From 5babb235faa79f2592092d43992285ecdf9f2a3a Mon Sep 17 00:00:00 2001
From: lizschwab <liz.schwab@raspberrypi.org>
Date: Wed, 23 Sep 2026 09:57:49 -0700
Subject: [PATCH 1/5] chore: move tsc command off gulp

---
 packages/blockly/gulpfile.mjs                 |  2 --
 packages/blockly/package.json                 |  6 ++--
 packages/blockly/scripts/build_constants.mjs  | 30 +++++++++++++++++++
 .../blockly/scripts/gulpfiles/build_tasks.mjs | 15 ----------
 packages/blockly/scripts/tsc.mjs              | 17 +++++++++++
 5 files changed, 50 insertions(+), 20 deletions(-)
 create mode 100644 packages/blockly/scripts/build_constants.mjs
 create mode 100644 packages/blockly/scripts/tsc.mjs

diff --git a/packages/blockly/gulpfile.mjs b/packages/blockly/gulpfile.mjs
index f3e893444cc..bb5ab244b5c 100644
--- a/packages/blockly/gulpfile.mjs
+++ b/packages/blockly/gulpfile.mjs
@@ -28,7 +28,6 @@ import {
   langfiles,
   messages,
   minify,
-  tsc,
 } from './scripts/gulpfiles/build_tasks.mjs';
 import {cleanBuildDir, cleanReleaseDir} from './scripts/lib/fs_utils.mjs';
 
@@ -44,7 +43,6 @@ export default build;
 // prettier-ignore
 export {
   langfiles,
-  tsc,
   minify,
   build,
   prepareDemos,
diff --git a/packages/blockly/package.json b/packages/blockly/package.json
index f655fb024c7..af5266f12d2 100644
--- a/packages/blockly/package.json
+++ b/packages/blockly/package.json
@@ -94,7 +94,7 @@
     }
   },
   "scripts": {
-    "build": "gulp build",
+    "build": "npm run tsc && gulp build",
     "build-debug": "gulp build --verbose --debug",
     "build-debug-log": "npm run build:debug > build-debug.log 2>&1 && tail -3 build-debug.log",
     "build-strict": "gulp build --verbose --strict",
@@ -112,14 +112,14 @@
     "start": "npm run package && nx run @blockly/dev-tools:build && node \"scripts/prepare_advanced_playground.mjs\" && concurrently -n devtools-watch,blockly-watch,server \"nx watch --projects=@blockly/dev-tools --includeDependencies -- nx run rebuildAdvancedPlayground\" \"nx watch --projects=blockly -- nx run rebuildBlockly\" \"http-server ./ -s -o /tests/playground.html -c-1\"",
     "rebuildAdvancedPlayground": "npm run build --workspace=@blockly/dev-tools && node \"scripts/prepare_advanced_playground.mjs\"",
     "rebuildBlockly": "npm run build && node \"scripts/prepare_advanced_playground.mjs\"",
-    "tsc": "gulp tsc",
+    "tsc": "node \"scripts/tsc.mjs\"",
     "test": "nx run-many -p blockly --targets=lint,test-renamings,test-mocha-node,test-generators,test-type-definitions,test-compile-advanced,test-compile-advanced-browser",
     "test-browser": "npx nx run @blockly/block-test:build && npx mocha --config tests/browser/.mocharc.js",
     "test-mocha-node": "npm run test-mocha-typecheck && npx mocha --config tests/mocha/.mocharc.node.cjs \"tests/mocha/**/*_test.{js,ts}\"",
     "test-mocha-typecheck": "tsc -p tests/mocha/tsconfig.json",
     "test-generators": "node \"tests/generators/test_generators.mjs\"",
     "test-mocha-interactive": "npm run build && node scripts/prepare_mocha_bundle.mjs && concurrently -n tsc,tsc:tests,esbuild,python3 \"tsc --watch --preserveWatchOutput --outDir \"build/src\" --declarationDir \"build/declarations\"\" \"npm run test-mocha-typecheck -- --watch --preserveWatchOutput\" \"esbuild build/tests/bundle-entry.js --bundle --sourcemap --alias:blockly/core=./build/src/core/blockly.js --alias:blockly/blocks=./build/src/blocks/blocks.js --alias:blockly=./build/src/core/blockly.js --outfile=build/tests/mocha-bundle.js --servedir=. --serve=127.0.0.1:8080 --watch=forever --log-level=warning\" \"python3 -m webbrowser 'http://localhost:8080/tests/mocha/index.html'\"",
-    "test-compile-advanced": "gulp buildAdvancedCompilationTest --debug",
+    "test-compile-advanced": "npm run tsc && gulp buildAdvancedCompilationTest --debug",
     "test-compile-advanced-browser": "node \"tests/compile/webdriver.js\"",
     "test-renamings": "node \"tests/migration/validate-renamings.mjs\"",
     "test-type-definitions": "tsc -p ./tests/typescript/tsconfig.json -outDir \"build/src\"",
diff --git a/packages/blockly/scripts/build_constants.mjs b/packages/blockly/scripts/build_constants.mjs
new file mode 100644
index 00000000000..43a5def353f
--- /dev/null
+++ b/packages/blockly/scripts/build_constants.mjs
@@ -0,0 +1,30 @@
+import * as path from 'path';
+
+// Paths are all relative to the repository root.  Do not include
+// trailing slash.
+//
+// TODO(#5007): If you modify these values, you must also modify the
+// corresponding values in the following files:
+//
+// - tests/scripts/check_metadata.sh
+// - tests/scripts/update_metadata.sh
+
+// Directory to write compiled output to.
+export const BUILD_DIR = 'build';
+
+// Directory to write typings output to.
+export const TYPINGS_BUILD_DIR = path.join(BUILD_DIR, 'declarations');
+
+// Directory to write langfile output to.
+export const LANG_BUILD_DIR = path.join(BUILD_DIR, 'msg');
+
+// Directory where typescript compiler output can be found.
+// Matches the value in tsconfig.json: outDir
+export const TSC_OUTPUT_DIR = path.join(BUILD_DIR, 'src');
+
+// Directory for files generated by compiling test code.
+export const TEST_TSC_OUTPUT_DIR = path.join(BUILD_DIR, 'tests');
+
+// Directory in which to assemble (and from which to publish) the
+// blockly npm package.
+export const RELEASE_DIR = 'dist';
\ No newline at end of file
diff --git a/packages/blockly/scripts/gulpfiles/build_tasks.mjs b/packages/blockly/scripts/gulpfiles/build_tasks.mjs
index f8b6aabec11..ad3c798aa0b 100644
--- a/packages/blockly/scripts/gulpfiles/build_tasks.mjs
+++ b/packages/blockly/scripts/gulpfiles/build_tasks.mjs
@@ -331,19 +331,6 @@ const JSCOMP_OFF = [
   'visibility',
 ];
 
