diff --git a/.taskcluster.yml b/.taskcluster.yml
index a54ac62..fc068b0 100644
--- a/.taskcluster.yml
+++ b/.taskcluster.yml
@@ -20,10 +20,6 @@ tasks:
         - tox; tox -e codecov
       jobs:
         include:
-          - name: tests python 3.8
-            version: "3.8"
-            env:
-              TOXENV: py38,lint
           - name: tests python 3.9
             version: "3.9"
             env:
@@ -51,7 +47,7 @@ tasks:
             env:
               TOXENV: py312,lint
           - name: PyPI upload
-            version: "3.8"
+            version: "3.9"
             env:
               TOXENV: pypi
             script:
diff --git a/pyproject.toml b/pyproject.toml
index ad7e7fa..967a216 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -53,7 +53,7 @@ log_level = "DEBUG"
 
 [tool.ruff]
 fix = true
-target-version = "py38"
+target-version = "py39"
 
 [tool.ruff.lint]
 select = [
@@ -82,7 +82,6 @@ select = [
 ]
 ignore = [
     "PERF203",
-    "SIM117",
 ]
 
 [tool.setuptools_scm]
diff --git a/setup.cfg b/setup.cfg
index 9cef2e2..8853b30 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -25,7 +25,7 @@ package_dir =
     = src
 packages =
     ffpuppet
-python_requires = >=3.8
+python_requires = >=3.9
 zip_safe = False
 
 [options.entry_points]
diff --git a/src/ffpuppet/checks.py b/src/ffpuppet/checks.py
index 34d39aa..5daf567 100644
--- a/src/ffpuppet/checks.py
+++ b/src/ffpuppet/checks.py
@@ -7,10 +7,14 @@
 from abc import ABC, abstractmethod
 from os import SEEK_SET, stat
 from platform import system
-from typing import IO, Callable, Iterable, Pattern
+from typing import IO, TYPE_CHECKING, Callable
 
 from psutil import AccessDenied, NoSuchProcess, Process
 
+if TYPE_CHECKING:
+    from collections.abc import Iterable
+    from re import Pattern
+
 __author__ = "Tyson Smith"
 __credits__ = ["Tyson Smith"]
 
diff --git a/src/ffpuppet/core.py b/src/ffpuppet/core.py
index e96e59d..464442d 100644
--- a/src/ffpuppet/core.py
+++ b/src/ffpuppet/core.py
@@ -12,13 +12,12 @@
 from os.path import isfile, realpath
 from pathlib import Path
 from platform import system
-from re import IGNORECASE
+from re import IGNORECASE, Pattern
 from re import compile as re_compile
 from re import match as re_match
 from shutil import copy, copyfileobj
 from subprocess import Popen, check_output
 from sys import executable
-from typing import Generator, Pattern
 from urllib.request import pathname2url
 
 with suppress(ImportError):
@@ -30,6 +29,8 @@
 with suppress(ImportError):
     from xvfbwrapper import Xvfb
 
+from typing import TYPE_CHECKING
+
 from .bootstrapper import Bootstrapper
 from .checks import CheckLogContents, CheckLogSize, CheckMemoryUsage
 from .exceptions import BrowserExecutionError, InvalidPrefs, LaunchError
@@ -39,6 +40,9 @@
 from .profile import Profile
 from .puppet_logger import PuppetLogger
 
+if TYPE_CHECKING:
+    from collections.abc import Generator
+
 if system() == "Windows":
     # config_job_object is only available on Windows
     from .job_object import config_job_object, resume_suspended_process
diff --git a/src/ffpuppet/helpers.py b/src/ffpuppet/helpers.py
index 0c057b7..4405480 100644
--- a/src/ffpuppet/helpers.py
+++ b/src/ffpuppet/helpers.py
@@ -12,12 +12,15 @@
 from stat import S_IWUSR
 from subprocess import STDOUT, CalledProcessError, check_output
 from time import sleep, time
-from typing import Any, Callable, Generator, Iterable
+from typing import TYPE_CHECKING, Any, Callable
 
 from psutil import Process, process_iter
 
 from .sanitizer_util import SanitizerOptions
 
+if TYPE_CHECKING:
+    from collections.abc import Generator, Iterable
+
 if system() == "Windows":
     from .lsof import pids_by_file
 
