diff --git a/boilerplate/skeleton/extension/js/package.json b/boilerplate/skeleton/extension/js/package.json
index 1de7ee7..f709c63 100644
--- a/boilerplate/skeleton/extension/js/package.json
+++ b/boilerplate/skeleton/extension/js/package.json
@@ -7,15 +7,15 @@
   "dependencies": {
   },
   "devDependencies": {
-    "@flarum/jest-config": "^2.1.0",
+    "@flarum/jest-config": "^2.1.1",
     "@flarum/prettier-config": "^1.0.0",
     "flarum-tsconfig": "^2.0.0",
     "flarum-webpack-config": "^3.1.0",
-    "prettier": "^2.5.1",
+    "prettier": "^3.9.10",
     "typescript": "^5.9.3",
-    "typescript-coverage-report": "^0.6.1",
+    "typescript-coverage-report": "^0.6.4",
     "webpack": "^5.104.1",
-    "webpack-cli": "^4.9.1"
+    "webpack-cli": "^7.2.3"
   },
   "scripts": {
     "dev": "webpack --mode development --watch",
diff --git a/src/steps/upgrade/twopointoh/dependencies.ts b/src/steps/upgrade/twopointoh/dependencies.ts
index e81e59c..8f280f2 100644
--- a/src/steps/upgrade/twopointoh/dependencies.ts
+++ b/src/steps/upgrade/twopointoh/dependencies.ts
@@ -251,14 +251,16 @@ export default class Dependencies extends BaseUpgradeStep {
 
       // The versions a new extension is scaffolded with. 3.1.0 is the first
       // flarum-webpack-config that supplies TypeScript 5.9 and only asks for
-      // webpack as a peer, and @flarum/jest-config 2.1.0 tests with the mithril
-      // Flarum ships.
+      // webpack as a peer, and @flarum/jest-config 2.1.1 tests with the mithril
+      // Flarum ships and requires that flarum-webpack-config. Prettier 3 is what
+      // the upgrade has just formatted the code with.
       const map: Record<string, string> = {
         'flarum-webpack-config': '^3.1.0',
         'flarum-tsconfig': '^2.0.0',
-        '@flarum/jest-config': '^2.1.0',
+        '@flarum/jest-config': '^2.1.1',
+        prettier: '^3.9.10',
         webpack: '^5.104.1',
-        'webpack-cli': '^4.9.1',
+        'webpack-cli': '^7.2.3',
         // What Flarum builds and checks its typings with.
         typescript: '^5.9.3',
       };
diff --git a/test/steps/upgrade/dependencies.test.ts b/test/steps/upgrade/dependencies.test.ts
index d8b6cb8..42cad3e 100644
--- a/test/steps/upgrade/dependencies.test.ts
+++ b/test/steps/upgrade/dependencies.test.ts
@@ -136,10 +136,22 @@ describe('the dependencies step', () => {
       expect(pkg.devDependencies['flarum-webpack-config']).toBe('^3.1.0');
     });
 
-    it('requires @flarum/jest-config 2.1.0, which tests with the mithril Flarum ships', async () => {
+    it('requires @flarum/jest-config 2.1.1, which tests with the mithril Flarum ships and the flarum-webpack-config it builds with', async () => {
       const pkg = await upgrade('js/package.json', { devDependencies: { '@flarum/jest-config': '^2.0.0' } });
 
-      expect(pkg.devDependencies['@flarum/jest-config']).toBe('^2.1.0');
+      expect(pkg.devDependencies['@flarum/jest-config']).toBe('^2.1.1');
+    });
+
+    it('requires Prettier 3, which the upgrade formats the code with', async () => {
+      const pkg = await upgrade('js/package.json', onePackageJson);
+
+      expect(pkg.devDependencies.prettier).toBe('^3.9.10');
+    });
+
+    it('requires webpack-cli 7', async () => {
+      const pkg = await upgrade('js/package.json', onePackageJson);
+
+      expect(pkg.devDependencies['webpack-cli']).toBe('^7.2.3');
     });
 
     it('requires the webpack Flarum builds with', async () => {
@@ -150,13 +162,13 @@ describe('the dependencies step', () => {
 
     it('keeps tooling the extension already asks for newer versions of, and says so', async () => {
       const step = new Dependencies({} as any, '/extension', 1, 1, false);
-      const code = JSON.stringify({ devDependencies: { 'webpack-cli': '^5.1.4', webpack: '^5.65.0' } }, null, 2);
+      const code = JSON.stringify({ devDependencies: { 'webpack-cli': '^5.1.4', webpack: '^5.107.2' } }, null, 2);
       const result = await step.applyReplacements('js/package.json', code, step.advancedContent('js/package.json', code));
       const pkg = JSON.parse(result.updated as string);
 
