diff --git a/cmd/transpile/main_test.go b/cmd/transpile/main_test.go
index 5566018..af48f3b 100644
--- a/cmd/transpile/main_test.go
+++ b/cmd/transpile/main_test.go
@@ -5,6 +5,7 @@ import (
 	"bytes"
 	"encoding/json"
 	"io/ioutil"
+	"strings"
 	"testing"
 
 	"github.com/dirtbags/moth/pkg/transpile"
@@ -163,3 +164,22 @@ func TestMothballs(t *testing.T) {
 		}
 	}
 }
+
+func TestFilesystem(t *testing.T) {
+	stdout := new(bytes.Buffer)
+	stderr := new(bytes.Buffer)
+	tp := T{
+		Stdout: stdout,
+		Stderr: stderr,
+		BaseFs: afero.NewOsFs(),
+	}
+
+	stdout.Reset()
+	if err := tp.Run("file", "-dir=testdata/cat1/1", "-file=moo.txt"); err != nil {
+		t.Error(err)
+	}
+	if !strings.Contains(stdout.String(), "Moo.") {
+		t.Error("Wrong file pulled", stdout.String())
+	}
+
+}
\ No newline at end of file
diff --git a/cmd/transpile/testdata/cat1/1/mkpuzzle b/cmd/transpile/testdata/cat1/1/mkpuzzle
new file mode 100755
index 0000000..e61b4a2
--- /dev/null
+++ b/cmd/transpile/testdata/cat1/1/mkpuzzle
@@ -0,0 +1,38 @@
+#! /bin/sh
+
+fail () {
+    echo "ERROR: $*" 1>&2
+    exit 1
+}
+
+case $1:$2 in
+    puzzle:)
+        cat <<'EOT'
+{
+    "Answers": ["answer"],
+    "Pre": {
+        "Authors": ["neale"],
+        "Body": "I am a generated puzzle."
+    }
+}
+EOT
+        ;;
+    file:moo.txt)
+        echo "Moo."
+        ;;
+    file:*)
+        cat "$2" || exit 1
+        ;;
+    answer:moo)
+        echo '{"Correct":true}'
+        ;;
+    answer:error)
+        fail "you requested an error"
+        ;;
+    answer:*)
+        echo '{"Correct":false}'
+        ;;
+    *)
+        fail "What is $1"
+        ;;
+esac
diff --git a/cmd/transpile/testdata/cat1/1/moo.txt b/cmd/transpile/testdata/cat1/1/moo.txt
new file mode 100644
index 0000000..b4e62b9
--- /dev/null
+++ b/cmd/transpile/testdata/cat1/1/moo.txt
@@ -0,0 +1,8 @@
+ ______
+< moo. >
+ ------
+        \   ^__^
+         \  (oo)\_______
+            (__)\       )\/\
+                ||----w |
+                ||     ||