diff --git a/docs/news.rst b/docs/news.rst
index 63f0d69e4..3964722c7 100644
--- a/docs/news.rst
+++ b/docs/news.rst
@@ -3,6 +3,28 @@
 Release notes
 =============
 
+Scrapy VERSION (unreleased)
+---------------------------
+
+Backward-incompatible changes
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+-   The following runtime usage of zope.interface_ interfaces is removed:
+
+    - :class:`~scrapy.spiderloader.SpiderLoader` and
+      :class:`~scrapy.spiderloader.DummySpiderLoader` are no longer marked
+      as implementing the ``ISpiderLoader`` interface.
+
+    - :func:`~scrapy.spiderloader.get_spider_loader` no longer checks that the
+      configured spider loader implements the ``ISpiderLoader`` interface.
+
+    - :class:`~scrapy.extensions.feedexport.BlockingFeedStorage`,
+    - :class:`~scrapy.extensions.feedexport.FileFeedStorage` and
+    - :class:`~scrapy.extensions.feedexport.StdoutFeedStorage` are no longer
+      marked as implementing the ``IFeedStorage`` interface.
+
+    (:issue:`6585`, :issue:`TBD`)
+
 .. _release-2.17.0:
 
 Scrapy 2.17.0 (2026-07-07)
@@ -2643,7 +2665,7 @@ Deprecation removals
     (:issue:`6109`, :issue:`6116`)
 
 -   A custom class assigned to the :setting:`SPIDER_LOADER_CLASS` setting that
-    does not implement the :class:`~scrapy.interfaces.ISpiderLoader` interface
+    does not implement the ``ISpiderLoader`` interface
     will now raise a :exc:`zope.interface.verify.DoesNotImplement` exception at
     run time. Non-compliant classes have been triggering a deprecation warning
     since Scrapy 1.0.0.
diff --git a/docs/topics/api.rst b/docs/topics/api.rst
index 19082d9d7..c80bbd539 100644
--- a/docs/topics/api.rst
+++ b/docs/topics/api.rst
@@ -178,9 +178,7 @@ SpiderLoader API
     defined across the project.
 
     Custom spider loaders can be employed by specifying their path in the
-    :setting:`SPIDER_LOADER_CLASS` project setting. They must fully implement
-    the :class:`scrapy.interfaces.ISpiderLoader` interface to guarantee an
-    errorless execution.
+    :setting:`SPIDER_LOADER_CLASS` project setting.
 
     .. method:: from_settings(settings)
 
diff --git a/scrapy/core/downloader/contextfactory.py b/scrapy/core/downloader/contextfactory.py
index a934cbbc7..ef948997d 100644
--- a/scrapy/core/downloader/contextfactory.py
+++ b/scrapy/core/downloader/contextfactory.py
@@ -13,7 +13,6 @@ from twisted.internet.ssl import (
 from twisted.web.client import BrowserLikePolicyForHTTPS
 from twisted.web.iweb import IPolicyForHTTPS
 from zope.interface.declarations import implementer
-from zope.interface.verify import verifyObject
 
 from scrapy.core.downloader.tls import (
     _TWISTED_VERSION_MAP,
@@ -232,7 +231,6 @@ class _AcceptableProtocolsContextFactory:
     # all of this with _ScrapyClientContextFactory.acceptableProtocols.
 
     def __init__(self, context_factory: Any, acceptable_protocols: list[bytes]):
-        verifyObject(IPolicyForHTTPS, context_factory)
         self._wrapped_context_factory: Any = context_factory
         self._acceptable_protocols: list[bytes] = acceptable_protocols
 
diff --git a/scrapy/extensions/feedexport.py b/scrapy/extensions/feedexport.py
index fa708a2e1..9c95e3331 100644
--- a/scrapy/extensions/feedexport.py
+++ b/scrapy/extensions/feedexport.py
@@ -22,7 +22,7 @@ from urllib.parse import unquote, urlparse
 
 from twisted.internet.defer import Deferred, DeferredList
 from w3lib.url import file_uri_to_path
-from zope.interface import Interface, implementer
+from zope.interface import Interface
 
 from scrapy import Spider, signals
 from scrapy.exceptions import NotConfigured, ScrapyDeprecationWarning
@@ -88,25 +88,18 @@ class ItemFilter:
         return True  # accept all items by default
 
