diff --git a/dascore/core/coordmanager.py b/dascore/core/coordmanager.py
index c57f54cb8..40d1d008c 100644
--- a/dascore/core/coordmanager.py
+++ b/dascore/core/coordmanager.py
@@ -42,7 +42,7 @@
 from __future__ import annotations
 
 from collections import defaultdict
-from collections.abc import Mapping, Sequence
+from collections.abc import Iterable, Mapping, Sequence
 from itertools import zip_longest
 from types import EllipsisType
 from typing import Annotated, Any
@@ -83,10 +83,14 @@
 )
 
 MaybeArray = ArrayLike | np.ndarray | None
-CoordManagerInput = Mapping[
-    str,
-    BaseCoord | np.ndarray | tuple[str | tuple[str, ...], BaseCoord | np.ndarray],
-]
+
+# What a coord map may hold, kept identical to the Patch constructor's coords.
+# The value stays Any on purpose: get_coord_manager also accepts an int or a
+# Quantity (a partial coord), a mapping of start/stop/step, and a
+# (dimension, data) tuple, and every union narrow enough to be worth writing
+# rejected one of those first-party forms. Mapping rather than dict so a
+# caller's narrower value type still matches.
+CoordManagerInput = Mapping[str, Any]
 
 
 def _ensure_1d_coord(coord, coord_name: str):
@@ -448,7 +452,7 @@ def new(self, dims=None, coord_map=None, dim_map=None, **kwargs) -> Self:
 
     def drop_coords(
         self,
-        *coords: str,
+        *coords: str | Iterable[str],
         array: MaybeArray = None,
     ) -> tuple[Self, MaybeArray]:
         """
@@ -460,10 +464,13 @@ def drop_coords(
         Parameters
         ----------
         *coords
-            The name of the coordinate or dimension.
+            The name of the coordinate or dimension, or a sequence of them.
         """
         dim_drop_list = []
-        coords_to_drop = {x for x in iterate(coords)}
+        # iterate is applied per argument; the varargs tuple is already
+        # iterable, so flattening it as a whole would leave any sequence
+        # passed in as a single unhashable element.
+        coords_to_drop = {x for coord in coords for x in iterate(coord)}
         # If there are either no coords to drop or this cm doesn't have them.
         if not coords_to_drop or not (set(self.coord_map) & coords_to_drop):
             return self, array
diff --git a/dascore/io/core.py b/dascore/io/core.py
index 3510f0d66..de2e8ca88 100644
--- a/dascore/io/core.py
+++ b/dascore/io/core.py
@@ -219,8 +219,10 @@ def _scan_payload_to_summary(
     payload: ScanPayload | Mapping[str, Any],
     *,
     source_path: str | Path | UPath | None = None,
-    source_format: str | None = None,
-    source_version: str | None = None,
+    # PatchSummary stores these as plain strings and its validator maps a
+    # missing value to "", so default to what it would normalize None to.
+    source_format: str = "",
+    source_version: str = "",
     source_patch_id: str | None = None,
 ) -> PatchSummary:
     """Convert one structured FiberIO scan payload into a PatchSummary."""
diff --git a/dascore/io/index/catalog.py b/dascore/io/index/catalog.py
index 181ebcb36..dee725bb0 100644
--- a/dascore/io/index/catalog.py
+++ b/dascore/io/index/catalog.py
@@ -474,8 +474,15 @@ def clear(self) -> None:
         self.value, self.revision = None, -1
 
 
-# sentinel: _view keeps the current order/ids spec unless told otherwise
-_KEEP = object()
+class _Keep:
+    """Sentinel: _view keeps the current order/ids spec unless told otherwise.
+
+    A dedicated class rather than a bare object so that testing against it
+    narrows the parameter to the spec type it otherwise holds.
+    """
+
+
+_KEEP = _Keep()
 
 
 class PatchCatalog:
@@ -702,7 +709,13 @@ def __getstate__(self) -> dict:
             state["resolver"] = _membership_resolver(resolver, keep, paths)
         return state
 