-/**
- * Builds Blockly as a JS program, by running tsc on all the files in
- * the core directory.
- */
-export function tsc(done) {
-  execSync(
-    `tsc -outDir "${TSC_OUTPUT_DIR}" -declarationDir "${TYPINGS_BUILD_DIR}"`,
-    {stdio: 'inherit'},
-  );
-  execSync(`node scripts/tsick.js "${TSC_OUTPUT_DIR}"`, {stdio: 'inherit'});
-  done();
-}
-
 /**
  * This task regenerates msg/json/en.js and msg/json/qqq.js from
  * msg/messages.js.
@@ -880,7 +867,6 @@ function compileAdvancedCompilationTest() {
 export const langfiles = gulp.parallel(buildLangfiles, buildLangfileShims);
 // function tsc, above
 export const minify = gulp.series(
-  tsc,
   buildChunkExporters,
   buildCompiled,
   buildShims,
@@ -890,6 +876,5 @@ export const build = gulp.parallel(minify, langfiles);
 // Manually-invokable targets, with prerequisites where required.
 // function messages, above
 export const buildAdvancedCompilationTest = gulp.series(
-  tsc,
   compileAdvancedCompilationTest,
 );
diff --git a/packages/blockly/scripts/tsc.mjs b/packages/blockly/scripts/tsc.mjs
new file mode 100644
index 00000000000..e6731c88135
--- /dev/null
+++ b/packages/blockly/scripts/tsc.mjs
@@ -0,0 +1,17 @@
+import {execSync} from 'child_process';
+
+import {TSC_OUTPUT_DIR, TYPINGS_BUILD_DIR} from './build_constants.mjs';
+
+/**
+ * Builds Blockly as a JS program, by running tsc on all the files in
+ * the core directory.
+ */
+function tsc() {
+  execSync(
+    `npx tsc -outDir "${TSC_OUTPUT_DIR}" -declarationDir "${TYPINGS_BUILD_DIR}"`,
+    {stdio: 'inherit'},
+  );
+  execSync(`node scripts/tsick.js "${TSC_OUTPUT_DIR}"`, {stdio: 'inherit'});
+}
+
+tsc();