 
-class IFeedStorage(Interface):  # type: ignore[misc]
-    """Interface that all Feed Storages must implement"""
-
+class _IFeedStorage(Interface):  # type: ignore[misc]  # pragma: no cover
     # pylint: disable=no-self-argument
 
-    def __init__(uri, *, feed_options=None):  # type: ignore[no-untyped-def]  # pylint: disable=super-init-not-called
-        """Initialize the storage with the parameters given in the URI and the
-        feed-specific options (see :setting:`FEEDS`)"""
+    def __init__(uri, *, feed_options=None): ...  # type: ignore[no-untyped-def]  # pylint: disable=super-init-not-called
 
-    def open(spider):  # type: ignore[no-untyped-def]
-        """Open the storage for the given spider. It must return a file-like
-        object that will be used for the exporters"""
+    def open(spider): ...  # type: ignore[no-untyped-def]
 
-    def store(file):  # type: ignore[no-untyped-def]
-        """Store the given file stream"""
+    def store(file): ...  # type: ignore[no-untyped-def]
 
 
 class FeedStorageProtocol(Protocol):
-    """Reimplementation of ``IFeedStorage`` that can be used in type hints."""
+    """Protocol that all Feed Storages must follow."""
 
     def __init__(self, uri: str, *, feed_options: dict[str, Any] | None = None):
         """Initialize the storage with the parameters given in the URI and the
@@ -120,7 +113,6 @@ class FeedStorageProtocol(Protocol):
         """Store the given file stream"""
 
 
-@implementer(IFeedStorage)
 class BlockingFeedStorage(ABC):
     def open(self, spider: Spider) -> IO[bytes]:
         path = spider.crawler.settings["FEED_TEMPDIR"]
@@ -137,7 +129,6 @@ class BlockingFeedStorage(ABC):
         raise NotImplementedError
 
 
-@implementer(IFeedStorage)
 class StdoutFeedStorage:
     def __init__(
         self,
@@ -164,7 +155,6 @@ class StdoutFeedStorage:
         pass
 
 
-@implementer(IFeedStorage)
 class FileFeedStorage:
     def __init__(self, uri: str, *, feed_options: dict[str, Any] | None = None):
         self.path: str = file_uri_to_path(uri) if uri.startswith("file:") else uri
@@ -731,3 +721,14 @@ class FeedExporter:
             feed_options.get("item_filter", ItemFilter)
         )
         return item_filter_class(feed_options)
+
+
+def __getattr__(name: str) -> Any:  # pragma: no cover
+    if name == "IFeedStorage":
+        warnings.warn(
+            "scrapy.extensions.feedexport.IFeedStorage is deprecated.",
+            ScrapyDeprecationWarning,
+            stacklevel=2,
+        )
+        return _IFeedStorage
+    raise AttributeError(f"module {__name__!r} has no attribute {name!r}")
diff --git a/scrapy/interfaces.py b/scrapy/interfaces.py
index b4f1d9394..34d7bdd82 100644
--- a/scrapy/interfaces.py
+++ b/scrapy/interfaces.py
@@ -1,19 +1,23 @@
+# pragma: no file cover
 # pylint: disable=no-method-argument,no-self-argument
+import warnings
 
 from zope.interface import Interface
 
+from scrapy.exceptions import ScrapyDeprecationWarning
+
+warnings.warn(
+    "The scrapy.interfaces module is deprecated.",
+    ScrapyDeprecationWarning,
+    stacklevel=2,
+)
+
 
 class ISpiderLoader(Interface):
-    def from_settings(settings):
-        """Return an instance of the class for the given settings"""
+    def from_settings(settings): ...
 
-    def load(spider_name):
-        """Return the Spider class for the given spider name. If the spider
-        name is not found, it must raise a KeyError."""
+    def load(spider_name): ...
 
-    def list():
-        """Return a list with the names of all spiders available in the
-        project"""
+    def list(): ...
 
