diff --git a/focker/export.py b/focker/export.py
new file mode 100644
index 0000000..93912a9
--- /dev/null
+++ b/focker/export.py
@@ -0,0 +1,81 @@
+from tarfile import TarFile, \
+    TarInfo
+import os
+import stat
+from itertools import chain
+from .misc import filehash
+
+
+def normalized_recursive_directory_iterator(path):
+    Q = iter([ path ])
+    name = next(Q, None)
+    while name:
+        st = os.lstat(name)
+        if stat.S_ISDIR(st.st_mode):
+            L = sorted(os.listdir(name))
+            def create_map(name, L):
+                return map(lambda x: os.path.join(name, x), L)
+            L = create_map(name, L)
+            yield (os.path.relpath(name, path), name, st.st_mode, st.st_uid, st.st_gid, st.st_size)
+            Q = chain(L, Q)
+        else: # file
+            yield (os.path.relpath(name, path), name, st.st_mode, st.st_uid, st.st_gid, st.st_size)
+        name = next(Q, None)
+
+
+def _export_diff(mountpoint, origin_mountpoint, output_directory):
+
+    mit = normalized_recursive_directory_iterator(mountpoint)
+    oit = normalized_recursive_directory_iterator(origin_mountpoint)
+
+    def emit_removal(o):
+        print('Removal:', o[0])
+
+    def emit_creation(m):
+        print('Creation:', m[0])
+
+    def emit_compare(m, o):
+        if m[2] != o[2] or m[3] != o[3] or m[4] != o[4]:
+            print('Metadata change:', o[0])
+        elif m[5] != o[5] :
+            print('Size change:', o[0])
+        elif stat.S_ISREG(m[2]) and filehash(m[1]) != filehash(o[1]):
+            print('Content change:', o[0])
+        else: # no change
+            pass # print('Compare:', m[0])
+
+    m = next(mit, None)
+    o = next(oit, None)
+    while True:
+        if m is None and o is None:
+            break
+        elif m is None and o is not None:
+            emit_removal(o)
+        elif m is not None and o is None:
+            emit_creation(m)
+        elif m[0] < o[0]:
+            emit_creation(m)
+            m = next(mit, None)
+        elif m[0] > o[0]:
+            emit_removal(o)
+            o = next(oit, None)
+        else:
+            emit_compare(m, o)
+            m = next(mit, None)
+            o = next(oit, None)
+
+    #for root, dirs, files in os.walk(path):
+     #  dirs.sort()
+      # for dirname in dirs:
+        #    print(os.path.join(root, dirname))
+
+
+def command_export(args):
+    name, _ = zfs_find(args.reference, focker_type='image')
+    mountpoint = zfs_mountpoint(name)
+    origin = zfs_parse_output(['zfs', 'get', '-H', 'origin', name])
+    origin = origin[2].split('@')[0]
+    origin_mountpoint = zfs_mountpoint(origin)
+    Q = [ zfs_mountpoint(name) ]
+    while len(Q) > 0:
+        el = Q.pop()
diff --git a/focker/misc.py b/focker/misc.py
index 8122106..cc2a21f 100644
--- a/focker/misc.py
+++ b/focker/misc.py
@@ -9,6 +9,19 @@ import random
 from .zfs import zfs_exists
 import os
 import fcntl
+import hashlib
+
+
+def filehash(fname):
+    h = hashlib.sha256()
+    with open(fname, 'rb') as f:
+        while True:
+            data = f.read(1024*1024*4)
+            if not data:
+                break
+            h.update(data)
+    res = h.hexdigest()
+    return res
 
 
 def random_sha256_hexdigest():
diff --git a/focker/steps.py b/focker/steps.py
index e01c195..dfc53dc 100644
--- a/focker/steps.py
+++ b/focker/steps.py
@@ -11,18 +11,7 @@ from .jail import jail_run
 import shutil
 import os
 import shlex
-
-
-def filehash(fname):
-    h = hashlib.sha256()
-    with open(fname, 'rb') as f:
-        while True:
-            data = f.read(1024*1024*4)
-            if not data:
-                break
-            h.update(data)
-    res = h.hexdigest()
-    return res
+from .misc import filehash
 
 
 class RunStep(object):