From 4c697227be2cc7ceda4b465bacc8c2e1af7c672a Mon Sep 17 00:00:00 2001
From: lizschwab <liz.schwab@raspberrypi.org>
Date: Wed, 23 Sep 2026 10:25:12 -0700
Subject: [PATCH 2/5] chore: formatting

---
 packages/blockly/scripts/build_constants.mjs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/blockly/scripts/build_constants.mjs b/packages/blockly/scripts/build_constants.mjs
index 43a5def353f..f54900626fa 100644
--- a/packages/blockly/scripts/build_constants.mjs
+++ b/packages/blockly/scripts/build_constants.mjs
@@ -27,4 +27,4 @@ export const TEST_TSC_OUTPUT_DIR = path.join(BUILD_DIR, 'tests');
 
 // Directory in which to assemble (and from which to publish) the
 // blockly npm package.
-export const RELEASE_DIR = 'dist';
\ No newline at end of file
+export const RELEASE_DIR = 'dist';

From 5c6dfe69a67b1598019e12f4876fb3b62c12d6ec Mon Sep 17 00:00:00 2001
From: lizschwab <liz.schwab@raspberrypi.org>
Date: Wed, 23 Sep 2026 11:19:43 -0700
Subject: [PATCH 3/5] chore: remove unused reference

---
 packages/blockly/scripts/gulpfiles/build_tasks.mjs | 1 -
 1 file changed, 1 deletion(-)

diff --git a/packages/blockly/scripts/gulpfiles/build_tasks.mjs b/packages/blockly/scripts/gulpfiles/build_tasks.mjs
index ad3c798aa0b..33e3c1eadc4 100644
--- a/packages/blockly/scripts/gulpfiles/build_tasks.mjs
+++ b/packages/blockly/scripts/gulpfiles/build_tasks.mjs
@@ -28,7 +28,6 @@ import {
   LANG_BUILD_DIR,
   RELEASE_DIR,
   TSC_OUTPUT_DIR,
-  TYPINGS_BUILD_DIR,
 } from './config.mjs';
 
 import {posixPath, quote} from '../helpers.js';

From e5751baa45842d558722c39641aa74cbfbd9c890 Mon Sep 17 00:00:00 2001
From: lizschwab <liz.schwab@raspberrypi.org>
Date: Wed, 23 Sep 2026 15:22:47 -0700
Subject: [PATCH 4/5] chore: move langfiles and messages off gulp

---
 packages/blockly/gulpfile.mjs                 |   4 -
 packages/blockly/package.json                 |   6 +-
 packages/blockly/scripts/build_constants.mjs  |   7 +
 .../blockly/scripts/gulpfiles/build_tasks.mjs | 124 +-----------------
 packages/blockly/scripts/langfiles.mjs        | 104 +++++++++++++++
 packages/blockly/scripts/messages.mjs         |  44 +++++++
 6 files changed, 159 insertions(+), 130 deletions(-)
 create mode 100644 packages/blockly/scripts/langfiles.mjs
 create mode 100644 packages/blockly/scripts/messages.mjs

