diff --git a/.gitignore b/.gitignore
index 90c0433..4909e08 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,5 @@
 __pycache__
 /tmp
-/.idea
+/.venv
+/.vscode
 /dist
diff --git a/pyproject.toml b/pyproject.toml
index ac386d1..756a434 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,32 +1,39 @@
 [build-system]
-requires = ['hatchling']
-build-backend = 'hatchling.build'
+requires = ["hatchling"]
+build-backend = "hatchling.build"
 
 [project]
 authors = [
-    { name = 'Marc Beninca', email = 'git@marc.beninca.link' },
+    { name = "Marc Beninca", email = "git@marc.beninca.link" },
 ]
 maintainers = [
-    { name = 'Marc Beninca', email = 'git@marc.beninca.link' },
+    { name = "Marc Beninca", email = "git@marc.beninca.link" },
 ]
 classifiers = [
-    'Programming Language :: Python :: 3',
-    'License :: OSI Approved :: GNU Affero General Public License v3',
-    'Operating System :: OS Independent',
+    "Programming Language :: Python :: 3",
+    "License :: OSI Approved :: GNU Affero General Public License v3",
+    "Operating System :: OS Independent",
 ]
 dependencies = []
-description = 'Read Write eXecute'
-dynamic = ['version']
+description = "Read Write eXecute"
+dynamic = ["version"]
 keywords = []
-license-files = { paths = ['license.md'] }
-name = 'rwx'
-readme = 'readme.md'
-requires-python = '>= 3.10'
+license-files = { paths = ["license.md"] }
+name = "rwx"
+readme = "readme.md"
+requires-python = ">= 3.11"
 
 [project.scripts]
-# command = 'package.module:function'
+# command = "package.module:function"
 
 [project.urls]
 
 [tool.hatch.version]
-path = 'rwx/__init__.py'
+path = "rwx/__init__.py"
+
+[tool.ruff]
+line-length = 80
+
+[tool.ruff.lint]
+ignore = ["COM812", "D203", "D213", "ISC001"]
+select = ["ALL"]
diff --git a/rwx/__init__.py b/rwx/__init__.py
index b8023d8..a1c5ee6 100644
--- a/rwx/__init__.py
+++ b/rwx/__init__.py
@@ -1 +1,3 @@
-__version__ = '0.0.1'
+"""Read Write eXecute."""
+
+__version__ = "0.0.1"
diff --git a/rwx/__main__.py b/rwx/__main__.py
index 0f73041..f6276e4 100755
--- a/rwx/__main__.py
+++ b/rwx/__main__.py
@@ -1,18 +1,19 @@
 #! /usr/bin/env python3
 
-import os
+"""Entry point."""
+
+from pathlib import Path
 
 import fs
 
-
-if __name__ == '__main__':
-    file_path = os.path.realpath(__file__)
-    root_path = os.path.dirname(file_path)
-    directory_path = os.path.join(root_path, 'tmp')
-    file_path = os.path.join(directory_path, 'file')
+if __name__ == "__main__":
+    file_path = Path(__file__).resolve()
+    root_path = file_path.parent
+    directory_path = root_path / "tmp"
+    file_path = directory_path / "file"
 
     fs.wipe(directory_path)
     fs.make_directory(directory_path)
-    fs.write(file_path, 'Martine écrit beaucoup.')
+    fs.write(file_path, "Martine écrit beaucoup.")
     fs.empty_file(file_path)
-    fs.write(file_path, 'Martine écrit moins.')
+    fs.write(file_path, "Martine écrit moins.")
diff --git a/rwx/arg/__init__.py b/rwx/arg/__init__.py
index aa6e4b8..71ce0a7 100644
--- a/rwx/arg/__init__.py
+++ b/rwx/arg/__init__.py
@@ -1,6 +1,9 @@
+"""Handle system arguments."""
+
 import sys
 
 
 def split() -> tuple[str, list[str]]:
+    """Split command & actual arguments."""
     command, *arguments = sys.argv
     return command, arguments
diff --git a/rwx/cmd/__init__.py b/rwx/cmd/__init__.py
index 9403d24..e3b75bc 100644
--- a/rwx/cmd/__init__.py
+++ b/rwx/cmd/__init__.py
@@ -1,15 +1,17 @@
+"""Handle system commands & packages."""
+
 commands: list[str] = []
 packages: list[str] = []
 
