diff --git a/zapp/compiler/__main__.py b/zapp/compiler/__main__.py
index 1328bd7..eaeea24 100644
--- a/zapp/compiler/__main__.py
+++ b/zapp/compiler/__main__.py
@@ -6,19 +6,18 @@ import argparse
 import io
 import json
 import os
-import ast
 import pathlib
-from itertools import chain
 import stat
 import sys
-from collections import defaultdict
 import zipfile
+from collections import defaultdict
 from email.parser import Parser
+from itertools import chain
 from shutil import move
 from tempfile import TemporaryDirectory
 
-from zapp.support.unpack import cache_wheel_path
 from zapp.support.pep425 import compress_tags, decompress_tag
+from zapp.support.unpack import cache_wheel_path
 
 parser = argparse.ArgumentParser(description="The (bootstrap) Zapp compiler")
 parser.add_argument("-o", "--out", dest="output", help="Output target file")
@@ -84,12 +83,14 @@ def load_wheel(opts, manifest, path):
 
     def _parse_email(msg):
         msg = Parser().parsestr(msg)
+
         def _get(k):
             v = msg.get_all(k)
             if len(v) == 1:
                 return v[0]
             else:
                 return v
+
         return {k: _get(k) for k in msg.keys()}
 
     # RECORD seems to just record file reference checksums for validation
@@ -104,7 +105,14 @@ def load_wheel(opts, manifest, path):
 
     prefix = os.path.dirname(path)
 
-    sources = [(dest, spec,) for dest, spec in manifest["sources"] if spec["source"].startswith(prefix)]
+    sources = [
+        (
+            dest,
+            spec,
+        )
+        for dest, spec in manifest["sources"]
+        if spec["source"].startswith(prefix)
+    ]
 
     return {
         # "record": record,
@@ -171,6 +179,7 @@ def rezip_wheels(opts, manifest):
 
         if opts.debug:
             from pprint import pprint
+
             print("---")
             pprint({"$type": "whl", **w})
 
@@ -187,7 +196,6 @@ def rezip_wheels(opts, manifest):
             else:
                 wf = zip_wheel(opts.tmpdir, w)
 
-
             # Insert a new wheel source
             manifest["wheels"][wn] = {"hashes": [], "source": wf}
 
@@ -248,15 +256,19 @@ def enable_unzipping(opts, manifest):
     """Inject unzipping behavior as needed."""
 
     if manifest["wheels"]:
-        manifest["prelude_points"].extend([
-            "zapp.support.unpack:unpack_deps",
-            "zapp.support.unpack:install_deps",
-        ])
+        manifest["prelude_points"].extend(
+            [
+                "zapp.support.unpack:unpack_deps",
+                "zapp.support.unpack:install_deps",
+            ]
+        )
 
     if not manifest["zip_safe"]:
-        manifest["prelude_points"].extend([
-            "zapp.support.unpack:unpack_zapp",
-        ])
+        manifest["prelude_points"].extend(
+            [
+                "zapp.support.unpack:unpack_zapp",
+            ]
+        )
 
     return manifest
 
diff --git a/zapp/support/pep425.py b/zapp/support/pep425.py
index 51ab577..020da9d 100644
--- a/zapp/support/pep425.py
+++ b/zapp/support/pep425.py
@@ -13,9 +13,9 @@ def decompress_tag(tag: str) -> t.Iterable[Tag]:
     """Decompress tag string into a sequence of compatible tuples."""
 
     pytags, abitags, archtags = tag.split("-", 2)
-    for x in pytags.split('.'):
-        for y in abitags.split('.'):
-            for z in archtags.split('.'):
+    for x in pytags.split("."):
+        for y in abitags.split("."):
+            for z in archtags.split("."):
                 yield Tag(x, y, z)
 
 
@@ -27,10 +27,12 @@ def compress_tags(tags: t.Iterable[Tag]) -> str:
     abitags = set(t.abi for t in tags)
     archtags = set(t.arch for t in tags)
 
-    tag = "-".join([
-        ".".join(sorted(pytags)),
-        ".".join(sorted(abitags)),
-        ".".join(sorted(archtags)),
-    ])
+    tag = "-".join(
+        [
+            ".".join(sorted(pytags)),
+            ".".join(sorted(abitags)),
+            ".".join(sorted(archtags)),
+        ]
+    )
     assert set(decompress_tag(tag)) == tags
     return tag
diff --git a/zapp/support/unpack.py b/zapp/support/unpack.py
index fd00efe..149b33b 100644
--- a/zapp/support/unpack.py
+++ b/zapp/support/unpack.py
@@ -115,7 +115,11 @@ def unpack_zapp():
                     of.write(zf.read(src))
 
         # Re-exec the current interpreter
-        args = [sys.executable, "--", os.path.join(tmpdir, "usr", "__main__.py")] + sys.argv[1:]
+        args = [
+            sys.executable,
+            "--",
+            os.path.join(tmpdir, "usr", "__main__.py"),
+        ] + sys.argv[1:]
         os.execvpe(args[0], args[1:], {"PYTHONPATH": "", "ZAPP_TMPDIR": tmpdir})
 
     else: