diff --git a/.gitignore b/.gitignore
index 0800ae8..4909e08 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,5 @@
 __pycache__
 /tmp
+/.venv
 /.vscode
 /dist
diff --git a/pyproject.toml b/pyproject.toml
index ccd0aa1..66a3933 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -32,4 +32,8 @@ requires-python = ">= 3.10"
 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 a721b9a..a1c5ee6 100644
--- a/rwx/__init__.py
+++ b/rwx/__init__.py
@@ -1,2 +1,3 @@
 """Read Write eXecute."""
+
 __version__ = "0.0.1"
diff --git a/rwx/__main__.py b/rwx/__main__.py
index 519fb8e..f6276e4 100755
--- a/rwx/__main__.py
+++ b/rwx/__main__.py
@@ -1,6 +1,11 @@
 #! /usr/bin/env python3
+
+"""Entry point."""
+
 from pathlib import Path
+
 import fs
+
 if __name__ == "__main__":
     file_path = Path(__file__).resolve()
     root_path = file_path.parent
diff --git a/rwx/cmd/squashfs/__init__.py b/rwx/cmd/squashfs/__init__.py
index 343461e..322186c 100644
--- a/rwx/cmd/squashfs/__init__.py
+++ b/rwx/cmd/squashfs/__init__.py
@@ -6,10 +6,14 @@ 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/grub/__init__.py b/rwx/grub/__init__.py
index 57e313c..cd016ab 100644
--- a/rwx/grub/__init__.py
+++ b/rwx/grub/__init__.py
@@ -17,8 +17,13 @@ MODULES = {
 }
 
 
-def make_image(image_format: str, image_path: str, modules: list[str],
-               memdisk_path: str, pubkey_path: str | None = 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),
@@ -29,6 +34,6 @@ def make_image(image_format: str, image_path: str, modules: list[str],
     if 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 3502ab5..50048e5 100644
--- a/rwx/log/__init__.py
+++ b/rwx/log/__init__.py
@@ -16,13 +16,17 @@ def get_file_logger(name: str) -> logging.Logger:
     logger.setLevel(logging.INFO)
     #
     return logger
-def get_stream_logger() -> logging.Logger:
+
+
+def get_stream_logger(level: int) -> logging.Logger:
     out_handler = logging.StreamHandler(stream=sys.stdout)
-    out_handler.setLevel(logging.INFO)
+    out_handler.setLevel(level)
     #
     logger = logging.getLogger()
     logger.addHandler(out_handler)
-    logger.setLevel(logging.INFO)
+    logger.setLevel(level)
     #
     return logger
-stream = get_stream_logger()
+
+
+stream = get_stream_logger(logging.INFO)
diff --git a/rwx/prj/sphinx.py b/rwx/prj/sphinx.py
index ccb8d0f..b09d8ee 100644
--- a/rwx/prj/sphinx.py
+++ b/rwx/prj/sphinx.py
@@ -15,12 +15,18 @@ class SphinxProject(Project):
         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),
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()