diff --git a/.github/workflows/build-desktop-dev.yml b/.github/workflows/build-desktop-dev.yml
index 517bb161..e973700b 100644
--- a/.github/workflows/build-desktop-dev.yml
+++ b/.github/workflows/build-desktop-dev.yml
@@ -126,6 +126,7 @@ jobs:
       - name: Build sidecars
         working-directory: desktop
         env:
+          BUN_INSTALL_CACHE_DIR: ${{ runner.temp }}/bun-install-cache
           TAURI_ENV_TARGET_TRIPLE: ${{ matrix.rust_target }}
         run: bun run build:sidecars
 
diff --git a/.github/workflows/release-desktop.yml b/.github/workflows/release-desktop.yml
index 74952d01..e10b1ef2 100644
--- a/.github/workflows/release-desktop.yml
+++ b/.github/workflows/release-desktop.yml
@@ -158,6 +158,7 @@ jobs:
       - name: Build sidecars
         working-directory: desktop
         env:
+          BUN_INSTALL_CACHE_DIR: ${{ runner.temp }}/bun-install-cache
           TAURI_ENV_TARGET_TRIPLE: ${{ matrix.rust_target }}
         run: bun run build:sidecars
 
diff --git a/scripts/pr/release-workflow.test.ts b/scripts/pr/release-workflow.test.ts
index 13d848aa..b1a0c0d6 100644
--- a/scripts/pr/release-workflow.test.ts
+++ b/scripts/pr/release-workflow.test.ts
@@ -10,4 +10,23 @@ describe('release desktop workflow', () => {
     expect(workflow).not.toContain('needs: quality-preflight')
     expect(workflow).toContain('name: Build (${{ matrix.label }})')
   })
+
+  test('desktop build workflows keep Bun compile cache on the runner work drive', () => {
+    for (const workflowPath of [
+      '.github/workflows/build-desktop-dev.yml',
+      '.github/workflows/release-desktop.yml',
+    ]) {
+      const workflow = readFileSync(workflowPath, 'utf8')
+      const buildSidecarsStep = workflow.match(
+        /- name: Build sidecars[\s\S]*?run: bun run build:sidecars/,
+      )?.[0]
+
+      expect(buildSidecarsStep, workflowPath).toContain(
+        'BUN_INSTALL_CACHE_DIR: ${{ runner.temp }}/bun-install-cache',
+      )
+      expect(buildSidecarsStep, workflowPath).toContain(
+        'TAURI_ENV_TARGET_TRIPLE: ${{ matrix.rust_target }}',
+      )
+    }
+  })
 })