diff --git a/packages/blockly/gulpfile.mjs b/packages/blockly/gulpfile.mjs
index bb5ab244b5c..586e73be89e 100644
--- a/packages/blockly/gulpfile.mjs
+++ b/packages/blockly/gulpfile.mjs
@@ -25,8 +25,6 @@ import {
 import {
   build,
   buildAdvancedCompilationTest,
-  langfiles,
-  messages,
   minify,
 } from './scripts/gulpfiles/build_tasks.mjs';
 import {cleanBuildDir, cleanReleaseDir} from './scripts/lib/fs_utils.mjs';
@@ -42,7 +40,6 @@ export default build;
 //
 // prettier-ignore
 export {
-  langfiles,
   minify,
   build,
   prepareDemos,
@@ -55,7 +52,6 @@ export {
 //
 // prettier-ignore
 export {
-  messages, // Generate msg/json/en.json et al.
   clean,
   buildAdvancedCompilationTest,
 }
diff --git a/packages/blockly/package.json b/packages/blockly/package.json
index 2c849a97432..861eaecf5e7 100644
--- a/packages/blockly/package.json
+++ b/packages/blockly/package.json
@@ -94,7 +94,7 @@
     }
   },
   "scripts": {
-    "build": "npm run tsc && gulp build",
+    "build": "npm run tsc && gulp build && npm run langfiles",
     "build-debug": "gulp build --verbose --debug",
     "build-debug-log": "npm run build:debug > build-debug.log 2>&1 && tail -3 build-debug.log",
     "build-strict": "gulp build --verbose --strict",
@@ -102,10 +102,10 @@
     "clean": "gulp clean",
     "deployDemos": "npm ci && gulp deployDemos",
     "deployDemos:beta": "npm ci && gulp deployDemosBeta",
-    "messages": "gulp messages",
+    "messages": "node \"scripts/messages.mjs\"",
     "lint": "eslint .",
     "lint-fix": "eslint . --fix",
-    "langfiles": "gulp langfiles",
+    "langfiles": "node \"scripts/langfiles.mjs\"",
     "minify": "gulp minify",
     "package": "node scripts/package.mjs",
     "prepareDemos": "gulp prepareDemos",
diff --git a/packages/blockly/scripts/build_constants.mjs b/packages/blockly/scripts/build_constants.mjs
index f54900626fa..1b2ae1339f0 100644
--- a/packages/blockly/scripts/build_constants.mjs
+++ b/packages/blockly/scripts/build_constants.mjs
@@ -28,3 +28,10 @@ export const TEST_TSC_OUTPUT_DIR = path.join(BUILD_DIR, 'tests');
 // Directory in which to assemble (and from which to publish) the
 // blockly npm package.
 export const RELEASE_DIR = 'dist';
+
+/**
+ * Path to the python runtime.
+ * This will normalize the command across platforms (e.g. python3 on Linux and
+ * Mac, python on Windows).
+ */
+export const PYTHON = process.platform === 'win32' ? 'python' : 'python3';
diff --git a/packages/blockly/scripts/gulpfiles/build_tasks.mjs b/packages/blockly/scripts/gulpfiles/build_tasks.mjs
index 33e3c1eadc4..1f35db6e387 100644
--- a/packages/blockly/scripts/gulpfiles/build_tasks.mjs
+++ b/packages/blockly/scripts/gulpfiles/build_tasks.mjs
@@ -13,7 +13,6 @@ import rename from 'gulp-rename';
 import replace from 'gulp-replace';
 import sourcemaps from 'gulp-sourcemaps';
 
-import {execSync} from 'child_process';
 import * as fs from 'fs';
 import * as fsPromises from 'fs/promises';
 import * as path from 'path';
@@ -25,7 +24,6 @@ import {hideBin} from 'yargs/helpers';
 
 import {
   BUILD_DIR,
-  LANG_BUILD_DIR,
   RELEASE_DIR,
   TSC_OUTPUT_DIR,
 } from './config.mjs';
@@ -39,13 +37,6 @@ const argv = yargs(hideBin(process.argv)).parse();
 //                        Build                           //
 ////////////////////////////////////////////////////////////
 
-/**
- * Path to the python runtime.
- * This will normalize the command across platforms (e.g. python3 on Linux and
- * Mac, python on Windows).
- */
-const PYTHON = process.platform === 'win32' ? 'python' : 'python3';
-
 /**
  * Posix version of TSC_OUTPUT_DIR
  */
@@ -330,80 +321,6 @@ const JSCOMP_OFF = [
   'visibility',
 ];
 