-      expect(pkg.devDependencies['webpack-cli']).toBe('^5.1.4');
-      expect(pkg.devDependencies.webpack).toBe('^5.104.1');
-      expect(step.pauseMessage()).toContain('webpack-cli ^5.1.4');
+      expect(pkg.devDependencies.webpack).toBe('^5.107.2');
+      expect(pkg.devDependencies['webpack-cli']).toBe('^7.2.3');
+      expect(step.pauseMessage()).toContain('webpack ^5.107.2');
     });
 
     it('moves the build tooling to devDependencies, and says so', async () => {
@@ -194,12 +206,12 @@ describe('the dependencies step', () => {
 
     it('keeps the newer constraint of tooling listed under both keys', async () => {
       const pkg = await upgrade('js/package.json', {
-        dependencies: { 'flarum-webpack-config': '^2.0.0', prettier: '^3.0.3' },
-        devDependencies: { 'flarum-webpack-config': '^2.0.0', prettier: '^2.5.1' },
+        dependencies: { 'flarum-webpack-config': '^2.0.0', webpack: '^5.107.2' },
+        devDependencies: { 'flarum-webpack-config': '^2.0.0', webpack: '^5.65.0' },
       });
 
       expect(pkg.dependencies).toEqual({});
-      expect(pkg.devDependencies).toEqual({ 'flarum-webpack-config': '^3.1.0', prettier: '^3.0.3' });
+      expect(pkg.devDependencies).toEqual({ 'flarum-webpack-config': '^3.1.0', webpack: '^5.107.2' });
     });
 
     it('still drops a devDependency the extension also lists as a dependency, when it is not tooling', async () => {
@@ -220,7 +232,7 @@ describe('the dependencies step', () => {
 
     it('brings the tooling to the versions a new extension is scaffolded with', async () => {
       const scaffolded = scaffoldedPackageJson().devDependencies;
-      const tooling = ['flarum-webpack-config', 'flarum-tsconfig', '@flarum/jest-config', 'webpack', 'webpack-cli', 'typescript'];
+      const tooling = ['flarum-webpack-config', 'flarum-tsconfig', '@flarum/jest-config', 'prettier', 'webpack', 'webpack-cli', 'typescript'];
 
       const pkg = await upgrade('js/package.json', {
         devDependencies: Object.fromEntries(tooling.map((name) => [name, '^0.0.1'])),
@@ -275,9 +287,9 @@ describe('the dependencies step', () => {
     it('adds nothing to an extension that has them all', async () => {
       const scaffolded = scaffoldedPackageJson();
       const scripts = Object.fromEntries(typings.map((name) => [name, scaffolded.scripts[name]]));
-      const { pkg, notes } = await withTypings({ scripts, devDependencies: { prettier: '^2.5.1' } });
+      const { pkg, notes } = await withTypings({ scripts, devDependencies: { '@flarum/prettier-config': '^1.0.0' } });
 
-      expect(pkg.devDependencies).toEqual({ prettier: '^2.5.1' });
+      expect(pkg.devDependencies).toEqual({ '@flarum/prettier-config': '^1.0.0' });
       expect(notes).not.toContain('build and check typings');
     });
 
@@ -297,12 +309,14 @@ describe('the dependencies step', () => {
   });
 
   describe('a new extension', () => {
-    it('is scaffolded with flarum-webpack-config 3.1.0, @flarum/jest-config 2.1.0 and the webpack Flarum builds with', () => {
+    it('is scaffolded with the tooling Flarum builds with', () => {
       const scaffolded = scaffoldedPackageJson().devDependencies;
 
       expect(scaffolded['flarum-webpack-config']).toBe('^3.1.0');
-      expect(scaffolded['@flarum/jest-config']).toBe('^2.1.0');
+      expect(scaffolded['@flarum/jest-config']).toBe('^2.1.1');
       expect(scaffolded.webpack).toBe('^5.104.1');
+      expect(scaffolded['webpack-cli']).toBe('^7.2.3');
+      expect(scaffolded.prettier).toBe('^3.9.10');
     });
   });
 });