diff --git a/.github/workflows/style.yaml b/.github/workflows/style.yaml
index d3f6384f8..59fd1c95a 100644
--- a/.github/workflows/style.yaml
+++ b/.github/workflows/style.yaml
@@ -37,4 +37,6 @@ jobs:
       - name: install tox
         run: pip install tox
       - name: run tests
-        run: tox --verbose -e pep8
+        run: |
+          tox --verbose -e pep8
+          tox --verbose -e lint
diff --git a/.gitignore b/.gitignore
index a90ba86f5..fc2a632f8 100644
--- a/.gitignore
+++ b/.gitignore
@@ -10,6 +10,7 @@ dist/
 doc/changelog.rst
 venv*
 website-build/
+.ruff_cache/
 
 # auto-generated by hatch
 eventlet/_version.py
diff --git a/eventlet/backdoor.py b/eventlet/backdoor.py
index c72ac1e87..3f3887fce 100644
--- a/eventlet/backdoor.py
+++ b/eventlet/backdoor.py
@@ -2,8 +2,6 @@
 import errno
 import socket
 import sys
-import errno
-import traceback
 
 import eventlet
 from eventlet import hubs
diff --git a/eventlet/greenio/py2.py b/eventlet/greenio/py2.py
deleted file mode 100644
index a6fdca774..000000000
--- a/eventlet/greenio/py2.py
+++ /dev/null
@@ -1,229 +0,0 @@
-import errno
-import os
-
-from eventlet.greenio.base import (
-    _operation_on_closed_file,
-    greenpipe_doc,
-    set_nonblocking,
-    socket,
-    SOCKET_BLOCKING,
-)
-from eventlet.hubs import trampoline, notify_close, notify_opened, IOClosed
-from eventlet.support import get_errno
-
-__all__ = ['_fileobject', 'GreenPipe']
-
-_fileobject = socket._fileobject
-
-
-class GreenPipe(_fileobject):
-
-    __doc__ = greenpipe_doc
-
-    def __init__(self, f, mode='r', bufsize=-1):
-        if not isinstance(f, (str,) + (int, file)):
-            raise TypeError('f(ile) should be int, str, unicode or file, not %r' % f)
-
-        if isinstance(f, str):
-            f = open(f, mode, 0)
-
-        if isinstance(f, int):
-            fileno = f
-            self._name = "<fd:%d>" % fileno
-        else:
-            fileno = os.dup(f.fileno())
-            self._name = f.name
-            if f.mode != mode:
-                raise ValueError('file.mode %r does not match mode parameter %r' % (f.mode, mode))
-            self._name = f.name
-            f.close()
-
-        super().__init__(_SocketDuckForFd(fileno), mode, bufsize)
-        set_nonblocking(self)
-        self.softspace = 0
-
-    @property
-    def name(self):
-        return self._name
-
-    def __repr__(self):
-        return "<%s %s %r, mode %r at 0x%x>" % (
-            self.closed and 'closed' or 'open',
-            self.__class__.__name__,
-            self.name,
-            self.mode,
-            (id(self) < 0) and (sys.maxint + id(self)) or id(self))
-
-    def close(self):
-        super().close()
-        for method in [
-                'fileno', 'flush', 'isatty', 'next', 'read', 'readinto',
-                'readline', 'readlines', 'seek', 'tell', 'truncate',
-                'write', 'xreadlines', '__iter__', '__next__', 'writelines']:
-            setattr(self, method, _operation_on_closed_file)
-
-    def __enter__(self):
-        return self
-
-    def __exit__(self, *args):
-        self.close()
-
-    def _get_readahead_len(self):
-        return len(self._rbuf.getvalue())
-
-    def _clear_readahead_buf(self):
-        len = self._get_readahead_len()
-        if len > 0:
-            self.read(len)
-
-    def tell(self):
-        self.flush()
-        try:
-            return os.lseek(self.fileno(), 0, 1) - self._get_readahead_len()
-        except OSError as e:
-            raise OSError(*e.args)
-
-    def seek(self, offset, whence=0):
-        self.flush()
-        if whence == 1 and offset == 0:  # tell synonym
-            return self.tell()
-        if whence == 1:  # adjust offset by what is read ahead
-            offset -= self._get_readahead_len()
-        try:
-            rv = os.lseek(self.fileno(), offset, whence)
-        except OSError as e:
-            raise OSError(*e.args)
-        else:
-            self._clear_readahead_buf()
-            return rv
-
-    if getattr(file, "truncate", None):  # not all OSes implement truncate
-        def truncate(self, size=-1):
-            self.flush()
-            if size == -1:
-                size = self.tell()
-            try:
-                rv = os.ftruncate(self.fileno(), size)
-            except OSError as e:
-                raise OSError(*e.args)
-            else:
-                self.seek(size)  # move position&clear buffer
-                return rv
-
-    def isatty(self):
-        try:
-            return os.isatty(self.fileno())
-        except OSError as e:
-            raise OSError(*e.args)
-
-