-/**
- * This task regenerates msg/json/en.js and msg/json/qqq.js from
- * msg/messages.js.
- */
-export function messages(done) {
-  // Run js_to_json.py
-  const jsToJsonCmd = `${PYTHON} scripts/i18n/js_to_json.py \
-      --input_file ${path.join('msg', 'messages.js')} \
-      --output_dir ${path.join('msg', 'json')} \
-      --quiet`;
-  execSync(jsToJsonCmd, {stdio: 'inherit'});
-
-  console.log(`
-Regenerated several flies in msg/json/.  Now run
-
-    git diff msg/json/*.json
-
-and check that operation has not overwritten any modifications made to
-hints, etc. by the TranslateWiki volunteers.  If it has, backport
-their changes to msg/messages.js and re-run 'npm run messages'.
-
-Once you are satisfied that any new hints have been backported you may
-go ahead and commit the changes, but note that the messages script
-will have removed the translator credits - be careful not to commit
-this removal!
-`);
-
-  done();
-}
-
-var languages = null;
-
-/**
- * Get list of languages to build langfiles and/or shims for, based on .json
- * files in msg/json/, skipping certain entries that do not correspond to an
- * actual language).  Results are cached as this is called from both
- * buildLangfiles and buildLangfileShims.
- */
-function getLanguages() {
-  if (!languages) {
-    const skip = /^(keys|synonyms|qqq|constants)\.json$/;
-    languages = fs
-      .readdirSync(path.join('msg', 'json'))
-      .filter((file) => file.endsWith('json') && !skip.test(file))
-      .map((file) => file.replace(/\.json$/, ''));
-  }
-  return languages;
-}
-
-/**
- * This task builds Blockly's lang files.
- *     msg/*.js
- */
-function buildLangfiles(done) {
-  // Create output directory.
-  fs.mkdirSync(LANG_BUILD_DIR, {recursive: true});
-
-  // Run create_messages.py.
-  const inputFiles = getLanguages().map((lang) =>
-    path.join('msg', 'json', `${lang}.json`),
-  );
-
-  const createMessagesCmd = `${PYTHON} ./scripts/i18n/create_messages.py \
-  --source_lang_file ${path.join('msg', 'json', 'en.json')} \
-  --source_synonym_file ${path.join('msg', 'json', 'synonyms.json')} \
-  --source_constants_file ${path.join('msg', 'json', 'constants.json')} \
-  --key_file ${path.join('msg', 'json', 'keys.json')} \
-  --output_dir ${LANG_BUILD_DIR} \
-  --quiet ${inputFiles.join(' ')}`;
-  execSync(createMessagesCmd, {stdio: 'inherit'});
-
-  done();
-}
-
 /**
  * Return the path to the generated chunk exporter for the given
  * chunk, relative to TSC_OUTPUT_DIR.
@@ -786,43 +703,6 @@ ${exportedNames.map((name) => `  ${name},`).join('\n')}
   await fsPromises.rm(TMP_PACKAGE_JSON);
 }
 
-/**
- * This task builds the ESM wrappers used by the langfiles "import"
- * entrypoints declared in package.json.
- */
-async function buildLangfileShims() {
-  // Create output directory.
-  fs.mkdirSync(path.join(RELEASE_DIR, 'msg'), {recursive: true});
-
-  // Get the names of the exports from the langfile by require()ing
-  // msg/messages.js and letting it mutate the (global) Blockly.Msg.
-  // (We have to do it this way because messages.js is a script and
-  // not a CJS module with exports.)
-  globalThis.Blockly = {Msg: {}};
-  await import('../../msg/messages.js');
-  const exportedNames = Object.keys(globalThis.Blockly.Msg);
-  delete globalThis.Blockly;
-
-  await Promise.all(
-    getLanguages().map(async (lang) => {
-      // Write an ESM wrapper that imports the CJS module and re-exports
-      // its named exports.
-      const cjsPath = `./${lang}.js`;
-      const wrapperPath = path.join(RELEASE_DIR, 'msg', `${lang}.mjs`);
-      const safeLang = lang.replace(/-/g, '_');
-
-      await fsPromises.writeFile(
-        wrapperPath,
-        `import ${safeLang} from '${cjsPath}';
-export const {
-${exportedNames.map((name) => `  ${name},`).join('\n')}
-} = ${safeLang};
-`,
-      );
-    }),
-  );
-}
-
 /**
  * This task uses Closure Compiler's ADVANCED_OPTIMIZATIONS mode to
  * compile together Blockly core, blocks and generators with a simple
@@ -862,15 +742,13 @@ function compileAdvancedCompilationTest() {
     .pipe(gulp.dest('./tests/compile/'));
 }
 
-// Main sequence targets.  Each should invoke any immediate prerequisite(s).
-export const langfiles = gulp.parallel(buildLangfiles, buildLangfileShims);
 // function tsc, above
 export const minify = gulp.series(
   buildChunkExporters,
   buildCompiled,
   buildShims,
 );
-export const build = gulp.parallel(minify, langfiles);
+export const build = gulp.parallel(minify);
 
