diff --git a/pyproject.toml b/pyproject.toml
index 2297683..2060871 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -4,7 +4,7 @@ build-backend = "scikit_build_core.build"
 
 [project]
 name = "openscad_cpp_evaluator"
-version = "0.32.1"
+version = "0.32.2"
 description = "C++ OpenSCAD evaluator with Python bindings"
 readme = "README.md"
 requires-python = ">=3.12"
diff --git a/src/builtins/function_builtins.cpp b/src/builtins/function_builtins.cpp
index 67825df..4c36351 100644
--- a/src/builtins/function_builtins.cpp
+++ b/src/builtins/function_builtins.cpp
@@ -691,8 +691,29 @@ Value evalBuiltinFunction(Evaluator& ev, const std::string& name, const CallArgs
             }
             return Value{false};
         }
-        case BuiltinFnId::Version: return numList({2025.0, 1.0, 1.0});
-        case BuiltinFnId::VersionNum: return Value{20250101.0};
+        // The OpenSCAD release we track. version_num() is that same
+        // year/month/day folded as y * 10000 + m * 100 + d, exactly like the
+        // reference's own builtin_version_num (builtin_functions.cc).
+        case BuiltinFnId::Version: return numList({2026.0, 1.0, 1.0});
+        case BuiltinFnId::VersionNum: {
+            // The optional vector argument the reference also accepts: with
+            // no argument this is our own version() folded; with one, it is
+            // whatever [y, m] / [y, m, d] the caller passed, so
+            // version_num([2019, 5, 0]) == 20190500 regardless of what
+            // release we report. A 2-element vector defaults the day to 0
+            // (getVec3's own defaultval), and anything else -- a non-list, a
+            // wrong length, a non-numeric element -- is undef.
+            //
+            // One deliberate divergence: the reference's size-2 path ignores
+            // getVec2's own failure and folds uninitialized doubles for e.g.
+            // version_num(["a", "b"]). That is undef here rather than
+            // whatever happened to be on the stack.
+            const Value* arg = args.findPositional(0);
+            if (!arg) return Value{20260101.0};
+            const auto v = allNumericList(*arg);
+            if (!v || (v->size() != 2 && v->size() != 3)) return Value{};
+            return Value{(*v)[0] * 10000.0 + (*v)[1] * 100.0 + (v->size() == 3 ? (*v)[2] : 0.0)};
+        }
         case BuiltinFnId::ParentModule:
             return ev.parentModuleName(static_cast<int>(toDoubleLenient(getArg(args, 0, "index", Value{0.0}))));
     }
diff --git a/tests/test_function_builtins.cpp b/tests/test_function_builtins.cpp
index d6d647d..b77efac 100644
--- a/tests/test_function_builtins.cpp
+++ b/tests/test_function_builtins.cpp
@@ -369,7 +369,28 @@ TEST(StringListBuiltins, FunctionValuedObjectMemberIsCallable) {
 
 TEST(StringListBuiltins, VersionBuiltins) {
     Evaluator ev;
-    EXPECT_DOUBLE_EQ(asNum(evalSrc("version_num()", ev)), 20250101.0);
+    EXPECT_DOUBLE_EQ(asNum(evalSrc("version_num()", ev)), 20260101.0);
+}
+
+// version_num() also takes the optional vector the reference's own
+// builtin_version_num does -- it folds whatever y/m/d it is handed, not just
+// this build's release.
+TEST(StringListBuiltins, VersionNumFoldsAGivenVersionVector) {
+    Evaluator ev;
+    EXPECT_DOUBLE_EQ(asNum(evalSrc("version_num([2019, 5, 0])", ev)), 20190500.0);
+    EXPECT_DOUBLE_EQ(asNum(evalSrc("version_num([2021, 1, 0])", ev)), 20210100.0);
+    // A 2-element vector defaults the day to 0 (getVec3's own defaultval).
+    EXPECT_DOUBLE_EQ(asNum(evalSrc("version_num([2019, 5])", ev)), 20190500.0);
+}
+
+TEST(StringListBuiltins, VersionNumRejectsAnythingButA2Or3NumberVector) {
+    Evaluator ev;
+    EXPECT_TRUE(isUndef(evalSrc("version_num(5)", ev)));
+    EXPECT_TRUE(isUndef(evalSrc("version_num(undef)", ev)));
+    EXPECT_TRUE(isUndef(evalSrc("version_num([2019])", ev)));
+    EXPECT_TRUE(isUndef(evalSrc("version_num([2019, 5, 0, 7])", ev)));
+    EXPECT_TRUE(isUndef(evalSrc("version_num([\"a\", \"b\"])", ev)));
+    EXPECT_TRUE(isUndef(evalSrc("version_num([\"a\", \"b\", \"c\"])", ev)));
 }
 
 TEST(StringListBuiltins, VersionReturnsThreeElementList) {
@@ -377,6 +398,12 @@ TEST(StringListBuiltins, VersionReturnsThreeElementList) {
     Value v = evalSrc("version()", ev);
     const auto& items = asList(v);
     ASSERT_EQ(items.size(), 3u);
+    // Pinned to the same release version_num() reports above -- the reference
+    // derives one from the other (y * 10000 + m * 100 + d, see
+    // builtin_version_num), so the two must not drift apart here either.
+    EXPECT_DOUBLE_EQ(asNum(items[0]), 2026.0);
+    EXPECT_DOUBLE_EQ(asNum(items[1]), 1.0);
+    EXPECT_DOUBLE_EQ(asNum(items[2]), 1.0);
 }
 
 TEST(StringListBuiltins, IsFunctionAndIsObject) {
diff --git a/uv.lock b/uv.lock
index 2a610b7..baf59b7 100644
--- a/uv.lock
+++ b/uv.lock
@@ -55,7 +55,7 @@ wheels = [
 
 [[package]]
 name = "openscad-cpp-evaluator"
-version = "0.32.1"
+version = "0.32.2"
 source = { editable = "." }
 dependencies = [
     { name = "numpy" },