diff --git a/test/nstore_test.cpp b/test/nstore_test.cpp
new file mode 100644
index 00000000..a3e40490
--- /dev/null
+++ b/test/nstore_test.cpp
@@ -0,0 +1,39 @@
+#include <boost/histogram/detail/nstore.hpp>
+#include <boost/histogram/detail/wtype.hpp>
+#define BOOST_TEST_MODULE nstore_test
+#include <boost/test/unit_test.hpp>
+#include <boost/test/test_tools.hpp>
+#include <boost/move/move.hpp>
+#include <sstream>
+#include <string>
+#include <limits>
+using namespace boost::histogram::detail;
+
+BOOST_AUTO_TEST_CASE(wtype_streamer)
+{
+    std::ostringstream os;
+    wtype w;
+    w.w = 1.2;
+    w.w2 = 2.3;
+    os << w;
+    BOOST_CHECK_EQUAL(os.str(), std::string("(1.2,2.3)"));
+}
+
+BOOST_AUTO_TEST_CASE(nstore_bad_alloc)
+{
+    BOOST_CHECK_THROW(nstore(nstore::size_type(-1)),
+                      std::bad_alloc);
+}
+
+BOOST_AUTO_TEST_CASE(nstore_grow)
+{
+    double x = 1.0;
+    nstore n(1);
+    n.increase(0);
+    for (unsigned i = 0; i < 64; ++i) {
+        n += n;
+        x += x;
+        BOOST_CHECK_EQUAL(n.value(0), x);
+    }
+    BOOST_CHECK_EQUAL(n.variance(0), x);
+}