.env.NODE_ENV === 'production' ? '[name]-[hash]' : '[name]',
+  });
 
   const buildResult = await esbuild.build({
     ...mainBundleConfig,
diff --git a/scripts/lib/esbuild-configs.mjs b/scripts/lib/esbuild-configs.mjs
index 9da953801b..227a4e3aad 100644
--- a/scripts/lib/esbuild-configs.mjs
+++ b/scripts/lib/esbuild-configs.mjs
@@ -84,6 +84,9 @@ export const mainBundleConfig = {
     // In dev, the worker is not hashed so the path is predictable.
     // In production, build.mjs overrides this after building the worker first.
     SOURCE_MAP_WORKER_PATH: JSON.stringify('/source-map.worker.js'),
+    'process.env.ENABLE_SERVICE_WORKER': JSON.stringify(
+      process.env.ENABLE_SERVICE_WORKER || 'true'
+    ),
   },
   external: ['zlib'],
   plugins: [
@@ -118,10 +121,10 @@ export const mainBundleConfig = {
 // Source map worker bundle configuration.
 // Built as a standalone IIFE so that npm dependencies (lezer, source-map) are
 // bundled into a single file that can be loaded as a Web Worker without needing
-// ES module support. In production the output filename includes a content hash
-// (e.g. source-map-ABCD1234.worker.js). The path is then injected into the main
-// bundle via the SOURCE_MAP_WORKER_PATH define. In dev there is no hash since the
-// dev server always serves fresh content and the define can't be updated mid-watch.
+// ES module support. Watched builds use a stable filename because the main
+// bundle's SOURCE_MAP_WORKER_PATH define can't be updated when only the worker
+// changes. The one-off production build overrides this with a content hash and
+// injects the resulting path into the main bundle.
 export const sourceMapWorkerConfig = {
   ...baseConfig,
   entryPoints: ['src/profile-logic/source-maps/source-map.worker.ts'],
@@ -131,7 +134,7 @@ export const sourceMapWorkerConfig = {
   target: browserslistToEsbuild(),
   sourcemap: true,
   splitting: false,
-  entryNames: isProduction ? '[name]-[hash]' : '[name]',
+  entryNames: '[name]',
   metafile: true,
   plugins: [wasmLoader()],
 };
diff --git a/scripts/run-dev-server.mjs b/scripts/run-dev-server.mjs
index 71d87fef02..2aaa4052cd 100644
--- a/scripts/run-dev-server.mjs
+++ b/scripts/run-dev-server.mjs
@@ -11,7 +11,9 @@ import { serveAndOpenProfile } from './lib/profile-server.mjs';
 import yargs from 'yargs';
 import { hideBin } from 'yargs/helpers';
 
-const port = parseInt(process.env.FX_PROFILER_PORT) || 4242;
+const isProduction = process.env.NODE_ENV === 'production';
+const defaultPort = isProduction ? 4242 : 4241;
+const port = parseInt(process.env.FX_PROFILER_PORT) || defaultPort;
 const host = process.env.FX_PROFILER_HOST || 'localhost';
 
 const argv = yargs(hideBin(process.argv))
@@ -33,13 +35,15 @@ startDevServer(mainBundleConfig, {
     console.log(barAscii);
     console.log(`> Firefox Profiler is listening at: ${profilerUrl}\n`);
 
-    if (port === 4242) {
+    if (port === defaultPort) {
       console.log(
         '> You can change this default port with the environment variable FX_PROFILER_PORT.\n'
       );
     }
 
-    console.log('> esbuild development server enabled');
+    console.log(
+      `> esbuild ${isProduction ? 'production' : 'development'} build with live rebuilds enabled`
+    );
     console.log(barAscii);
 
     if (argv.profile) {
diff --git a/src/components/app/ServiceWorkerManager.tsx b/src/components/app/ServiceWorkerManager.tsx
index db4d87ec73..bca9c6ff27 100644
--- a/src/components/app/ServiceWorkerManager.tsx
+++ b/src/components/app/ServiceWorkerManager.tsx
@@ -244,6 +244,7 @@ class ServiceWorkerManagerImpl extends PureComponent<Props, State> {
   override componentDidMount() {
     if (
       process.env.NODE_ENV === 'production' &&
+      process.env.ENABLE_SERVICE_WORKER !== 'false' &&
       // Do not install the service worker for l10n branch so localizers can see
       // the changes easily with a single refresh. This variable is added by
       // esbuild's define option.
diff --git a/src/test/components/ServiceWorkerManager.test.tsx b/src/test/components/ServiceWorkerManager.test.tsx
index 138dc974bd..f11daad2f4 100644
--- a/src/test/components/ServiceWorkerManager.test.tsx
+++ b/src/test/components/ServiceWorkerManager.test.tsx
@@ -61,6 +61,7 @@ describe('app/ServiceWorkerManager', () => {
 
   afterEach(() => {
     process.env.NODE_ENV = 'development';
+    delete process.env.ENABLE_SERVICE_WORKER;
 
     Object.defineProperty(window, 'location', nativeLocation);
     nativeLocation = null;
@@ -171,6 +172,14 @@ describe('app/ServiceWorkerManager', () => {
     expect(Workbox).not.toHaveBeenCalled();
   });
 
+  it('does not register a service worker in a local production build', () => {
+    process.env.NODE_ENV = 'production';
+    process.env.ENABLE_SERVICE_WORKER = 'false';
+
+    setup();
+    expect(Workbox).not.toHaveBeenCalled();
+  });
+
   describe('in the home, with the `none` datasource', () => {
     it('shows a notice when the SW is updated, and the user can close it', () => {
       process.env.NODE_ENV = 'production';