diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..bee8a64
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+__pycache__
diff --git a/focker.py b/focker.py
index 88f10e5..c6649f0 100644
--- a/focker.py
+++ b/focker.py
@@ -1,58 +1,31 @@
 from argparse import ArgumentParser
 import yaml
 import os
-from weir import zfs, process
-from .build import build
+# from weir import zfs, process
+from .image import command_image_build
+import sys
+from .zfs import zfs_init
 
 
-def clone(self, name, props={}, force=False):
-    url = zfs._urlsplit(self.name)
-    url_1 = zfs._urlsplit(name)
-    if url.netloc != url_1.netloc:
-        raise ValueError('Clone has to happen on the same host')
-    cmd = ['zfs', 'clone']
-    for prop, value in props.items():
-        cmd.append('-o')
-        cmd.append(prop + '=' + str(value))
-    cmd.append(url.path)
-    cmd.append(url_1.path)
-    process.check_call(cmd, netloc=url.netloc)
-
-zfs.ZFSSnapshot.clone = clone
-
-
-def command_build(args):
-    fname = os.path.join(args.focker_dir, 'Fockerfile.yml')
-    print('fname:', fname)
-    if not os.path.exists(fname):
-        raise ValueError('No Fockerfile.yml could be found in the specified directory')
-    with open(fname, 'r') as f:
-        spec = yaml.safe_load(f)
-    print('spec:', spec)
-    build(spec)
-
+def create_parser():
+    parser_top = ArgumentParser()
+    subparsers_top = parser_top.add_subparsers()
 
-def run(args):
-    pass
+    subparsers = subparsers_top.add_parser('image').add_subparsers()
+    parser = subparsers.add_parser('build')
+    parser.set_defaults(func=command_image_build)
+    parser.add_argument('focker_dir', type=str)
 
+    return parser_top
 
-def create_parser():
-    parser = ArgumentParser()
-    subparsers = parser.add_subparsers()
-    parser_build = subparsers.add_parser('build')
-    parser_build.set_defaults(func=command_build)
-    parser_build.add_argument('focker_dir', type=str)
-    parser_run = subparsers.add_parser('run')
-    parser_run.set_defaults(func=run)
-    parser_rm = subparsers.add_parser('rm')
-    parser_rmi = subparsers.add_parser('rmi')
-    parser_ps = subparsers.add_parser('ps')
-    parser_images = subparsers.add_parser('images')
-    return parser
 
+def main():
+    zfs_init()
+    parser = create_parser()
+    args = parser.parse_args()
+    if not hasattr(args, 'func'):
+        sys.exit('You must choose a mode')
+    args.func(args)
 
-parser = create_parser()
-args = parser.parse_args()
-if not hasattr(args, 'func'):
-    raise ValueError('You must choose the mode')
-args.func(args)
+if __name__ == '__main__':
+    main()
diff --git a/build.py b/image.py
similarity index 50%
rename from build.py
rename to image.py
index 6812e5d..66957fc 100644
--- a/build.py
+++ b/image.py
@@ -1,4 +1,6 @@
 from .zfs import *
+import os
+import yaml
 
 
 def process_step(step, name):
@@ -17,8 +19,19 @@ def process_steps(steps, name):
 def build(spec):
     if 'base' not in spec:
         raise ValueError('Missing base specification')
-    base = spec.base
-    base = zfs_snapshot_by_tag_or_name(base)
+    base = spec['base']
+    base = zfs_snapshot_by_tag_or_sha256(base)
 
     root = '/'.join(base.split('/')[:-1])
     print('base:', base, 'root:', root)
+
+
+def command_image_build(args):
+    fname = os.path.join(args.focker_dir, 'Fockerfile')
+    print('fname:', fname)
+    if not os.path.exists(fname):
+        raise ValueError('No Fockerfile could be found in the specified directory')
+    with open(fname, 'r') as f:
+        spec = yaml.safe_load(f)
+    print('spec:', spec)
+    build(spec)
diff --git a/run.py b/run.py
new file mode 100644
index 0000000..e69de29
diff --git a/zfs.py b/zfs.py
index f35576d..a7fe91d 100644
--- a/zfs.py
+++ b/zfs.py
@@ -1,10 +1,12 @@
 import subprocess
 import csv
 import io
+import os
 
 
 def zfs_run(command):
-    out = subprocess.check_output(command)
+    # print('Running:', command)
+    out = subprocess.check_output(command, stderr=subprocess.STDOUT)
     return out
 
 
@@ -20,15 +22,42 @@ def zfs_get_type(name):
     return lst[0][1]
 
 
-def zfs_snapshot_by_tag_or_name(s):
-    lst = zfs_parse_output(['zfs', 'list', '-o', 'name,focker:tags,type', '-H'])
-    lst = list(filter(lambda a: (a[0] == s or s in a[1].split(' ') and a[2] == 'snapshot')))
+def zfs_snapshot_by_tag_or_sha256(s):
+    lst = zfs_parse_output(['zfs', 'list', '-o', 'focker:sha256,focker:tags,type,name', '-H', '-t', 'snapshot'])
+    lst = list(filter(lambda a: (a[0] == s or s in a[1].split(' ')) and a[2] == 'snapshot', lst))
     if len(lst) == 0:
         raise ValueError('Reference not found: ' + s)
     if len(lst) > 1:
         raise ValueError('Ambiguous reference: ' + s)
-    return lst[0][0]
+    return lst[0][3]
 
 
 def zfs_clone(name, target_name):
     zfs_run(['zfs', 'clone', name, target_name])
+
+
+def zfs_exists(name):
+    try:
+        zfs_run(['zfs', 'list', name])
+    except subprocess.CalledProcessError as e:
+        return False
+    return True
+
+
+def zfs_init():
+    poolname = zfs_parse_output(['zfs', 'list', '-H', '/'])
+    if len(poolname) == 0:
+        raise ValueError('Not a ZFS root')
+    poolname = poolname[0][0].split('/')[0]
+    print('poolname:', poolname)
+    for path in ['/focker', '/focker/images', '/focker/volumes', '/focker/jails']:
+        if not os.path.exists(path):
+            os.mkdir(path)
+    if not zfs_exists(poolname + '/focker'):
+        zfs_run(['zfs', 'create', '-o', 'canmount=off', '-o', 'mountpoint=/focker', poolname + '/focker'])
+    if not zfs_exists(poolname + '/focker/images'):
+        zfs_run(['zfs', 'create', '-o', 'canmount=off', poolname + '/focker/images'])
+    if not zfs_exists(poolname + '/focker/volumes'):
+        zfs_run(['zfs', 'create', '-o', 'canmount=off', poolname + '/focker/volumes'])
+    if not zfs_exists(poolname + '/focker/volumes'):
+        zfs_run(['zfs', 'create', '-o', 'canmount=off', poolname + '/focker/jails'])