-    def _view(self, queries, residuals, order=_KEEP, ids=_KEEP) -> PatchCatalog:
+    def _view(
+        self,
+        queries,
+        residuals,
+        order: tuple | _Keep | None = _KEEP,
+        ids: tuple | _Keep | None = _KEEP,
+    ) -> PatchCatalog:
         out = PatchCatalog(
             backend=self.backend,
             resolver=self.resolver,
@@ -710,8 +723,8 @@ def _view(self, queries, residuals, order=_KEEP, ids=_KEEP) -> PatchCatalog:
             queries=queries,
             residuals=residuals,
             revision=self._revision,
-            order=self._order if order is _KEEP else order,
-            ids=self._ids if ids is _KEEP else ids,
+            order=self._order if isinstance(order, _Keep) else order,
+            ids=self._ids if isinstance(ids, _Keep) else ids,
             default_order=self._default_order,
         )
         return out
diff --git a/dascore/io/netcdf/utils.py b/dascore/io/netcdf/utils.py
index 733086aa2..d131a1ee5 100644
--- a/dascore/io/netcdf/utils.py
+++ b/dascore/io/netcdf/utils.py
@@ -2,7 +2,9 @@
 
 from __future__ import annotations
 
-import h5py
+from collections.abc import Mapping
+from typing import Any, Protocol
+
 import numpy as np
 
 import dascore as dc
@@ -32,7 +34,18 @@ def parse_cf_version(cf_version: str) -> tuple[int, int]:
     return major, minor
 
 
-def is_netcdf4_file(h5file: h5py.File) -> bool:
+class _HasAttrs(Protocol):
+    """Anything carrying HDF5-style attrs.
+
+    The two checks below only read `attrs`, and they are handed the managed
+    handle a FiberIO caster produces rather than an `h5py.File` proper.
+    """
+
+    @property
+    def attrs(self) -> Mapping[str, Any]: ...
+
+
+def is_netcdf4_file(h5file: _HasAttrs) -> bool:
     """Return True when an HDF5 file exposes strong NetCDF/CF markers."""
     try:
         if "_NCProperties" in h5file.attrs:
@@ -45,7 +58,7 @@ def is_netcdf4_file(h5file: h5py.File) -> bool:
         return False
 
 
-def get_cf_version(h5file: h5py.File) -> str | None:
+def get_cf_version(h5file: _HasAttrs) -> str | None:
     """Extract the CF convention version string from a NetCDF file."""
     conventions = h5file.attrs.get("Conventions", "")
     if isinstance(conventions, bytes):
diff --git a/dascore/proc/basic.py b/dascore/proc/basic.py
index 5a6dbe607..20bc32f1f 100644
--- a/dascore/proc/basic.py
+++ b/dascore/proc/basic.py
@@ -12,7 +12,11 @@
 from dascore.compat import array
 from dascore.constants import PatchType
 from dascore.core.attrs import PatchAttrs
-from dascore.core.coordmanager import CoordManager, get_coord_manager
+from dascore.core.coordmanager import (
+    CoordManager,
+    CoordManagerInput,
+    get_coord_manager,
+)
 from dascore.core.coords import get_coord
 from dascore.exceptions import ParameterError
 from dascore.utils.array import _apply_binary_ufunc
@@ -200,7 +204,7 @@ def bool_patch(self: PatchType):
 def update(
     self: PatchType,
     data: ArrayLike | np.ndarray | None = None,
-    coords: dict[str | Sequence[str], ArrayLike] | CoordManager | None = None,
+    coords: CoordManagerInput | CoordManager | None = None,
     dims: Sequence[str] | None = None,
     attrs: Mapping | PatchAttrs | None = None,
 ) -> PatchType:
diff --git a/dascore/proc/coords.py b/dascore/proc/coords.py
index 72b79e8bd..bbb3ce953 100644
--- a/dascore/proc/coords.py
+++ b/dascore/proc/coords.py
@@ -2,7 +2,7 @@
 
 from __future__ import annotations
 
-from collections.abc import Collection
+from collections.abc import Iterable
 
 import numpy as np
 import pandas as pd
@@ -260,7 +260,7 @@ def update_coords(self: PatchType, **kwargs) -> PatchType:
 
 
 @patch_function()
-def drop_coords(self: PatchType, *coords: str | Collection[str]) -> PatchType:
+def drop_coords(self: PatchType, *coords: str | Iterable[str]) -> PatchType:
     """
     Update the coordinates of a patch.
 
@@ -269,7 +269,8 @@ def drop_coords(self: PatchType, *coords: str | Collection[str]) -> PatchType:
     Parameters
     ----------
     *coords
-        One or more coordinates to drop.
+        One or more coordinates to drop. Each can be a coordinate name or
+        a sequence of them.
 