 // Manually-invokable targets, with prerequisites where required.
 // function messages, above
diff --git a/packages/blockly/scripts/langfiles.mjs b/packages/blockly/scripts/langfiles.mjs
new file mode 100644
index 00000000000..b2cc495eba2
--- /dev/null
+++ b/packages/blockly/scripts/langfiles.mjs
@@ -0,0 +1,104 @@
+/**
+ * @license
+ * Copyright 2026 Raspberry Pi Foundation
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/**
+ * @fileoverview Functions for building language files.
+ */
+
+import {execSync} from 'child_process';
+import {mkdirSync, readdirSync} from 'fs';
+import {writeFile} from 'fs/promises';
+import * as path from 'path';
+
+import {LANG_BUILD_DIR, PYTHON, RELEASE_DIR} from './build_constants.mjs';
+
+let languages = null;
+
+/**
+ * Get list of languages to build langfiles and/or shims for, based on .json
+ * files in msg/json/, skipping certain entries that do not correspond to an
+ * actual language).  Results are cached as this is called from both
+ * buildLangfiles and buildLangfileShims.
+ */
+function getLanguages() {
+  if (!languages) {
+    const skip = /^(keys|synonyms|qqq|constants)\.json$/;
+    languages = readdirSync(path.join('msg', 'json'))
+      .filter((file) => file.endsWith('json') && !skip.test(file))
+      .map((file) => file.replace(/\.json$/, ''));
+  }
+  return languages;
+}
+
+/**
+ * This task builds Blockly's lang files.
+ *     msg/*.js
+ */
+function buildLangfiles() {
+  // Create output directory.
+  mkdirSync(LANG_BUILD_DIR, {recursive: true});
+
+  // Run create_messages.py.
+  const inputFiles = getLanguages().map((lang) =>
+    path.join('msg', 'json', `${lang}.json`),
+  );
+
+  const createMessagesCmd = `${PYTHON} ./scripts/i18n/create_messages.py \
+  --source_lang_file ${path.join('msg', 'json', 'en.json')} \
+  --source_synonym_file ${path.join('msg', 'json', 'synonyms.json')} \
+  --source_constants_file ${path.join('msg', 'json', 'constants.json')} \
+  --key_file ${path.join('msg', 'json', 'keys.json')} \
+  --output_dir ${LANG_BUILD_DIR} \
+  --quiet ${inputFiles.join(' ')}`;
+  execSync(createMessagesCmd, {stdio: 'inherit'});
+}
+
+/**
+ * This task builds the ESM wrappers used by the langfiles "import"
+ * entrypoints declared in package.json.
+ */
+async function buildLangfileShims() {
+  // Create output directory.
+  mkdirSync(path.join(RELEASE_DIR, 'msg'), {recursive: true});
+
+  // Get the names of the exports from the langfile by require()ing
+  // msg/messages.js and letting it mutate the (global) Blockly.Msg.
+  // (We have to do it this way because messages.js is a script and
+  // not a CJS module with exports.)
+  globalThis.Blockly = {Msg: {}};
+  await import('../msg/messages.js');
+  const exportedNames = Object.keys(globalThis.Blockly.Msg);
+  delete globalThis.Blockly;
+
+  await Promise.all(
+    getLanguages().map(async (lang) => {
+      // Write an ESM wrapper that imports the CJS module and re-exports
+      // its named exports.
+      const cjsPath = `./${lang}.js`;
+      const wrapperPath = path.join(RELEASE_DIR, 'msg', `${lang}.mjs`);
+      const safeLang = lang.replace(/-/g, '_');
+
+      await writeFile(
+        wrapperPath,
+        `import ${safeLang} from '${cjsPath}';
+export const {
+${exportedNames.map((name) => `  ${name},`).join('\n')}
+} = ${safeLang};
+`,
+      );
+    }),
+  );
+}
+
+/**
+ * Run all of the functions needed to build langfiles.
+ */
+async function langfiles() {
+  await buildLangfiles();
+  await buildLangfileShims();
+}
+
+await langfiles();
diff --git a/packages/blockly/scripts/messages.mjs b/packages/blockly/scripts/messages.mjs
new file mode 100644
index 00000000000..66d333d8489
--- /dev/null
+++ b/packages/blockly/scripts/messages.mjs
@@ -0,0 +1,44 @@
+/**
+ * @license
+ * Copyright 2026 Raspberry Pi Foundation
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/**
+ * @fileoverview Functions for generating message files
+ */
+
+import {execSync} from 'child_process';
+import * as path from 'path';
+
+import {PYTHON} from './build_constants.mjs';
+
+/**
+ * This task regenerates msg/json/en.js and msg/json/qqq.js from
+ * msg/messages.js.
+ */
+export function messages() {
+  // Run js_to_json.py
+  const jsToJsonCmd = `${PYTHON} scripts/i18n/js_to_json.py \
+      --input_file ${path.join('msg', 'messages.js')} \
+      --output_dir ${path.join('msg', 'json')} \
+      --quiet`;
+  execSync(jsToJsonCmd, {stdio: 'inherit'});
+
+  console.log(`
+Regenerated several flies in msg/json/.  Now run
+
+    git diff msg/json/*.json
+
+and check that operation has not overwritten any modifications made to
+hints, etc. by the TranslateWiki volunteers.  If it has, backport
+their changes to msg/messages.js and re-run 'npm run messages'.
+
+Once you are satisfied that any new hints have been backported you may
+go ahead and commit the changes, but note that the messages script
+will have removed the translator credits - be careful not to commit
+this removal!
+`);
+}
+
+messages();

