From 5dd74f8523842740bd081e55a39d6b1652b4171b Mon Sep 17 00:00:00 2001
From: Aidan Timson <aidan@timmo.dev>
Date: Mon, 15 Dec 2025 09:56:02 +0000
Subject: [PATCH] Split modern and legacy builds

---
 .github/workflows/ci.yaml    |  8 ++++++--
 build-scripts/gulp/rspack.js | 25 ++++++++++++++++++++-----
 2 files changed, 26 insertions(+), 7 deletions(-)

diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index e4afbaef97..02021293a6 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -71,9 +71,12 @@ jobs:
       - name: Run Tests
         run: yarn run test
   build:
-    name: Build frontend
+    name: Build frontend (${{ matrix.target }})
     needs: [lint, test]
     runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        target: [modern, legacy]
     steps:
       - name: Check out files from GitHub
         uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6.0.1
@@ -88,10 +91,11 @@ jobs:
         run: ./node_modules/.bin/gulp build-app
         env:
           IS_TEST: "true"
+          BUILD_TARGET: ${{ matrix.target }}
       - name: Upload bundle stats
         uses: actions/upload-artifact@330a01c490aca151604b8cf639adc76d48f6c5d4 # v5.0.0
         with:
-          name: frontend-bundle-stats
+          name: frontend-bundle-stats-${{ matrix.target }}
           path: build/stats/*.json
           if-no-files-found: error
   supervisor:
diff --git a/build-scripts/gulp/rspack.js b/build-scripts/gulp/rspack.js
index 84f9d71079..c0caee5025 100644
--- a/build-scripts/gulp/rspack.js
+++ b/build-scripts/gulp/rspack.js
@@ -17,6 +17,18 @@ import {
   createLandingPageConfig,
 } from "../rspack.cjs";
 
+const selectBuildTargets = () => {
+  const target = process.env.BUILD_TARGET?.toLowerCase();
+  switch (target) {
+    case "modern":
+      return [true];
+    case "legacy":
+      return [false];
+    default:
+      return [true, false];
+  }
+};
+
 const bothBuilds = (createConfigFunc, params) => [
   createConfigFunc({ ...params, latestBuild: true }),
   createConfigFunc({ ...params, latestBuild: false }),
@@ -112,11 +124,14 @@ gulp.task("rspack-watch-app", () => {
 
 gulp.task("rspack-prod-app", () =>
   prodBuild(
-    bothBuilds(createAppConfig, {
-      isProdBuild: true,
-      isStatsBuild: env.isStatsBuild(),
-      isTestBuild: env.isTestBuild(),
-    })
+    selectBuildTargets().map((latestBuild) =>
+      createAppConfig({
+        isProdBuild: true,
+        isStatsBuild: env.isStatsBuild(),
+        isTestBuild: env.isTestBuild(),
+        latestBuild,
+      })
+    )
   )
 );