     Examples
     --------
@@ -278,11 +279,14 @@ def drop_coords(self: PatchType, *coords: str | Collection[str]) -> PatchType:
     >>> pa = dc.get_example_patch("random_patch_with_lat_lon")
     >>> # Drop non-dimensional coordinate latitude
     >>> pa_no_lat = pa.drop_coords("latitude")
+    >>> # A sequence of names works as well.
+    >>> pa_no_lat = pa.drop_coords(["latitude"])
     """
-    if dim_coords := set(coords) & set(self.dims):
+    names = {x for coord in coords for x in iterate(coord)}
+    if dim_coords := names & set(self.dims):
         msg = f"Cannot drop dimensional coordinates: {dim_coords}"
         raise ParameterError(msg)
-    new_coord, data = self.coords.drop_coords(*coords, array=self.data)
+    new_coord, data = self.coords.drop_coords(*names, array=self.data)
     return self.new(coords=new_coord, dims=new_coord.dims, data=data)
 
 
diff --git a/dascore/units.py b/dascore/units.py
index 21ab5dfcc..5e3261e24 100644
--- a/dascore/units.py
+++ b/dascore/units.py
@@ -7,7 +7,7 @@
 from functools import cache
 from threading import RLock
 from types import EllipsisType
-from typing import Any, TypeVar
+from typing import Any, TypeVar, cast
 
 import numpy as np
 import pandas as pd
@@ -520,7 +520,7 @@ def maybe_convert_percent_to_fraction(obj):
     return out
 
 
-def __getattr__(name):
+def __getattr__(name: str) -> Quantity:
     """
     Allows arbitrary units (quantities) to be imported from this module.
 
@@ -530,5 +530,12 @@ def __getattr__(name):
     is the same as
     from dascore.units import get_quantity
     m = get_quantity("m")
+
+    Any non-empty name either resolves to a quantity or raises
+    UndefinedUnitError, so the cast holds. The empty string is the one input
+    get_quantity maps to None, and attribute access is the right place to
+    reject it.
     """
-    return get_quantity(name)
+    if not name:
+        raise AttributeError(name)
+    return cast("Quantity", get_quantity(name))
diff --git a/dascore/utils/mapping.py b/dascore/utils/mapping.py
index 170e9f46b..900044197 100644
--- a/dascore/utils/mapping.py
+++ b/dascore/utils/mapping.py
@@ -41,9 +41,11 @@ def __contains__(self, key: object) -> bool:
 
     def new(self, **kwargs):
         """Copy the contents  and update with new values."""
+        # Passed as a mapping rather than splatted so keys that are not
+        # strings survive the round trip.
         contents = dict(self._dict)
         contents.update(kwargs)
-        return self.__class__(**contents)
+        return self.__class__(contents)
 
     def __iter__(self) -> Iterator[K]:
         return iter(self._dict)
diff --git a/dascore/utils/patch.py b/dascore/utils/patch.py
index 37dc23472..b9049a1d7 100644
--- a/dascore/utils/patch.py
+++ b/dascore/utils/patch.py
@@ -7,7 +7,7 @@
 import sys
 import warnings
 from collections import namedtuple
-from collections.abc import Callable, Mapping, Sequence
+from collections.abc import Callable, Iterable, Mapping, Sequence
 from typing import Any, Literal, Protocol, cast, overload
 
 import numpy as np
@@ -298,10 +298,14 @@ def patch_function(
       as dc at the top of the file where the patch function is defined so
       the forward refs can be resolved properly for type checking.
     """
+    # Handled before the wrapper is built so the rest of this function sees
+    # required_dims as the tuple of dimension names it is everywhere else.
+    if callable(required_dims):  # the decorator is used without parens
+        return patch_function()(required_dims)
 
     def _wrapper(func):
         if validate_call:
-            config = dict(arbitrary_types_allowed=True)
+            config = pydantic.ConfigDict(arbitrary_types_allowed=True)
             func = pydantic.validate_call(config=config)(func)
 
         @functools.wraps(func)
@@ -338,9 +342,6 @@ def _func(patch, *args, **kwargs):
 
         return patch_func
 
-    if callable(required_dims):  # the decorator is used without parens
-        return patch_function()(required_dims)
-
     return _wrapper
 
