diff --git a/nvitop/api/collector.py b/nvitop/api/collector.py
index 5887cae..4496a4d 100644
--- a/nvitop/api/collector.py
+++ b/nvitop/api/collector.py
@@ -250,7 +250,7 @@ def collect_in_background(
         raise ValueError(f'Invalid argument interval={interval!r}')
     interval = min(interval, collector.interval)
 
-    def target():
+    def target() -> None:
         if on_start is not None:
             on_start(collector)
         try:
@@ -402,10 +402,7 @@ class ResourceMetricCollector:  # pylint: disable=too-many-instance-attributes
         if devices is None:
             devices = Device.all()
 
-        if root_pids is None:
-            root_pids = {os.getpid()}
-        else:
-            root_pids = set(root_pids)
+        root_pids = {os.getpid()} if root_pids is None else set(root_pids)
 
         self.interval = interval
 
diff --git a/nvitop/api/device.py b/nvitop/api/device.py
index 72c8f6e..1dfff37 100644
--- a/nvitop/api/device.py
+++ b/nvitop/api/device.py
@@ -2019,7 +2019,7 @@ class MigDevice(Device):  # pylint: disable=too-many-instance-attributes
 
         return snapshot
 
-    SNAPSHOT_KEYS = Device.SNAPSHOT_KEYS + ['gpu_instance_id', 'compute_instance_id']
+    SNAPSHOT_KEYS = [*Device.SNAPSHOT_KEYS, 'gpu_instance_id', 'compute_instance_id']
 
 
 class CudaDevice(Device):
@@ -2387,15 +2387,14 @@ def normalize_cuda_visible_devices(cuda_visible_devices: Optional[str] = _VALUE_
 
 # Helper functions #################################################################################
 
-_PhysicalDeviceAttrs = NamedTuple(
-    'PhysicalDeviceAttrs',
-    [
-        ('index', int),
-        ('name', str),
-        ('uuid', str),
-        ('support_mig_mode', bool),
-    ],
-)
+
+class _PhysicalDeviceAttrs(NamedTuple):
+    index: int
+    name: str
+    uuid: str
+    support_mig_mode: bool
+
+
 _PHYSICAL_DEVICE_ATTRS = None
 _GLOBAL_PHYSICAL_DEVICE = None
 _GLOBAL_PHYSICAL_DEVICE_LOCK = threading.RLock()
@@ -2551,7 +2550,7 @@ def _parse_cuda_visible_devices(  # pylint: disable=too-many-branches,too-many-s
 
 def _parse_cuda_visible_devices_to_uuids(
     cuda_visible_devices: Optional[str] = _VALUE_OMITTED,
-    verbose=True,
+    verbose: bool = True,
 ) -> List[str]:
     """Parse the given ``CUDA_VISIBLE_DEVICES`` environment variable in a separate process and return a list of device UUIDs.
 
diff --git a/nvitop/api/host.py b/nvitop/api/host.py
index 0c79f2e..778dc4f 100644
--- a/nvitop/api/host.py
+++ b/nvitop/api/host.py
@@ -40,7 +40,7 @@ __all__[__all__.index('Error')] = 'PsutilError'
 
 
 PsutilError = Error  # make alias # noqa: F405
-del Error  # noqa: F405,F821 # pylint: disable=undefined-variable
+del Error  # noqa: F821 # pylint: disable=undefined-variable
 
 
 cpu_percent = _ttl_cache(ttl=0.25)(_psutil.cpu_percent)
diff --git a/nvitop/api/libcudart.py b/nvitop/api/libcudart.py
index 65e6bbc..2f89c84 100644
--- a/nvitop/api/libcudart.py
+++ b/nvitop/api/libcudart.py
@@ -483,6 +483,12 @@ def __LoadCudaLibrary() -> None:  # pylint: disable=too-many-branches
                                 _glob.iglob(_os.path.join(candidate_dir, f'cudart{bits}*.dll'))
                             )
 