 
 def need(command: str) -> None:
+    """Assert package dependency for a command."""
     match command:
-        case 'debootstrap':
-            package = 'debootstrap'
-        case 'mksquashfs' | 'unsquashfs':
-            package = 'squashfs-tools'
+        case "debootstrap":
+            package = "debootstrap"
+        case "mksquashfs" | "unsquashfs":
+            package = "squashfs-tools"
         case _:
             package = None
-    if package:
-        if package not in packages:
-            packages.append(package)
+    if package and package not in packages:
+        packages.append(package)
diff --git a/rwx/cmd/squashfs/__init__.py b/rwx/cmd/squashfs/__init__.py
index 637890a..322186c 100644
--- a/rwx/cmd/squashfs/__init__.py
+++ b/rwx/cmd/squashfs/__init__.py
@@ -1,14 +1,19 @@
 import ps
+
 import rwx.cmd
 
-rwx.cmd.need('mksquashfs')
+rwx.cmd.need("mksquashfs")
 
 
 def mksquashfs(input_root: str, output_file: str):
-    ps.run([
-        'mksquashfs',
-        input_root,
-        output_file,
-        '-comp', 'zstd',
-        '-Xcompression-level', str(18),
-    ])
+    ps.run(
+        [
+            "mksquashfs",
+            input_root,
+            output_file,
+            "-comp",
+            "zstd",
+            "-Xcompression-level",
+            str(18),
+        ]
+    )
diff --git a/rwx/deb/__init__.py b/rwx/deb/__init__.py
index a773123..e9c6a9e 100644
--- a/rwx/deb/__init__.py
+++ b/rwx/deb/__init__.py
@@ -1,20 +1,20 @@
 import cmd
+
 import ps
 
-cmd.need('debootstrap')
+cmd.need("debootstrap")
 
-BOOTSTRAP_ARCHITECTURE = 'amd64'
-BOOTSTRAP_VARIANT = 'minbase'
+BOOTSTRAP_ARCHITECTURE = "amd64"
+BOOTSTRAP_VARIANT = "minbase"
 
 
 def bootstrap(root_path: str, suite: str, mirror_location: str):
     command = [
-        ('debootstrap',),
-        ('--arch', BOOTSTRAP_ARCHITECTURE),
-        ('--variant', BOOTSTRAP_VARIANT),
+        ("debootstrap",),
+        ("--arch", BOOTSTRAP_ARCHITECTURE),
+        ("--variant", BOOTSTRAP_VARIANT),
         (suite,),
         (root_path,),
         (mirror_location,),
     ]
-    completed_process = ps.run(command)
-    return completed_process
+    return ps.run(command)
diff --git a/rwx/err/__init__.py b/rwx/err/__init__.py
new file mode 100644
index 0000000..b996913
--- /dev/null
+++ b/rwx/err/__init__.py
@@ -0,0 +1,2 @@
+class Exception(Exception):
+    pass
diff --git a/rwx/fs/__init__.py b/rwx/fs/__init__.py
index ecaebf0..c91e0b8 100644
--- a/rwx/fs/__init__.py
+++ b/rwx/fs/__init__.py
@@ -1,36 +1,41 @@
+"""Operations involving FileSystems."""
+
 import os
 import shutil
 
 from rwx import ps
 
-CHARSET = 'UTF-8'
+CHARSET = "UTF-8"
 
 
-def create_image(file_path: str, size_bytes: int):
+def create_image(file_path: str, size_bytes: int) -> None:
+    """Create a virtual device image file."""
     ps.run(
-        ('qemu-img', 'create'),
-        ('-f', 'qcow2'),
+        ("qemu-img", "create"),
+        ("-f", "qcow2"),
         (file_path, size_bytes),
     )
 
 
-def empty_file(path: str):
-    write(path, str())
+def empty_file(path: str) -> None:
+    """Empty the file at provided path."""
+    write(path, "")
 