-    def find_by_request(request):
-        """Return the list of spiders names that can handle the given request"""
+    def find_by_request(request): ...
diff --git a/scrapy/spiderloader.py b/scrapy/spiderloader.py
index 8c980fd46..d98e1a5a0 100644
--- a/scrapy/spiderloader.py
+++ b/scrapy/spiderloader.py
@@ -5,10 +5,6 @@ import warnings
 from collections import defaultdict
 from typing import TYPE_CHECKING, Protocol, cast
 
-from zope.interface import implementer
-from zope.interface.verify import verifyClass
-
-from scrapy.interfaces import ISpiderLoader
 from scrapy.utils.misc import load_object, walk_modules_iter
 from scrapy.utils.spider import iter_spider_classes
 
@@ -26,7 +22,6 @@ def get_spider_loader(settings: BaseSettings) -> SpiderLoaderProtocol:
     """Get SpiderLoader instance from settings"""
     cls_path = settings.get("SPIDER_LOADER_CLASS")
     loader_cls = load_object(cls_path)
-    verifyClass(ISpiderLoader, loader_cls)
     return cast("SpiderLoaderProtocol", loader_cls.from_settings(settings.frozencopy()))
 
 
@@ -47,7 +42,6 @@ class SpiderLoaderProtocol(Protocol):
         """Return the list of spiders names that can handle the given request"""
 
 
-@implementer(ISpiderLoader)
 class SpiderLoader:
     """
     SpiderLoader is a class which locates and loads spiders
@@ -133,7 +127,6 @@ class SpiderLoader:
         return list(self._spiders.keys())
 
 
-@implementer(ISpiderLoader)
 class DummySpiderLoader:
     """A dummy spider loader that does not load any spiders."""
 
diff --git a/tests/test_crawler.py b/tests/test_crawler.py
index 6a1eea027..5106c890e 100644
--- a/tests/test_crawler.py
+++ b/tests/test_crawler.py
@@ -10,7 +10,6 @@ from typing import TYPE_CHECKING, Any, ClassVar
 from unittest.mock import MagicMock
 
 import pytest
-from zope.interface.exceptions import MultipleInvalid
 
 import scrapy
 from scrapy import Spider
@@ -586,21 +585,7 @@ class TestCrawlerLogging:
         assert "debug message" in logged
 
 
-class SpiderLoaderWithWrongInterface:
-    def unneeded_method(self) -> None:
-        pass
-
-
 class TestCrawlerRunner(TestBaseCrawler):
-    def test_spider_manager_verify_interface(self) -> None:
-        settings = Settings(
-            {
-                "SPIDER_LOADER_CLASS": SpiderLoaderWithWrongInterface,
-            }
-        )
-        with pytest.raises(MultipleInvalid):
-            CrawlerRunner(settings)
-
     def test_crawler_runner_accepts_dict(self) -> None:
         runner = CrawlerRunner({"foo": "bar"})
         assert runner.settings["foo"] == "bar"
@@ -612,15 +597,6 @@ class TestCrawlerRunner(TestBaseCrawler):
 
 
 class TestAsyncCrawlerRunner(TestBaseCrawler):
-    def test_spider_manager_verify_interface(self) -> None:
-        settings = Settings(
-            {
-                "SPIDER_LOADER_CLASS": SpiderLoaderWithWrongInterface,
-            }
-        )
-        with pytest.raises(MultipleInvalid):
-            AsyncCrawlerRunner(settings)
-
     def test_crawler_runner_accepts_dict(self) -> None:
         runner = AsyncCrawlerRunner({"foo": "bar"})
         assert runner.settings["foo"] == "bar"
diff --git a/tests/test_feedexport.py b/tests/test_feedexport.py
index 7d751f188..557c4bb1b 100644
--- a/tests/test_feedexport.py
+++ b/tests/test_feedexport.py
@@ -20,7 +20,6 @@ import lxml.etree
 import pytest
 from testfixtures import LogCapture
 from w3lib.url import file_uri_to_path
-from zope.interface import implementer
 
 import scrapy
 from scrapy import Spider, signals
@@ -31,7 +30,6 @@ from scrapy.extensions.feedexport import (
     FeedExporter,
     FeedSlot,
     FileFeedStorage,
-    IFeedStorage,
 )
 from scrapy.utils.python import to_unicode
 from scrapy.utils.test import get_crawler
@@ -91,7 +89,6 @@ class FailingBlockingFeedStorage(DummyBlockingFeedStorage):
         raise OSError("Cannot store")
 
 
-@implementer(IFeedStorage)
 class LogOnStoreFileStorage:
     """
     This storage logs inside `store` method.
@@ -1234,7 +1231,6 @@ class TestFeedExport(TestFeedExportBase):
 
     @coroutine_test
     async def test_storage_file_no_postprocessing(self):
-        @implementer(IFeedStorage)
         class Storage:
             def __init__(self, uri, *, feed_options=None):
                 pass
@@ -1256,7 +1252,6 @@ class TestFeedExport(TestFeedExportBase):
 
