diff --git a/metropolis/pkg/logtree/zap_test.go b/metropolis/pkg/logtree/zap_test.go
new file mode 100644
index 0000000..3917cd8
--- /dev/null
+++ b/metropolis/pkg/logtree/zap_test.go
@@ -0,0 +1,42 @@
+package logtree
+
+import (
+	"testing"
+
+	"go.uber.org/zap"
+)
+
+func TestZapify(t *testing.T) {
+	lt := New()
+
+	z := Zapify(lt.MustLeveledFor("zap"), zap.InfoLevel)
+	z.Info("foo", zap.String("strp", "strv"), zap.Int("intp", 42))
+	z.Warn("foo!", zap.String("strp", "strv"), zap.Int("intp", 1337))
+	z.Error("foo!!")
+
+	res, err := lt.Read("zap", WithBacklog(BacklogAllAvailable))
+	if err != nil {
+		t.Fatalf("Read: %v", err)
+	}
+	defer res.Close()
+
+	if want, got := 3, len(res.Backlog); want != got {
+		t.Errorf("Wanted %d entries, got %d", want, got)
+	} else {
+		for i, te := range []struct {
+			msg string
+			sev Severity
+		}{
+			{`foo {"intp":42,"strp":"strv"}`, INFO},
+			{`foo! {"intp":1337,"strp":"strv"}`, WARNING},
+			{`foo!!`, ERROR},
+		} {
+			if want, got := te.msg, res.Backlog[i].Leveled.messages[0]; want != got {
+				t.Errorf("Line %d: wanted message %q, got %q", i, want, got)
+			}
+			if want, got := te.sev, res.Backlog[i].Leveled.severity; want != got {
+				t.Errorf("Line %d: wanted level %s, got %s", i, want, got)
+			}
+		}
+	}
+}