 
-def get_mount_uuid(path: str):
+def get_mount_uuid(path: str) -> str:
+    """Return the UUID of provided mountpoint path."""
     return ps.run_line(
-        ('findmnt',),
-        ('--noheadings',),
-        ('--output', 'UUID'),
+        ("findmnt",),
+        ("--noheadings",),
+        ("--output", "UUID"),
         (path,),
     )
 
 
 def get_path_mount(path: str):
     return ps.run_line(
-        ('stat',),
-        ('--format', '%m'),
+        ("stat",),
+        ("--format", "%m"),
         (path,),
     )
 
@@ -44,7 +49,7 @@ def make_directory(path: str):
 
 
 def read_file(file_path: str):
-    with open(file_path, 'br') as file_object:
+    with open(file_path, "br") as file_object:
         return file_object.read()
 
 
@@ -66,5 +71,5 @@ def wipe(path: str):
 
 
 def write(file_path: str, text: str, charset=CHARSET):
-    with open(file_path, 'bw') as file_object:
+    with open(file_path, "bw") as file_object:
         file_object.write(text.encode(charset))
diff --git a/rwx/grub/__init__.py b/rwx/grub/__init__.py
index b931ee3..cd016ab 100644
--- a/rwx/grub/__init__.py
+++ b/rwx/grub/__init__.py
@@ -1,33 +1,39 @@
 import cmd
+
 import ps
 
-cmd.need('grub-mkimage')
+cmd.need("grub-mkimage")
 
-COMPRESSION = 'xz'
+COMPRESSION = "xz"
 ENV_BYTES = 1024
-ENV_COMMENT = '#'
-ENV_HEADER = f'''{ENV_COMMENT} GRUB Environment Block
-'''
+ENV_COMMENT = "#"
+ENV_HEADER = f"""{ENV_COMMENT} GRUB Environment Block
+"""
 MODULES = {
-    'i386-pc': [
-        ('biosdisk',),
-        ('ntldr',),
-    ]
+    "i386-pc": [
+        ("biosdisk",),
+        ("ntldr",),
+    ],
 }
 
 
-def make_image(image_format: str, image_path: str, modules: list[str],
-               memdisk_path: str, pubkey_path: str = None) -> None:
+def make_image(
+    image_format: str,
+    image_path: str,
+    modules: list[str],
+    memdisk_path: str,
+    pubkey_path: str | None = None,
+) -> None:
     args = [
-        ('grub-mkimage',),
-        ('--compress', COMPRESSION),
-        ('--format', image_format),
-        ('--output', image_path),
-        ('--memdisk', memdisk_path),
+        ("grub-mkimage",),
+        ("--compress", COMPRESSION),
+        ("--format", image_format),
+        ("--output", image_path),
+        ("--memdisk", memdisk_path),
     ]
     if pubkey_path:
-        args.append(('--pubkey', pubkey_path))
+        args.append(("--pubkey", pubkey_path))
     args.extend(modules)
-    if modules := MODULES.get(image_format, None):
+    if modules := MODULES.get(image_format):
         args.extend(modules)
     ps.run(*args)
diff --git a/rwx/log/__init__.py b/rwx/log/__init__.py
index 2cf0b09..50048e5 100644
--- a/rwx/log/__init__.py
+++ b/rwx/log/__init__.py
@@ -2,21 +2,31 @@ import logging
 import sys
 