     @coroutine_test
     async def test_storage_file_postprocessing(self):
-        @implementer(IFeedStorage)
         class Storage:
             def __init__(self, uri, *, feed_options=None):
                 pass
diff --git a/tests/test_feedexport_batch.py b/tests/test_feedexport_batch.py
index 469985288..a7547a30c 100644
--- a/tests/test_feedexport_batch.py
+++ b/tests/test_feedexport_batch.py
@@ -12,12 +12,11 @@ from urllib.parse import urljoin
 import lxml.etree
 import pytest
 from packaging.version import Version
-from zope.interface.verify import verifyObject
 
 import scrapy
 from scrapy import Spider
 from scrapy.exceptions import NotConfigured
-from scrapy.extensions.feedexport import FeedExporter, IFeedStorage, S3FeedStorage
+from scrapy.extensions.feedexport import FeedExporter, S3FeedStorage
 from scrapy.settings import Settings
 from scrapy.utils.python import to_unicode
 from scrapy.utils.test import get_crawler
@@ -435,9 +434,6 @@ class TestBatchDeliveries(TestFeedExportBase):
                 },
             },
         }
-        crawler = get_crawler(settings_dict=settings)
-        storage = S3FeedStorage.from_crawler(crawler, uri)
-        verifyObject(IFeedStorage, storage)
 
         class TestSpider(scrapy.Spider):
             name = "testspider"
diff --git a/tests/test_feedexport_storages.py b/tests/test_feedexport_storages.py
index 11e79775f..cddbc5f97 100644
--- a/tests/test_feedexport_storages.py
+++ b/tests/test_feedexport_storages.py
@@ -12,7 +12,6 @@ from urllib.parse import quote
 import pytest
 from testfixtures import LogCapture
 from w3lib.url import path_to_file_uri
-from zope.interface.verify import verifyObject
 
 import scrapy
 from scrapy.extensions.feedexport import (
@@ -20,7 +19,6 @@ from scrapy.extensions.feedexport import (
     FileFeedStorage,
     FTPFeedStorage,
     GCSFeedStorage,
-    IFeedStorage,
     S3FeedStorage,
     StdoutFeedStorage,
 )
@@ -71,11 +69,6 @@ class TestFileFeedStorage:
         finally:
             os.chdir(old_cwd)
 
-    def test_interface(self, tmp_path):
-        path = tmp_path / "file.txt"
-        st = FileFeedStorage(str(path))
-        verifyObject(IFeedStorage, st)
-
     @staticmethod
     def _store(path: Path, feed_options: dict[str, Any] | None = None) -> None:
         storage = FileFeedStorage(str(path), feed_options=feed_options)
@@ -131,7 +124,6 @@ class TestFTPFeedStorage:
             uri,
             feed_options=feed_options,
         )
-        verifyObject(IFeedStorage, storage)
         spider = self.get_test_spider()
         file = storage.open(spider)
         file.write(content)
@@ -275,7 +267,6 @@ class TestS3FeedStorage:
         bucket = "mybucket"
         key = "export.csv"
         storage = S3FeedStorage.from_crawler(crawler, f"s3://{bucket}/{key}")
-        verifyObject(IFeedStorage, storage)
 
         file = mock.MagicMock()
 
diff --git a/tests/test_spiderloader/__init__.py b/tests/test_spiderloader/__init__.py
index d85942f90..8974cec89 100644
--- a/tests/test_spiderloader/__init__.py
+++ b/tests/test_spiderloader/__init__.py
@@ -5,14 +5,12 @@ from pathlib import Path
 from unittest import mock
 
 import pytest
-from zope.interface.verify import verifyObject
 
 # ugly hack to avoid cyclic imports of scrapy.spiders when running this test
 # alone
 import scrapy
 from scrapy.crawler import CrawlerRunner
 from scrapy.http import Request
-from scrapy.interfaces import ISpiderLoader
 from scrapy.settings import Settings
 from scrapy.spiderloader import DummySpiderLoader, SpiderLoader, get_spider_loader
 
@@ -45,9 +43,6 @@ def spider_loader(spider_loader_env):
 
 
 class TestSpiderLoader:
-    def test_interface(self, spider_loader):
-        verifyObject(ISpiderLoader, spider_loader)
-
     def test_list(self, spider_loader):
         assert set(spider_loader.list()) == {
             "spider1",