diff --git a/.github/workflows/dev.yml b/.github/workflows/dev.yml
index f6a7d2f435..31c929ec28 100644
--- a/.github/workflows/dev.yml
+++ b/.github/workflows/dev.yml
@@ -452,7 +452,7 @@ jobs:
             --coverage.thresholds.lines=0 --coverage.thresholds.functions=0 \
             --coverage.thresholds.branches=0 --coverage.thresholds.statements=0
 
-      # Vitest names blobs `.vitest-reports/blob-<index>-<count>.json`, so the two
+      # Vitest names blobs `.vitest/blob/blob-<index>-<count>.json`, so the two
       # shards produce distinct filenames and merge-multiple cannot clobber them.
       # That directory is dot-prefixed, and upload-artifact skips hidden paths
       # unless told otherwise — without include-hidden-files it silently matches
@@ -462,7 +462,7 @@ jobs:
         if: ${{ !cancelled() && steps.test-ckeditor5.outcome == 'success' }}
         with:
           name: ckeditor5-blob-${{ matrix.shard }}
-          path: packages/ckeditor5/.vitest-reports/
+          path: packages/ckeditor5/.vitest/blob/
           include-hidden-files: true
           if-no-files-found: error
           retention-days: 1
@@ -500,7 +500,7 @@ jobs:
         with:
           pattern: ckeditor5-blob-*
           merge-multiple: true
-          path: packages/ckeditor5/.vitest-reports
+          path: packages/ckeditor5/.vitest/blob
 
       # Re-runs no tests; it replays the blobs to produce the junit and lcov
       # output and to evaluate the package's real coverage thresholds over the
diff --git a/vitest.config.ts b/vitest.config.ts
index b3917098d1..690ac2cb4c 100644
--- a/vitest.config.ts
+++ b/vitest.config.ts
@@ -5,6 +5,10 @@ export default defineConfig({
     projects: [
         "packages/*/vitest.config.ts",
         "packages/*/vite.config.ts",
+        // ckeditor5 is the one package with both, and its vite.config.ts only builds the library —
+        // the tests live in vitest.config.ts. Registering both gives two projects called
+        // "@triliumnext/ckeditor5", which vitest rejects.
+        "!packages/ckeditor5/vite.config.ts",
         "apps/*/vitest.config.ts",
         "apps/*/vite.config.ts",
         "apps/*/vite.config.mts",