 
-def get_logger(name: str) -> logging.Logger:
+def get_file_logger(name: str) -> logging.Logger:
     formatter = logging.Formatter(
-        "%(name)s: %(asctime)s | %(levelname)s | %(filename)s:%(lineno)s | %(process)d >>> %(message)s"
+        "%(name)s: %(asctime)s | %(levelname)s | %(filename)s:%(lineno)s | %(process)d >>> %(message)s",
     )
-
-    # file_handler = logging.FileHandler('log.txt')
-    # file_handler.setFormatter(formatter)
-    # file_handler.setLevel(logging.INFO)
-
+    #
     out_handler = logging.StreamHandler(stream=sys.stdout)
     out_handler.setFormatter(formatter)
     out_handler.setLevel(logging.INFO)
-
+    #
     logger = logging.getLogger(name)
-    # logger.addHandler(file_handler)
     logger.addHandler(out_handler)
     logger.setLevel(logging.INFO)
+    #
     return logger
+
+
+def get_stream_logger(level: int) -> logging.Logger:
+    out_handler = logging.StreamHandler(stream=sys.stdout)
+    out_handler.setLevel(level)
+    #
+    logger = logging.getLogger()
+    logger.addHandler(out_handler)
+    logger.setLevel(level)
+    #
+    return logger
+
+
+stream = get_stream_logger(logging.INFO)
diff --git a/rwx/prj/__init__.py b/rwx/prj/__init__.py
index f0a2fe5..227a686 100644
--- a/rwx/prj/__init__.py
+++ b/rwx/prj/__init__.py
@@ -2,7 +2,7 @@ from os import path
 
 
 class Project:
-    def __init__(self, file_path: str):
+    def __init__(self, file_path: str) -> None:
         self.file: str = path.realpath(file_path)
         self.root: str = path.dirname(self.file)
         self.name: str = path.basename(self.root)
diff --git a/rwx/prj/sphinx.py b/rwx/prj/sphinx.py
index 4da1ebf..afa0901 100644
--- a/rwx/prj/sphinx.py
+++ b/rwx/prj/sphinx.py
@@ -1,4 +1,7 @@
+"""Project consisting only of a Sphinx documentation."""
+
 from os import path
+
 from sphinx.cmd.build import build_main
 
 from rwx.fs import wipe
@@ -6,22 +9,28 @@ from rwx.prj import Project
 
 
 class SphinxProject(Project):
-    def __init__(self, file_path: str):
+    def __init__(self, file_path: str) -> None:
         super().__init__(file_path)
 
-    def build(self):
-        output_root: str = path.join(self.root, 'out')
+    def build(self) -> None:
+        output_root: str = path.join(self.root, "out")
         wipe(output_root)
         arguments: list[str] = [
             "-E",
-            "-j", "2",
-            "-b", "html",
-            "-D", f"project={self.name}",
-            "-D", "master_doc={}".format("index"),
-            "-D", "html_theme={}".format("sphinx_rtd_theme"),
-            "-c", self.root,
+            "-j",
+            "2",
+            "-b",
+            "html",
+            "-D",
+            f"project={self.name}",
+            "-D",
+            "master_doc={}".format("index"),
+            "-D",
+            "html_theme={}".format("sphinx_rtd_theme"),
+            "-c",
+            self.root,
             # "-C",
             path.join(self.root, self.name),
-            path.join(output_root, self.name),
+            path.join(output_root, "web"),
         ]
         build_main(arguments)
diff --git a/rwx/ps/__init__.py b/rwx/ps/__init__.py
index 5b50456..b66c21b 100644
--- a/rwx/ps/__init__.py
+++ b/rwx/ps/__init__.py
@@ -14,7 +14,9 @@ def get_tuples_args(tuples) -> list[str]:
 
 
 def run(*tuples) -> subprocess.CompletedProcess:
-    return subprocess.run(get_tuples_args(tuples), capture_output=False)
+    return subprocess.run(
+        get_tuples_args(tuples), capture_output=False, check=True
+    )
 
 
 def run_line(*tuples, charset: str = txt.CHARSET) -> str:
@@ -23,6 +25,8 @@ def run_line(*tuples, charset: str = txt.CHARSET) -> str:
 
 
 def run_lines(*tuples, charset: str = txt.CHARSET) -> list[str]:
-    process = subprocess.run(get_tuples_args(tuples), capture_output=True)
+    process = subprocess.run(
+        get_tuples_args(tuples), capture_output=True, check=True
+    )
     string = process.stdout.decode(charset)
     return string.rstrip().splitlines()
diff --git a/rwx/txt/__init__.py b/rwx/txt/__init__.py
index edb0624..369202c 100644
--- a/rwx/txt/__init__.py
+++ b/rwx/txt/__init__.py
@@ -1 +1 @@
-CHARSET = 'UTF-8'
+CHARSET = "UTF-8"