+                    # Normalize paths and remove duplicates
+                    candidate_paths = list(
+                        dict.fromkeys(
+                            _os.path.normpath(_os.path.normcase(p)) for p in candidate_paths
+                        )
+                    )
                     for lib_filename in candidate_paths:
                         try:
                             __cudaLib = _ctypes.CDLL(lib_filename)
diff --git a/nvitop/api/libnvml.py b/nvitop/api/libnvml.py
index 9d9ac80..f76952d 100644
--- a/nvitop/api/libnvml.py
+++ b/nvitop/api/libnvml.py
@@ -391,10 +391,7 @@ def nvmlQuery(
         retval = func(*args, **kwargs)
     except NVMLError_FunctionNotFound as e2:
         if not ignore_function_not_found:
-            if func.__name__ == '<lambda>':
-                identifier = _inspect.getsource(func)
-            else:
-                identifier = repr(func)
+            identifier = _inspect.getsource(func) if func.__name__ == '<lambda>' else repr(func)
             with __lock:
                 if (
                     identifier not in UNKNOWN_FUNCTIONS
diff --git a/nvitop/api/process.py b/nvitop/api/process.py
index 1805b39..5d2a9cc 100644
--- a/nvitop/api/process.py
+++ b/nvitop/api/process.py
@@ -100,7 +100,9 @@ _RAISE = object()
 _USE_FALLBACK_WHEN_RAISE = threading.local()  # see also `GpuProcess.failsafe`
 
 
-def auto_garbage_clean(fallback=_RAISE):
+def auto_garbage_clean(
+    fallback: Any = _RAISE,
+) -> Callable[[Callable[..., Any]], Callable[..., Any]]:
     """Remove the object references in the instance cache if the method call fails (the process is gone).
 
     The fallback value will be used with `:meth:`GpuProcess.failsafe`` context manager, otherwise
@@ -979,7 +981,7 @@ class GpuProcess:  # pylint: disable=too-many-instance-attributes,too-many-publi
 
     @classmethod
     def take_snapshots(  # batched version of `as_snapshot`
-        cls, gpu_processes: Iterable['GpuProcess'], *, failsafe=False
+        cls, gpu_processes: Iterable['GpuProcess'], *, failsafe: bool = False
     ) -> List[Snapshot]:
         """Take snapshots for a list of :class:`GpuProcess` instances.
 
diff --git a/nvitop/callbacks/tensorboard.py b/nvitop/callbacks/tensorboard.py
index 9e90d28..04c7b91 100644
--- a/nvitop/callbacks/tensorboard.py
+++ b/nvitop/callbacks/tensorboard.py
@@ -17,8 +17,28 @@
 
 # pylint: disable=missing-module-docstring
 
+from typing import TYPE_CHECKING, Dict, Optional, Union
 
-def add_scalar_dict(writer, main_tag, tag_scalar_dict, global_step=None, walltime=None):
+
+if TYPE_CHECKING:
+    import numpy as np
+
+    try:
+        from tensorboard.summary import Writer as SummaryWriter
+    except ImportError:
+        try:
+            from tensorboardX import SummaryWriter
+        except ImportError:
+            pass
+
+
+def add_scalar_dict(
+    writer: 'SummaryWriter',
+    main_tag: str,
+    tag_scalar_dict: Dict[str, Union[int, float, 'np.floating']],
+    global_step: Optional[Union[int, 'np.integer']] = None,
+    walltime: Optional[float] = None,
+) -> None:
     """Add a batch of scalars to the writer.
 
     Batched version of ``writer.add_scalar``.
diff --git a/nvitop/cli.py b/nvitop/cli.py
index 5f301cb..8334399 100644
--- a/nvitop/cli.py
+++ b/nvitop/cli.py
@@ -19,13 +19,14 @@ NVITOP_MONITOR_MODE = set(
 )
 
 
-def parse_arguments():  # pylint: disable=too-many-branches,too-many-statements
+# pylint: disable=too-many-branches,too-many-statements
+def parse_arguments() -> argparse.Namespace:
     """Parse command-line arguments for ``nvtiop``."""
     coloring_rules = '{} < th1 %% <= {} < th2 %% <= {}'.format(
         colored('light', 'green'), colored('moderate', 'yellow'), colored('heavy', 'red')
     )
 