diff --git a/src/ffpuppet/minidump_parser.py b/src/ffpuppet/minidump_parser.py
index c29a7f1..05f9296 100644
--- a/src/ffpuppet/minidump_parser.py
+++ b/src/ffpuppet/minidump_parser.py
@@ -168,32 +168,34 @@ def create_log(self, src: Path, filename: str, timeout: int = 300) -> Path:
         cmd = self._cmd(src)
         dst = self._storage / filename
         # using nested with statements for python 3.8 support
-        with TemporaryFile(dir=self._storage, prefix="mdsw_out_") as out_fp:
-            with TemporaryFile(dir=self._storage, prefix="mdsw_err_") as err_fp:
-                LOG.debug("running %r", " ".join(cmd))
-                try:
-                    run(cmd, check=True, stderr=err_fp, stdout=out_fp, timeout=timeout)
-                    out_fp.seek(0)
-                    # load json, format data and write log
-                    with dst.open("wb") as log_fp:
-                        self._fmt_output(load(out_fp), log_fp)
-                except (CalledProcessError, JSONDecodeError, TimeoutExpired) as exc:
-                    if isinstance(exc, CalledProcessError):
-                        msg = f"minidump-stackwalk failed ({exc.returncode})"
-                    elif isinstance(exc, JSONDecodeError):
-                        msg = "json decode error"
-                    else:
-                        msg = "minidump-stackwalk timeout"
-                    LOG.warning("Failed to parse minidump: %s", msg)
-                    err_fp.seek(0)
-                    out_fp.seek(0)
-                    # write log
-                    with dst.open("wb") as log_fp:
-                        log_fp.write(f"Failed to parse minidump: {msg}".encode())
-                        log_fp.write(b"\n\nminidump-stackwalk stderr:\n")
-                        log_fp.write(err_fp.read())
-                        log_fp.write(b"\n\nminidump-stackwalk stdout:\n")
-                        log_fp.write(out_fp.read())
+        with (
+            TemporaryFile(dir=self._storage, prefix="mdsw_out_") as out_fp,
+            TemporaryFile(dir=self._storage, prefix="mdsw_err_") as err_fp,
+        ):
+            LOG.debug("running %r", " ".join(cmd))
+            try:
+                run(cmd, check=True, stderr=err_fp, stdout=out_fp, timeout=timeout)
+                out_fp.seek(0)
+                # load json, format data and write log
+                with dst.open("wb") as log_fp:
+                    self._fmt_output(load(out_fp), log_fp)
+            except (CalledProcessError, JSONDecodeError, TimeoutExpired) as exc:
+                if isinstance(exc, CalledProcessError):
+                    msg = f"minidump-stackwalk failed ({exc.returncode})"
+                elif isinstance(exc, JSONDecodeError):
+                    msg = "json decode error"
+                else:
+                    msg = "minidump-stackwalk timeout"
+                LOG.warning("Failed to parse minidump: %s", msg)
+                err_fp.seek(0)
+                out_fp.seek(0)
+                # write log
+                with dst.open("wb") as log_fp:
+                    log_fp.write(f"Failed to parse minidump: {msg}".encode())
+                    log_fp.write(b"\n\nminidump-stackwalk stderr:\n")
+                    log_fp.write(err_fp.read())
+                    log_fp.write(b"\n\nminidump-stackwalk stdout:\n")
+                    log_fp.write(out_fp.read())
         return dst
 
     @staticmethod
diff --git a/src/ffpuppet/process_tree.py b/src/ffpuppet/process_tree.py
index a2048f1..7dcae5e 100644
--- a/src/ffpuppet/process_tree.py
+++ b/src/ffpuppet/process_tree.py
@@ -10,7 +10,7 @@
 from pathlib import Path
 from platform import system
 from time import perf_counter, sleep
-from typing import TYPE_CHECKING, Callable, Generator, Iterable, List, Tuple, cast
+from typing import TYPE_CHECKING, Callable, cast
 
 try:
     from signal import SIGUSR1, Signals
@@ -24,6 +24,7 @@
 from .exceptions import TerminateError
 
 if TYPE_CHECKING:
+    from collections.abc import Generator, Iterable
     from subprocess import Popen
 
