diff --git a/__main__.py b/__main__.py
index a0ac1c5..0f73041 100755
--- a/__main__.py
+++ b/__main__.py
@@ -2,7 +2,7 @@
 
 import os
 
-import file
+import fs
 
 
 if __name__ == '__main__':
@@ -11,8 +11,8 @@ if __name__ == '__main__':
     directory_path = os.path.join(root_path, 'tmp')
     file_path = os.path.join(directory_path, 'file')
 
-    file.wipe(directory_path)
-    file.make(directory_path)
-    file.write(file_path, 'Martine écrit beaucoup.')
-    file.empty(file_path)
-    file.write(file_path, 'Martine écrit moins.')
+    fs.wipe(directory_path)
+    fs.make_directory(directory_path)
+    fs.write(file_path, 'Martine écrit beaucoup.')
+    fs.empty_file(file_path)
+    fs.write(file_path, 'Martine écrit moins.')
diff --git a/arg/__init__.py b/arg/__init__.py
new file mode 100644
index 0000000..5db26ae
--- /dev/null
+++ b/arg/__init__.py
@@ -0,0 +1,5 @@
+import sys
+
+
+def split() -> tuple[str, list[str]]:
+    return sys.argv[0], sys.argv[1:]
diff --git a/file/__init__.py b/file/__init__.py
deleted file mode 100644
index eaf0059..0000000
--- a/file/__init__.py
+++ /dev/null
@@ -1,37 +0,0 @@
-import os
-import shutil
-import subprocess
-
-CHARSET = 'UTF-8'
-
-
-def create_image(file_path: str, size_bytes: int):
-    subprocess.run([
-        'qemu-img',
-        'create',
-        '-f', 'qcow2',
-        file_path,
-        size_bytes,
-    ])
-
-
-def empty(file_path: str):
-    write(file_path, str())
-
-
-def make(directory_path: str):
-    os.makedirs(directory_path, exist_ok=True)
-
-
-def wipe(path: str):
-    try:
-        shutil.rmtree(path)
-    except NotADirectoryError:
-        os.remove(path)
-    except FileNotFoundError:
-        pass
-
-
-def write(file_path: str, text: str, charset=CHARSET):
-    with open(file_path, 'bw') as file_object:
-        file_object.write(text.encode(charset))
diff --git a/fs/__init__.py b/fs/__init__.py
new file mode 100644
index 0000000..73dd8f0
--- /dev/null
+++ b/fs/__init__.py
@@ -0,0 +1,71 @@
+import os
+import shutil
+import subprocess
+
+from .. import ps
+
+CHARSET = 'UTF-8'
+
+
+def create_image(file_path: str, size_bytes: int):
+    ps.run(
+        ('qemu-img', 'create'),
+        ('-f', 'qcow2'),
+        (file_path, size_bytes),
+    )
+
+
+def empty_file(path: str):
+    write(path, str())
+
+
+def get_mount_uuid(path: str):
+    return ps.run_line(
+        ('findmnt'),
+        ('--noheadings'),
+        ('--output', 'UUID'),
+        (path),
+    )
+
+
+def get_path_mount(path: str):
+    return ps.run_line(
+        ('stat'),
+        ('--format', '%m'),
+        (path),
+    )
+
+
+def get_path_uuid(path: str):
+    return get_mount_uuid(get_path_mount(path))
+
+
+def make_directory(path: str):
+    os.makedirs(path, exist_ok=True)
+
+
+def read_file(file_path: str):
+    with open(file_path, 'br') as file_object:
+        return file_object.read()
+
+
+def read_file_lines(file_path: str, charset=CHARSET):
+    return read_file_text(file_path).split(os.linesep)
+
+
+def read_file_text(file_path: str, charset=CHARSET):
+    return read_file(file_path).decode(charset)
+
+
+def wipe(path: str):
+    try:
+        shutil.rmtree(path)
+    except NotADirectoryError:
+        os.remove(path)
+    except FileNotFoundError:
+        pass
+
+
+def write(file_path: str, text: str, charset=CHARSET):
+    with open(file_path, 'bw') as file_object:
+        file_object.write(text.encode(charset))
diff --git a/grub/__init__.py b/grub/__init__.py
new file mode 100644
index 0000000..5c5f977
--- /dev/null
+++ b/grub/__init__.py
@@ -0,0 +1,30 @@
+from .. import ps
+
+COMPRESSION = 'xz'
+ENV_BYTES = 1024
+ENV_COMMENT = '#'
+ENV_HEADER = f'''{ENV_COMMENT} GRUB Environment Block
+'''
+MODULES = {
+    'i386-pc': [
+        ('biosdisk'),
+        ('ntldr'),
+    ]
+}
+
+
+def make_image(image_format: str, image_path: str, modules: list[str],
+               memdisk_path: str, pubkey_path: str=None) -> None:
+    args = [
+        ('grub-mkimage'),
+        ('--compress', COMPRESSION),
+        ('--format', image_format),
+        ('--output', image_path),
+        ('--memdisk', memdisk_path),
+    ]
+    if pubkey_path:
+        args.append(('--pubkey', pubkey_path))
+    args.extend(modules)
+    if modules := MODULES.get(image_format, None):
+        args.extend(modules)
+    ps.run(*args)
diff --git a/project/__init__.py b/project/__init__.py
new file mode 100644
index 0000000..b03f2c4
--- /dev/null
+++ b/project/__init__.py
@@ -0,0 +1,13 @@
+import os
+
+
+class Project:
+
+    def __init__(self, root_path: str):
+        self.root = root_path
+
+
+def from_root_file(file_path: str):
+    project_file = os.path.realpath(file_path)
+    project_root = os.path.dirname(project_file)
+    return Project(real_file)
diff --git a/ps/__init__.py b/ps/__init__.py
new file mode 100644
index 0000000..ddbfb72
--- /dev/null
+++ b/ps/__init__.py
@@ -0,0 +1,28 @@
+import subprocess
+
+from .. import txt
+
+
+def get_tuples_args(tuples) -> list[str]:
+    args = []
+    for item in tuples:
+        if type(item) is tuple:
+            args.extend(item)
+        else:
+            args.append(item)
+    return args
+
+
+def run(*tuples) -> subprocess.CompletedProcess:
+    return subprocess.run(get_tuples_args(tuples), capture_output=False)
+
+
+def run_line(*tuples, charset:str=txt.CHARSET) -> str:
+    lines = run_lines(*get_tuples_args(tuples), charset=charset)
+    return lines[0]
+
+
+def run_lines(*tuples, charset:str=txt.CHARSET) -> list[str]:
+    process = subprocess.run(get_tuples_args(tuples), capture_output=True)
+    string = process.stdout.decode(charset)
+    return string.rstrip().splitlines()
diff --git a/txt/__init__.py b/txt/__init__.py
new file mode 100644
index 0000000..81903f4
--- /dev/null
+++ b/txt/__init__.py
@@ -0,0 +1 @@
+CHARSET='UTF-8'