-    def posint(argstring):
+    def posint(argstring: str) -> int:
         num = int(argstring)
         if num <= 0:
             raise ValueError
@@ -251,7 +252,8 @@ def parse_arguments():  # pylint: disable=too-many-branches,too-many-statements
     return args
 
 
-def main():  # pylint: disable=too-many-branches,too-many-statements,too-many-locals
+# pylint: disable-next=too-many-branches,too-many-statements,too-many-locals
+def main() -> None:
     """Main function for ``nvitop`` CLI."""
     args = parse_arguments()
 
@@ -272,10 +274,7 @@ def main():  # pylint: disable=too-many-branches,too-many-statements,too-many-lo
 
     if hasattr(args, 'monitor') and args.monitor is None:
         mode = NVITOP_MONITOR_MODE.intersection({'auto', 'full', 'compact'})
-        if len(mode) != 1:
-            mode = 'auto'
-        else:
-            mode = mode.pop()
+        mode = 'auto' if len(mode) != 1 else mode.pop()
         args.monitor = mode
 
     if not setlocale_utf8():
diff --git a/nvitop/select.py b/nvitop/select.py
index 76418d8..6f082d6 100644
--- a/nvitop/select.py
+++ b/nvitop/select.py
@@ -60,7 +60,7 @@ import math
 import os
 import sys
 import warnings
-from typing import Iterable, List, Optional, Tuple, Union
+from typing import Any, Iterable, List, Optional, Tuple, Union
 
 from nvitop.api import Device, GpuProcess, colored, human2bytes, libnvml
 from nvitop.version import __version__
@@ -76,8 +76,7 @@ except ModuleNotFoundError:
 TTY = sys.stdout.isatty()
 
 
-# pylint: disable-next=too-many-branches,too-many-statements,too-many-locals
-def select_devices(
+def select_devices(  # pylint: disable=too-many-branches,too-many-statements,too-many-locals,unused-argument
     devices: Iterable[Device] = None,
     *,
     format: str = 'index',  # pylint: disable=redefined-builtin
@@ -91,7 +90,7 @@ def select_devices(
     tolerance: int = 0,  # in percentage
     free_accounts: List[str] = None,
     sort: bool = True,
-    **kwargs,  # fmt: skip # pylint: disable=unused-argument
+    **kwargs: Any,
 ) -> Union[List[int], List[Tuple[int, int]], List[str]]:
     """Select a subset of devices satisfying the specified criteria.
 
@@ -163,7 +162,7 @@ def select_devices(
     if isinstance(min_total_memory, str):
         min_total_memory = human2bytes(min_total_memory)
 
-    available_devices = []  # type: Iterable[DeviceSnapshot]
+    available_devices = []
     for device in devices:
         available_devices.extend(dev.as_snapshot() for dev in device.to_leaf_devices())
     for device in available_devices:
@@ -261,20 +260,16 @@ def select_devices(
 
     if format == 'device':
         return [device.real for device in available_devices]
-
     if format == 'uuid':
-        identifiers = [device.uuid for device in available_devices]  # type: List[str]
-    else:
-        identifiers = [
-            device.index for device in available_devices
-        ]  # type: List[int, Tuple[int, int]]
-    return identifiers
+        return [device.uuid for device in available_devices]
+    return [device.index for device in available_devices]
 
 
-def parse_arguments():  # pylint: disable=too-many-branches,too-many-statements
+# pylint: disable-next=too-many-branches,too-many-statements
+def parse_arguments() -> argparse.Namespace:
     """Parse command-line arguments for ``nvisel``."""
 
-    def non_negint(argstring):
+    def non_negint(argstring: str) -> int:
         num = int(argstring)
         if num < 0:
             raise ValueError
@@ -489,7 +484,7 @@ def parse_arguments():  # pylint: disable=too-many-branches,too-many-statements
     return args
 
 
-def main():
+def main() -> None:
     """Main function for ``nvisel`` CLI."""
     args = parse_arguments()