From 6cc47f63680c60ac687a6f85a192cc13494ee08a Mon Sep 17 00:00:00 2001
From: lizschwab <liz.schwab@raspberrypi.org>
Date: Thu, 24 Sep 2026 10:40:17 -0700
Subject: [PATCH 5/5] chore: move clean script off gulp

---
 packages/blockly/gulpfile.mjs      |  5 -----
 packages/blockly/package.json      |  2 +-
 packages/blockly/scripts/clean.mjs | 14 ++++++++++++++
 3 files changed, 15 insertions(+), 6 deletions(-)
 create mode 100644 packages/blockly/scripts/clean.mjs

diff --git a/packages/blockly/gulpfile.mjs b/packages/blockly/gulpfile.mjs
index 586e73be89e..d21e4874c82 100644
--- a/packages/blockly/gulpfile.mjs
+++ b/packages/blockly/gulpfile.mjs
@@ -16,7 +16,6 @@
 //
 // organize-imports-ignore
 
-import {parallel} from 'gulp';
 import {
   deployDemos,
   deployDemosBeta,
@@ -27,9 +26,6 @@ import {
   buildAdvancedCompilationTest,
   minify,
 } from './scripts/gulpfiles/build_tasks.mjs';
-import {cleanBuildDir, cleanReleaseDir} from './scripts/lib/fs_utils.mjs';
-
-const clean = parallel(cleanBuildDir, cleanReleaseDir);
 
 // Default target if gulp invoked without specifying.
 export default build;
@@ -52,6 +48,5 @@ export {
 //
 // prettier-ignore
 export {
-  clean,
   buildAdvancedCompilationTest,
 }
diff --git a/packages/blockly/package.json b/packages/blockly/package.json
index 861eaecf5e7..f3ccbf0dccc 100644
--- a/packages/blockly/package.json
+++ b/packages/blockly/package.json
@@ -99,7 +99,7 @@
     "build-debug-log": "npm run build:debug > build-debug.log 2>&1 && tail -3 build-debug.log",
     "build-strict": "gulp build --verbose --strict",
     "build-strict-log": "npm run build:strict > build-debug.log 2>&1 && tail -3 build-debug.log",
-    "clean": "gulp clean",
+    "clean": "node \"scripts/clean.mjs\"",
     "deployDemos": "npm ci && gulp deployDemos",
     "deployDemos:beta": "npm ci && gulp deployDemosBeta",
     "messages": "node \"scripts/messages.mjs\"",
diff --git a/packages/blockly/scripts/clean.mjs b/packages/blockly/scripts/clean.mjs
new file mode 100644
index 00000000000..26c133caf1a
--- /dev/null
+++ b/packages/blockly/scripts/clean.mjs
@@ -0,0 +1,14 @@
+/**
+ * @license
+ * Copyright 2026 Raspberry Pi Foundation
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/**
+ * @fileoverview Script to clean the workspace of old build/package/etc. files.
+ */
+
+import {cleanBuildDir, cleanReleaseDir} from './lib/fs_utils.mjs';
+
+await cleanBuildDir();
+await cleanReleaseDir();