diff --git a/nbdev/test.py b/nbdev/test.py
index 8ba0ec06d..2cdbe9b30 100644
--- a/nbdev/test.py
+++ b/nbdev/test.py
@@ -48,12 +48,11 @@ async def test_nb(
         fm = nb_frontmatter(nb)
         if str2bool(fm.get('skip_exec', False)) or nb_lang(nb) != 'python': return True, 0
 
+        dflt = fm_default_eval(fm)
         def _no_eval(cell):
             if cell.cell_type != 'code': return True
-            if 'nbdev_export'+'(' in cell.source: return True
-            direc = getattr(cell, 'directives_', {}) or {}
-            if direc.get('eval', '').lower() == 'false': return True
-            return flags & direc.keys()
+            if not does_cell_eval(cell, dflt): return True
+            return flags & (getattr(cell, 'directives_', {}) or {}).keys()
 
         start = time.time()
         if profile is None: profile = bool(get_config(fn.parent).exec_profile)
diff --git a/nbs/api/12_test.ipynb b/nbs/api/12_test.ipynb
index e0c5cfe35..357d3b9b1 100644
--- a/nbs/api/12_test.ipynb
+++ b/nbs/api/12_test.ipynb
@@ -76,12 +76,11 @@
     "        fm = nb_frontmatter(nb)\n",
     "        if str2bool(fm.get('skip_exec', False)) or nb_lang(nb) != 'python': return True, 0\n",
     "\n",
+    "        dflt = fm_default_eval(fm)\n",
     "        def _no_eval(cell):\n",
     "            if cell.cell_type != 'code': return True\n",
-    "            if 'nbdev_export'+'(' in cell.source: return True\n",
-    "            direc = getattr(cell, 'directives_', {}) or {}\n",
-    "            if direc.get('eval', '').lower() == 'false': return True\n",
-    "            return flags & direc.keys()\n",
+    "            if not does_cell_eval(cell, dflt): return True\n",
+    "            return flags & (getattr(cell, 'directives_', {}) or {}).keys()\n",
     "\n",
     "        start = time.time()\n",
     "        if profile is None: profile = bool(get_config(fn.parent).exec_profile)\n",
@@ -314,7 +313,31 @@
    "id": "8ee3f4db",
    "metadata": {},
    "source": [
-    "## Eval -"
+    "## Eval"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "0317b83e",
+   "metadata": {},
+   "source": [
+    "`test_nb` decides which cells run through the `eval` cascade (`fastcore.nbio.does_cell_eval`): a cell's own `#| eval:` directive wins; otherwise the notebook-level `eval` directive — in frontmatter, or the notebook's `metadata.nbdev` mapping — sets the default; with neither, cells run. `#| eval: false` therefore skips one cell, as it always has, while a notebook-level `eval: false` flips the whole notebook to opt-in: only cells marked `#| eval: true` run, which suits a slow or service-dependent notebook where just a few cells are worth testing. Unlike `skip_exec: true`, which skips a notebook unconditionally, marked cells still run — here the unmarked cell would raise if executed, so the passing test is the proof it was skipped:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "2c358146",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "with tempfile.TemporaryDirectory() as td:\n",
+    "    cells = [mk_cell('---\\neval: false\\n---', 'raw'), mk_cell('raise Exception(\"unmarked: must not run\")'),\n",
+    "        mk_cell('#| eval: true\\nx = 1')]\n",
+    "    fn = Path(td)/'optin.ipynb'\n",
+    "    write_nb(new_nb(cells), fn)\n",
+    "    success,_ = await test_nb(fn)\n",
+    "assert success"
    ]
   },
   {
diff --git a/pyproject.toml b/pyproject.toml
index 331ef3ecd..730df1c54 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -19,7 +19,7 @@ classifiers = [
     "License :: OSI Approved :: Apache Software License",
 ]
 dynamic = ["version"]
-dependencies = [ "fastcore>=2.2.3", "execnb>=0.2.11", "astunparse", "ghapi>=2.0.2", "watchdog", "asttokens",
+dependencies = [ "fastcore>=2.2.7", "execnb>=0.2.11", "astunparse", "ghapi>=2.0.2", "watchdog", "asttokens",
     "setuptools", "build", "fastgit>=0.0.7", "pyyaml", "tomli; python_version < '3.11'", ]
 
 [project.optional-dependencies]