-class _SocketDuckForFd:
-    """Class implementing all socket method used by _fileobject
-    in cooperative manner using low level os I/O calls.
-    """
-    _refcount = 0
-
-    def __init__(self, fileno):
-        self._fileno = fileno
-        notify_opened(fileno)
-        self._closed = False
-
-    def _trampoline(self, fd, read=False, write=False, timeout=None, timeout_exc=None):
-        if self._closed:
-            # Don't trampoline if we're already closed.
-            raise IOClosed()
-        try:
-            return trampoline(fd, read=read, write=write, timeout=timeout,
-                              timeout_exc=timeout_exc,
-                              mark_as_closed=self._mark_as_closed)
-        except IOClosed:
-            # Our fileno has been obsoleted. Defang ourselves to
-            # prevent spurious closes.
-            self._mark_as_closed()
-            raise
-
-    def _mark_as_closed(self):
-        current = self._closed
-        self._closed = True
-        return current
-
-    @property
-    def _sock(self):
-        return self
-
-    def fileno(self):
-        return self._fileno
-
-    def recv(self, buflen):
-        while True:
-            try:
-                data = os.read(self._fileno, buflen)
-                return data
-            except OSError as e:
-                if get_errno(e) not in SOCKET_BLOCKING:
-                    raise OSError(*e.args)
-            self._trampoline(self, read=True)
-
-    def recv_into(self, buf, nbytes=0, flags=0):
-        if nbytes == 0:
-            nbytes = len(buf)
-        data = self.recv(nbytes)
-        buf[:nbytes] = data
-        return len(data)
-
-    def send(self, data):
-        while True:
-            try:
-                return os.write(self._fileno, data)
-            except OSError as e:
-                if get_errno(e) not in SOCKET_BLOCKING:
-                    raise OSError(*e.args)
-                else:
-                    trampoline(self, write=True)
-
-    def sendall(self, data):
-        len_data = len(data)
-        os_write = os.write
-        fileno = self._fileno
-        try:
-            total_sent = os_write(fileno, data)
-        except OSError as e:
-            if get_errno(e) != errno.EAGAIN:
-                raise OSError(*e.args)
-            total_sent = 0
-        while total_sent < len_data:
-            self._trampoline(self, write=True)
-            try:
-                total_sent += os_write(fileno, data[total_sent:])
-            except OSError as e:
-                if get_errno(e) != errno. EAGAIN:
-                    raise OSError(*e.args)
-
-    def __del__(self):
-        self._close()
-
-    def _close(self):
-        was_closed = self._mark_as_closed()
-        if was_closed:
-            return
-        if notify_close:
-            # If closing from __del__, notify_close may have
-            # already been cleaned up and set to None
-            notify_close(self._fileno)
-        try:
-            os.close(self._fileno)
-        except:
-            # os.close may fail if __init__ didn't complete
-            # (i.e file dscriptor passed to popen was invalid
-            pass
-
-    def __repr__(self):
-        return "%s:%d" % (self.__class__.__name__, self._fileno)
-
-    def _reuse(self):
-        self._refcount += 1
-
-    def _drop(self):
-        self._refcount -= 1
-        if self._refcount == 0:
-            self._close()
diff --git a/eventlet/patcher.py b/eventlet/patcher.py
index 366de161d..660866131 100644
--- a/eventlet/patcher.py
+++ b/eventlet/patcher.py
@@ -265,7 +265,7 @@ def monkey_patch(**on):
             raise TypeError("monkey_patch() got an unexpected "
                             "keyword argument %r" % k)
     if default_on is None:
-        default_on = not (True in on.values())
+        default_on = True not in on.values()
     for modname in accepted_args:
         if modname == 'MySQLdb':
             # MySQLdb is only on when explicitly patched for the moment
diff --git a/eventlet/zipkin/api.py b/eventlet/zipkin/api.py
index 8a33a4b2b..8edde5c61 100644
--- a/eventlet/zipkin/api.py
+++ b/eventlet/zipkin/api.py
@@ -155,10 +155,11 @@ def build_span(name, trace_id, span_id, parent_id,
 
     @staticmethod
     def build_annotation(value, endpoint=None):
-        if isinstance(value, unicode):
+        if isinstance(value, str):
             value = value.encode('utf-8')
+        assert isinstance(value, bytes)
         return ttypes.Annotation(time.time() * 1000 * 1000,
-                                 str(value), endpoint)
+                                 value, endpoint)
 