 LOG = getLogger(__name__)
@@ -64,9 +65,8 @@ def _safe_wait_procs(
     while True:
         remaining = None if deadline is None else max(deadline - perf_counter(), 0)
         with suppress(AccessDenied):
-            # Python 3.8 is not compatible with __future__.annotations in cast()
             return cast(
-                Tuple[List[Process], List[Process]],
+                tuple[list[Process], list[Process]],
                 wait_procs(procs, timeout=remaining, callback=callback),
             )
         if deadline is not None and deadline <= perf_counter():
diff --git a/src/ffpuppet/puppet_logger.py b/src/ffpuppet/puppet_logger.py
index c1c3a5f..4ea6c3d 100644
--- a/src/ffpuppet/puppet_logger.py
+++ b/src/ffpuppet/puppet_logger.py
@@ -13,10 +13,13 @@
 from shutil import copy2, copyfileobj, copytree, rmtree
 from subprocess import STDOUT, CalledProcessError, check_output
 from tempfile import NamedTemporaryFile, mkdtemp
-from typing import IO, Iterator, KeysView
+from typing import IO, TYPE_CHECKING
 
 from .helpers import onerror, warn_open
 
+if TYPE_CHECKING:
+    from collections.abc import Iterator, KeysView
+
 LOG = getLogger(__name__)
 
 __author__ = "Tyson Smith"
@@ -278,11 +281,13 @@ def save_logs(
                 # check logs for rr related issues
                 # OSError: in case the file does not exist
                 # ValueError: cannot mmap an empty file on Windows
-                with suppress(OSError, ValueError):
-                    with (dest / "log_stderr.txt").open("rb") as lfp:
-                        with mmap(lfp.fileno(), 0, access=ACCESS_READ) as lmm:
-                            if lmm.find(b"=== Start rr backtrace:") != -1:
-                                LOG.warning("rr traceback detected in stderr log")
+                with (
+                    suppress(OSError, ValueError),
+                    (dest / "log_stderr.txt").open("rb") as lfp,
+                    mmap(lfp.fileno(), 0, access=ACCESS_READ) as lmm,
+                ):
+                    if lmm.find(b"=== Start rr backtrace:") != -1:
+                        LOG.warning("rr traceback detected in stderr log")
                 if rr_pack and not self._rr_packed:
                     LOG.debug("packing rr trace")
                     try:
diff --git a/src/ffpuppet/sanitizer_util.py b/src/ffpuppet/sanitizer_util.py
index a1dd719..a57e9b1 100644
--- a/src/ffpuppet/sanitizer_util.py
+++ b/src/ffpuppet/sanitizer_util.py
@@ -7,7 +7,10 @@
 from logging import getLogger
 from os.path import exists
 from re import compile as re_compile
-from typing import Iterator
+from typing import TYPE_CHECKING
+
+if TYPE_CHECKING:
+    from collections.abc import Iterator
 
 LOG = getLogger(__name__)
 
diff --git a/src/ffpuppet/test_bootstrapper.py b/src/ffpuppet/test_bootstrapper.py
index 951aac8..36042c3 100644
--- a/src/ffpuppet/test_bootstrapper.py
+++ b/src/ffpuppet/test_bootstrapper.py
@@ -111,9 +111,11 @@ def test_bootstrapper_05(mocker):
     fake_conn.recv.return_value = "foo"
     fake_sock.accept.return_value = (fake_conn, None)
     mocker.patch("ffpuppet.bootstrapper.select", return_value=([fake_sock], None, None))
-    with Bootstrapper(fake_sock) as bts:
-        with raises(BrowserTerminatedError, match="Failure during browser startup"):
-            bts.wait(lambda: False)
+    with (
+        Bootstrapper(fake_sock) as bts,
+        raises(BrowserTerminatedError, match="Failure during browser startup"),
+    ):
+        bts.wait(lambda: False)
     assert fake_conn.close.call_count == 1
 
 
@@ -197,9 +199,8 @@ def test_bootstrapper_08(mocker, bind, attempts, raised):
     fake_sock.bind.side_effect = bind
     mocker.patch("ffpuppet.bootstrapper.select", return_value=([fake_sock], None, None))
     mocker.patch("ffpuppet.bootstrapper.socket", return_value=fake_sock)
-    with raises(raised):
-        with Bootstrapper.create(attempts=attempts):
-            pass
+    with raises(raised), Bootstrapper.create(attempts=attempts):
+        pass
     assert fake_sock.bind.call_count == attempts
     assert fake_sock.close.call_count == attempts
 