 
@@ -551,7 +552,12 @@ def get_start_stop_step(patch: PatchType, dim):
 
 
 def get_patch_names(
-    patch_data: pd.DataFrame | dc.Patch | dc.BaseSpool,
+    # Forwarded straight to scan_to_df, so anything it scans works here,
+    # including a plain list of patches. Spelled out rather than reusing
+    # io.core.ScanInput: importing that is circular, and hiding it behind
+    # TYPE_CHECKING leaves the annotation unresolvable at runtime, which
+    # breaks get_type_hints and the API doc renderer.
+    patch_data: pd.DataFrame | dc.Patch | dc.BaseSpool | Iterable[dc.Patch],
     prefix="DAS",
     attrs=("network", "station", "tag"),
     coords=("time",),
diff --git a/dascore/utils/patch_assembly.py b/dascore/utils/patch_assembly.py
index 643e66707..8b138182a 100644
--- a/dascore/utils/patch_assembly.py
+++ b/dascore/utils/patch_assembly.py
@@ -224,7 +224,10 @@ def _merge_patches_streaming(self, joined, df_dict_list, merge_dim, samples):
             coords.append(patch.coords)
             attrs.append(patch.attrs)
             summaries.append(patch.coords._get_dim_summary())
-        assert buffer is not None  # allocated on the first pass of the loop
+        # All set on the first pass of the loop, which always runs.
+        assert buffer is not None
+        assert axis is not None
+        assert dims is not None
         if offset != buffer.shape[axis]:  # over-estimated; trim excess.
             buffer = buffer[broadcast_for_index(buffer.ndim, axis, slice(0, offset))]
         # Ensure the loaded patches only vary along the expected dimension,
diff --git a/docs/changelog.qmd b/docs/changelog.qmd
index 711461c83..6b4d909cb 100644
--- a/docs/changelog.qmd
+++ b/docs/changelog.qmd
@@ -4,6 +4,7 @@ The [releases page](https://github.com/DASDAE/dascore/releases) tracks changes f
 
 ## Unreleased API Changes
 
+- `Patch.drop_coords` and `CoordManager.drop_coords` accept a sequence of names as well as bare names, so `patch.drop_coords(["latitude", "longitude"])` works alongside `patch.drop_coords("latitude", "longitude")`. Previously a list or set raised `TypeError` and a tuple or generator was silently ignored; a tuple now drops the named coordinates, and one naming a dimension raises `ParameterError` as a bare dimension name always has.
 - **Runtime configuration is now two-tier.** `dc.set_config(...)` sets the process-wide base permanently (visible from every thread and task) and returns the new config; it is no longer a context manager. Temporary, thread/task-local overrides use the new `dc.config_context(...)` context manager, which restores on exit and isolates concurrent overrides via a `ContextVar`. `Spool.map(...)` captures the config active at the call and re-applies it in each worker, so thread- and process-pool workers observe the caller's config regardless of the pool's start method. Unknown config field names now raise instead of being silently ignored. Migrate `with dc.set_config(...)` to `with dc.config_context(...)`.
 - PRODML 2.1 now supports writing one raw time-by-distance patch with `dc.write` as a standalone HDF5 file. Full PRODML 2.3 conformance requires EPC/XML packaging, which DASCore does not write.
 - **The `dascore.io.sintela_binary` module is removed (no alias).** Both Sintela readers now live in `dascore.io.sintela`, which also provides the new protobuf reader; use `from dascore.io.sintela import SintelaBinaryV3`. Reading Sintela binary files through `dc.read`/`dc.spool`/`dc.scan` is unaffected — only the direct module import path changed.
diff --git a/tests/test_core/test_coordmanager.py b/tests/test_core/test_coordmanager.py
index 1c271c13c..cdd8688a2 100644
--- a/tests/test_core/test_coordmanager.py
+++ b/tests/test_core/test_coordmanager.py
@@ -339,6 +339,16 @@ def test_drop_doesnt_have_coord(self, cm_multidim):
         out, _ = cm_multidim.drop_coords("bob")
         assert out == cm_multidim
 