     @staticmethod
     def build_binary_annotation(key, value, endpoint=None):
diff --git a/pyproject.toml b/pyproject.toml
index 6f152287b..29beb5c01 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -61,3 +61,25 @@ version.source = "vcs"
 
 [tool.hatch.build.hooks.vcs]
 version-file = "eventlet/_version.py"
+
+[tool.ruff]
+# Might eventually want to add evenetlet/green/, but it's a pain...
+exclude = ["eventlet/green/", "eventlet/zipkin/_thrift", "tests/mock.py", "doc/"]
+line-length = 123
+
+[tool.ruff.lint]
+# Too many to fix as first pass, but should perhaps go back and fix these:
+ignore = [
+    # Ambiguous variable name
+    "E741",
+    # Local variable assigned but unused
+    "F841",
+    # Imported but unused
+    "F401",
+    # Bare except:
+    "E722",
+    # Module-level import not at top of file
+    "E402",
+    # Using a lambda expression with a name instead of just def
+    "E731",
+]
diff --git a/tests/greenio_test.py b/tests/greenio_test.py
index 36d0030a0..ce87cf54e 100644
--- a/tests/greenio_test.py
+++ b/tests/greenio_test.py
@@ -84,7 +84,7 @@ def test_connect_timeout(self):
             expect_socket_timeout(gs.connect, ('192.0.2.1', 80))
         except OSError as e:
             # unreachable is also a valid outcome
-            if not get_errno(e) in (errno.EHOSTUNREACH, errno.ENETUNREACH):
+            if get_errno(e) not in (errno.EHOSTUNREACH, errno.ENETUNREACH):
                 raise
 
     def test_accept_timeout(self):
diff --git a/tests/greenpool_test.py b/tests/greenpool_test.py
index 6ff9aa0c9..7d0207411 100644
--- a/tests/greenpool_test.py
+++ b/tests/greenpool_test.py
@@ -7,11 +7,6 @@
 import tests
 
 
-def passthru(a):
-    eventlet.sleep(0.01)
-    return a
-
-
 def passthru2(a, b):
     eventlet.sleep(0.01)
     return a, b
diff --git a/tests/isolated/patcher_builtin.py b/tests/isolated/patcher_builtin.py
index 56b2dbe21..c0c002186 100644
--- a/tests/isolated/patcher_builtin.py
+++ b/tests/isolated/patcher_builtin.py
@@ -1,14 +1,10 @@
 if __name__ == '__main__':
     from tests.mock import patch
 
-    import sys
     import eventlet
     from eventlet import hubs
     with patch.object(hubs, 'notify_opened') as mock_func:
         eventlet.monkey_patch(builtins=True)
         with open(__file__) as f:
             mock_func.assert_called_with(f.fileno())
-        if sys.version_info.major == 2:
-            with file(__file__, 'r') as f:
-                mock_func.assert_called_with(f.fileno())
     print('pass')
diff --git a/tests/parse_results.py b/tests/parse_results.py
index d865d10cf..ba6a960d4 100644
--- a/tests/parse_results.py
+++ b/tests/parse_results.py
@@ -111,4 +111,4 @@ def main(db):
         sys.argv.append(latest_db)
     for db in sys.argv[1:]:
         main(db)
-    execfile('generate_report.py')
+    exec(open('generate_report.py').read())
diff --git a/tests/ssl_test.py b/tests/ssl_test.py
index 1ce338ca7..56bf7b27b 100644
--- a/tests/ssl_test.py
+++ b/tests/ssl_test.py
@@ -1,6 +1,4 @@
-import contextlib
 import random
-import socket
 import sys
 import warnings
 
diff --git a/tox.ini b/tox.ini
index 06f0b5b82..debe7dcc5 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,10 +1,5 @@
 # The flake8 and pep8 sections just contain configuration for corresponding tools.
 # Checkers are not run implicitly.
-[flake8]
-exclude = *.egg*,.env,.git,.hg,.tox,_*,build*,dist*,venv*,mock.py,eventlet/green/http/*
-ignore = E261,E402,E731,W503
-max-line-length = 123
-
 [pycodestyle]
 count = 1
 exclude = *.egg*,.env,.git,.hg,.tox,_*,build*,dist*,venv*,mock.py,eventlet/green/http/*
@@ -49,6 +44,15 @@ usedevelop = False
 commands =
     pycodestyle benchmarks/ eventlet/ tests/
 
+[testenv:lint]
+basepython = python3
+setenv =
+    {[testenv]setenv}
+deps =
+    ruff==0.1.13
+commands =
+    ruff eventlet/ tests/
+
 [testenv]
 passenv =
     CI