diff --git a/src/ffpuppet/test_ffpuppet.py b/src/ffpuppet/test_ffpuppet.py
index 7d959d3..4f705bf 100644
--- a/src/ffpuppet/test_ffpuppet.py
+++ b/src/ffpuppet/test_ffpuppet.py
@@ -79,9 +79,8 @@ def _srv_thread(httpd):
 @mark.skipif(system() == "Windows", reason="Unsupported on Windows")
 def test_ffpuppet_00(tmp_path):
     """test that invalid executables raise the right exception"""
-    with FFPuppet() as ffp:
-        with raises(OSError, match="is not an executable"):
-            ffp.launch(tmp_path)
+    with FFPuppet() as ffp, raises(OSError, match="is not an executable"):
+        ffp.launch(tmp_path)
 
 
 def test_ffpuppet_01():
@@ -415,21 +414,22 @@ def test_ffpuppet_15(mocker, tmp_path, debugger, dbg_bin, version):
 
 def test_ffpuppet_16(tmp_path):
     """test calling save_logs() before close()"""
-    with FFPuppet() as ffp:
-        with HTTPTestServer() as srv:
-            ffp.launch(TESTFF_BIN, location=srv.get_addr())
-            with raises(AssertionError):
-                ffp.save_logs(tmp_path / "logs")
+    with FFPuppet() as ffp, HTTPTestServer() as srv:
+        ffp.launch(TESTFF_BIN, location=srv.get_addr())
+        with raises(AssertionError):
+            ffp.save_logs(tmp_path / "logs")
 
 
 def test_ffpuppet_17(tmp_path):
     """test detecting invalid prefs file"""
     prefs = tmp_path / "prefs.js"
     prefs.write_bytes(b"//fftest_invalid_js\n")
-    with FFPuppet() as ffp:
-        with HTTPTestServer() as srv:
-            with raises(LaunchError, match="'.+?' is invalid"):
-                ffp.launch(TESTFF_BIN, location=srv.get_addr(), prefs_js=prefs)
+    with (
+        FFPuppet() as ffp,
+        HTTPTestServer() as srv,
+        raises(LaunchError, match="'.+?' is invalid"),
+    ):
+        ffp.launch(TESTFF_BIN, location=srv.get_addr(), prefs_js=prefs)
 
 
 def test_ffpuppet_18():
diff --git a/src/ffpuppet/test_profile.py b/src/ffpuppet/test_profile.py
index 8a1cc8c..bc7a619 100644
--- a/src/ffpuppet/test_profile.py
+++ b/src/ffpuppet/test_profile.py
@@ -204,9 +204,11 @@ def test_profile_06(mocker, tmp_path):
     mocker.patch("ffpuppet.profile.rmtree", autospec=True, side_effect=OSError("test"))
     with Profile(working_path=str(tmp_path)) as profile:
         profile.remove(ignore_errors=True)
-    with Profile(working_path=str(tmp_path)) as profile:
-        with raises(OSError, match="test"):
-            profile.remove(ignore_errors=False)
+    with (
+        Profile(working_path=str(tmp_path)) as profile,
+        raises(OSError, match="test"),
+    ):
+        profile.remove(ignore_errors=False)
 
 
 def test_profile_07(mocker, tmp_path):
diff --git a/src/ffpuppet/test_puppet_logger.py b/src/ffpuppet/test_puppet_logger.py
index 5360b14..b207b35 100644
--- a/src/ffpuppet/test_puppet_logger.py
+++ b/src/ffpuppet/test_puppet_logger.py
@@ -221,11 +221,13 @@ def test_puppet_logger_07(mocker, tmp_path):
 
 def test_puppet_logger_08(tmp_path):
     """test PuppetLogger.add_log() with file not on disk"""
-    with PuppetLogger(base_path=str(tmp_path)) as plog:
-        with SpooledTemporaryFile(max_size=2048) as log_fp:
-            plog.add_log("test", logfp=log_fp)
-            with raises(OSError, match="log file None does not exist"):
-                plog.get_fp("test")
+    with (
+        PuppetLogger(base_path=str(tmp_path)) as plog,
+        SpooledTemporaryFile(max_size=2048) as log_fp,
+    ):
+        plog.add_log("test", logfp=log_fp)
+        with raises(OSError, match="log file None does not exist"):
+            plog.get_fp("test")
 
 
 def test_puppet_logger_09(mocker, tmp_path):
diff --git a/tox.ini b/tox.ini
index fa31408..2db076b 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,5 +1,5 @@
 [tox]
-envlist = py{38,39,310,311,312},lint
+envlist = py{39,310,311,312},lint
 skip_missing_interpreters = true
 tox_pip_extensions_ext_venv_update = true