+    @pytest.mark.parametrize("wrap", [list, tuple, set, iter])
+    def test_drop_sequence(self, cm_multidim, wrap):
+        """A sequence of names should behave exactly like the bare name."""
+        dim = "distance"
+        coords, _ = cm_multidim.drop_coords(wrap([dim]))
+        expected, _ = cm_multidim.drop_coords(dim)
+        assert dim not in coords.dims
+        # Compared to the bare-name call so that dropping too much fails too.
+        assert coords == expected
+
     def test_trims_array(self, cm_multidim):
         """Trying to drop a dim that doesnt exist should just return."""
         array = np.ones(cm_multidim.shape)
diff --git a/tests/test_proc/test_proc_coords.py b/tests/test_proc/test_proc_coords.py
index 4b2e31160..75b37d30b 100644
--- a/tests/test_proc/test_proc_coords.py
+++ b/tests/test_proc/test_proc_coords.py
@@ -154,6 +154,33 @@ def test_drop_dim_raises(self, random_patch):
         with pytest.raises(ParameterError, match=msg):
             random_patch.drop_coords("time")
 
+    @pytest.mark.parametrize(
+        "form", [["latitude"], ("latitude",), {"latitude"}, iter(["latitude"])]
+    )
+    def test_drop_sequence(self, random_patch_with_lat_lon, form):
+        """A sequence of names should behave exactly like the bare name."""
+        patch = random_patch_with_lat_lon
+        out = patch.drop_coords(form)
+        expected = patch.drop_coords("latitude")
+        assert "latitude" not in out.coords.coord_map
+        # Compared to the bare-name call so that dropping too much fails too.
+        assert set(out.coords.coord_map) == set(expected.coords.coord_map)
+
+    def test_drop_mixed_args(self, random_patch_with_lat_lon):
+        """Names and sequences of names should be usable together."""
+        patch = random_patch_with_lat_lon
+        out = patch.drop_coords("latitude", ["longitude"])
+        dropped = {"latitude", "longitude"}
+        assert not dropped & set(out.coords.coord_map)
+        # Everything else has to survive.
+        assert set(out.coords.coord_map) == set(patch.coords.coord_map) - dropped
+
+    def test_drop_dim_in_sequence_raises(self, random_patch):
+        """A dimension inside a sequence should raise like a bare one."""
+        msg = "Cannot drop dimensional coordinates"
+        with pytest.raises(ParameterError, match=msg):
+            random_patch.drop_coords(["time"])
+
 
 class TestCoordsFromDf:
     """Tests for attaching coordinate(s) to a patch."""
diff --git a/tests/test_units.py b/tests/test_units.py
index 6e32a887b..ac4a5b58e 100644
--- a/tests/test_units.py
+++ b/tests/test_units.py
@@ -222,6 +222,13 @@ def test_bad_import_error_msg(self):
         with pytest.raises(ImportError):
             from dascore.utils import bob  # noqa
 
+    def test_empty_name_raises(self):
+        """The empty string is the one name get_quantity maps to None."""
+        import dascore.units
+
+        with pytest.raises(AttributeError):
+            getattr(dascore.units, "")
+
 
 class TestGetFilterUnits:
     """Tests for getting units that can be used for filtering."""
diff --git a/tests/test_utils/test_mapping_utils.py b/tests/test_utils/test_mapping_utils.py
index bb3621bd0..bf31c5677 100644
--- a/tests/test_utils/test_mapping_utils.py
+++ b/tests/test_utils/test_mapping_utils.py
@@ -85,3 +85,8 @@ def test_new(self, frozen_dict):
         """Ensure new values can be added to the dict."""
         out = frozen_dict.new(bob=10)
         assert out["bob"] == 10
+
+    def test_new_keeps_non_string_keys(self):
+        """Keys that cannot be keyword arguments must survive new."""
+        froz = FrozenDict({1: "a", 2: "b"})
+        assert dict(froz.new()) == {1: "a", 2: "b"}
diff --git a/tests/test_utils/test_patch_utils.py b/tests/test_utils/test_patch_utils.py
index ec859be66..394192caa 100644
--- a/tests/test_utils/test_patch_utils.py
+++ b/tests/test_utils/test_patch_utils.py
@@ -838,6 +838,15 @@ def test_empty(self):
         out = get_patch_names([])
         assert isinstance(out, pd.Series)
 
+    def test_annotations_resolve(self):
+        """
+        The docs renderer resolves annotations at runtime and falls back to
+        raw strings for the whole signature if any name is undefined.
+        """
+        from typing import get_type_hints
+
+        assert get_type_hints(get_patch_names)
+
     def test_name_column_exists(self, random_spool):
         """If the name or path field already exist this should be used."""
         df = random_spool.get_contents().assign(name=lambda x: np.arange(len(x)))