diff --git a/negromate/web/builder.py b/negromate/web/builder.py
index 3ad4e5f..6ae61d5 100644
--- a/negromate/web/builder.py
+++ b/negromate/web/builder.py
@@ -8,7 +8,7 @@ from jinja2 import Environment, PackageLoader, select_autoescape
 from jinja2.utils import Markup
 import srt
 
-from negromate.songs import load_songs
+from negromate.songs.loader import load_songs
 
 from .karaoke_templates import update_karaoke_songs
 
diff --git a/negromate/web/commands.py b/negromate/web/commands.py
deleted file mode 100644
index b962667..0000000
--- a/negromate/web/commands.py
+++ /dev/null
@@ -1,11 +0,0 @@
-from pathlib import Path
-
-from .builder import Builder
-
-
-def build():
-    builder = Builder(
-        Path(sys.argv[1]),
-        Path(sys.argv[2]),
-    )
-    builder.build()
diff --git a/negromate/web/commands/__init__.py b/negromate/web/commands/__init__.py
new file mode 100644
index 0000000..6edaad3
--- /dev/null
+++ b/negromate/web/commands/__init__.py
@@ -0,0 +1,38 @@
+import argparse
+import sys
+
+from . import run, build, thumbnail
+
+
+def main():
+    """
+        Build parser for all the commands and launch appropiate command.
+
+        Each command must be a module with at least the following members:
+
+            * name: String with the command name. Will be used for
+              argparse subcommand.
+            * help_text: String with the help text.
+            * options: Function to build the parser of the command. Takes
+              one parametter, the argparser parser instance for this
+              subcommand.
+            * run: Function that runs the actual command. Takes one
+              parametter, the Namespace with the arguments.
+    """
+    commands = [
+        build,
+        run,
+        thumbnail,
+    ]
+
+    parser = argparse.ArgumentParser()
+    subparsers = parser.add_subparsers()
+    for command in commands:
+        command_parser = subparsers.add_parser(command.name, help=command.help_text)
+        command_parser.set_defaults(command=command.name)
+        command.options(command_parser)
+
+    args = parser.parse_args()
+    for command in commands:
+        if args.command == command.name:
+            command.run(args)
diff --git a/negromate/web/commands/build.py b/negromate/web/commands/build.py
new file mode 100644
index 0000000..eddaf88
--- /dev/null
+++ b/negromate/web/commands/build.py
@@ -0,0 +1,21 @@
+from pathlib import Path
+from ..builder import Builder
+
+
+name = 'build'
+help_text = 'Generate static website'
+
+
+def options(parser):
+    parser.add_argument(
+        'song_folder', help="Folder with the song database.")
+    parser.add_argument(
+        'lyrics_file', help="File with the lyrics of the songs.")
+
+
+def run(args):
+    builder = Builder(
+        Path(args.song_folder),
+        Path(args.lyrics_file),
+    )
+    builder.build()
diff --git a/negromate/web/commands/run.py b/negromate/web/commands/run.py
new file mode 100644
index 0000000..6bf76f5
--- /dev/null
+++ b/negromate/web/commands/run.py
@@ -0,0 +1,26 @@
+from http.server import test, SimpleHTTPRequestHandler
+from functools import partial
+
+
+name = 'run'
+help_text = 'Start web server to test the website'
+
+
+def options(parser):
+    parser.add_argument(
+        'song_folder', help="Folder with the song database.")
+    parser.add_argument(
+        'port', action='store', default=8000, type=int, nargs='?',
+        help='Specify alternate port [default: 8000]')
+    parser.add_argument(
+        '--bind', '-b', default='', metavar='ADDRESS',
+        help='Specify alternate bind address [default: all interfaces]')
+
+
+def run(args):
+    Handler = partial(
+        SimpleHTTPRequestHandler,
+        directory=args.song_folder,
+    )
+
+    test(HandlerClass=Handler, port=args.port, bind=args.bind)
diff --git a/negromate/web/commands/thumbnail.py b/negromate/web/commands/thumbnail.py
new file mode 100644
index 0000000..10e381d
--- /dev/null
+++ b/negromate/web/commands/thumbnail.py
@@ -0,0 +1,23 @@
+import subprocess
+from pathlib import Path
+
+from negromate.songs.utils import generate_cover, generate_thumbnail
+
+name = 'thumbnail'
+help_text = 'Generate cover and thumbnail for a video.'
+
+
+def options(parser):
+    parser.add_argument(
+        'video', help="Video of the song.", type=Path)
+    parser.add_argument(
+        'second', type=int,
+        help='Take snapshot at this second.')
+
+
+def run(args):
+    video = args.video
+    cover = video.parent / 'cover.jpg'
+    thumbnail = video.parent / 'thumb.jpg'
+    generate_cover(video, cover, args.second)
+    generate_thumbnail(cover, thumbnail)