diff --git a/src/borg/conftest.py b/src/borg/conftest.py
index 176003816..e9a749c1f 100644
--- a/src/borg/conftest.py
+++ b/src/borg/conftest.py
@@ -14,7 +14,7 @@ from borg.archiver import Archiver  # noqa: E402
 from borg.testsuite import has_lchflags, has_llfuse, has_pyfuse3  # noqa: E402
 from borg.testsuite import are_symlinks_supported, are_hardlinks_supported, is_utime_fully_supported  # noqa: E402
 from borg.testsuite.archiver import BORG_EXES
-from borg.testsuite.platform_test import fakeroot_detected  # noqa: E402
+from borg.testsuite.platform.platform_test import fakeroot_detected  # noqa: E402
 
 
 @pytest.fixture(autouse=True)
diff --git a/src/borg/selftest.py b/src/borg/selftest.py
index 0acbee19f..3a08d5be8 100644
--- a/src/borg/selftest.py
+++ b/src/borg/selftest.py
@@ -21,7 +21,7 @@ import sys
 import time
 from unittest import TestResult, TestSuite, defaultTestLoader
 
-from .testsuite.crypto_test import CryptoTestCase
+from .testsuite.crypto.crypto_test import CryptoTestCase
 from .testsuite.chunkers.buzhash_self_test import ChunkerTestCase
 from .testsuite.chunkers.fixed_self_test import ChunkerFixedTestCase
 
diff --git a/src/borg/testsuite/archiver/__init__.py b/src/borg/testsuite/archiver/__init__.py
index c3620a50b..180f1f013 100644
--- a/src/borg/testsuite/archiver/__init__.py
+++ b/src/borg/testsuite/archiver/__init__.py
@@ -29,7 +29,7 @@ from ...repository import Repository
 from .. import has_lchflags, is_utime_fully_supported, have_fuse_mtime_ns, st_mtime_ns_round, no_selinux
 from .. import changedir
 from .. import are_symlinks_supported, are_hardlinks_supported, are_fifos_supported
-from ..platform_test import is_win32
+from ..platform.platform_test import is_win32
 from ...xattr import get_all
 
 RK_ENCRYPTION = "--encryption=repokey-aes-ocb"
diff --git a/src/borg/testsuite/archiver/key_cmds_test.py b/src/borg/testsuite/archiver/key_cmds_test.py
index 79d933f22..173d92a1f 100644
--- a/src/borg/testsuite/archiver/key_cmds_test.py
+++ b/src/borg/testsuite/archiver/key_cmds_test.py
@@ -10,7 +10,7 @@ from ...helpers import CommandError
 from ...helpers import bin_to_hex, hex_to_bin
 from ...helpers import msgpack
 from ...repository import Repository
-from ..key_test import TestKey
+from ..crypto.key_test import TestKey
 from . import RK_ENCRYPTION, KF_ENCRYPTION, cmd, _extract_repository_id, _set_repository_id, generate_archiver_tests
 
 pytest_generate_tests = lambda metafunc: generate_archiver_tests(metafunc, kinds="local,remote,binary")  # NOQA
diff --git a/src/borg/testsuite/archiver/mount_cmds_test.py b/src/borg/testsuite/archiver/mount_cmds_test.py
index 59dcda11b..45623af1e 100644
--- a/src/borg/testsuite/archiver/mount_cmds_test.py
+++ b/src/borg/testsuite/archiver/mount_cmds_test.py
@@ -12,7 +12,7 @@ from ...helpers import flags_noatime, flags_normal
 from .. import has_lchflags, llfuse
 from .. import changedir, no_selinux, same_ts_ns
 from .. import are_symlinks_supported, are_hardlinks_supported, are_fifos_supported
-from ..platform_test import fakeroot_detected
+from ..platform.platform_test import fakeroot_detected
 from . import RK_ENCRYPTION, cmd, assert_dirs_equal, create_regular_file, create_src_archive, open_archive, src_file
 from . import requires_hardlinks, _extract_hardlinks_setup, fuse_mount, create_test_files, generate_archiver_tests
 
diff --git a/src/borg/testsuite/archiver/transfer_cmd_test.py b/src/borg/testsuite/archiver/transfer_cmd_test.py
index 7ac3df4bd..39d570d76 100644
--- a/src/borg/testsuite/archiver/transfer_cmd_test.py
+++ b/src/borg/testsuite/archiver/transfer_cmd_test.py
@@ -13,7 +13,7 @@ from ...constants import *  # NOQA
 from ...helpers import open_item
 from ...helpers.time import parse_timestamp
 from ...helpers.parseformat import parse_file_size, ChunkerParams
-from ..platform_test import is_win32
+from ..platform.platform_test import is_win32
 from . import cmd, create_regular_file, create_test_files, RK_ENCRYPTION, open_archive, generate_archiver_tests
 
 pytest_generate_tests = lambda metafunc: generate_archiver_tests(metafunc, kinds="local,remote")  # NOQA
diff --git a/src/borg/testsuite/cache_test.py b/src/borg/testsuite/cache_test.py
index e65735459..e6a5092ff 100644
--- a/src/borg/testsuite/cache_test.py
+++ b/src/borg/testsuite/cache_test.py
@@ -3,7 +3,7 @@ import os
 import pytest
 
 from .hashindex_test import H
-from .key_test import TestKey
+from .crypto.key_test import TestKey
 from ..archive import Statistics
 from ..cache import AdHocWithFilesCache
 from ..crypto.key import AESOCBRepoKey
diff --git a/src/borg/testsuite/crypto/__init__.py b/src/borg/testsuite/crypto/__init__.py
new file mode 100644
index 000000000..e69de29bb
diff --git a/src/borg/testsuite/crypto_test.py b/src/borg/testsuite/crypto/crypto_test.py
similarity index 97%
rename from src/borg/testsuite/crypto_test.py
rename to src/borg/testsuite/crypto/crypto_test.py
index 7c6ba0b22..edaa8b9cf 100644
--- a/src/borg/testsuite/crypto_test.py
+++ b/src/borg/testsuite/crypto/crypto_test.py
@@ -4,14 +4,14 @@
 from unittest.mock import MagicMock
 import unittest
 
-from ..crypto.low_level import AES256_CTR_HMAC_SHA256, AES256_OCB, CHACHA20_POLY1305, UNENCRYPTED, IntegrityError
-from ..crypto.low_level import bytes_to_long, bytes_to_int, long_to_bytes
-from ..crypto.low_level import AES, hmac_sha256
+from ...crypto.low_level import AES256_CTR_HMAC_SHA256, AES256_OCB, CHACHA20_POLY1305, UNENCRYPTED, IntegrityError
+from ...crypto.low_level import bytes_to_long, bytes_to_int, long_to_bytes
+from ...crypto.low_level import AES, hmac_sha256
 from hashlib import sha256
-from ..crypto.key import CHPOKeyfileKey, AESOCBRepoKey, FlexiKey, KeyBase, PlaintextKey
-from ..helpers import msgpack, bin_to_hex
+from ...crypto.key import CHPOKeyfileKey, AESOCBRepoKey, FlexiKey, KeyBase, PlaintextKey
+from ...helpers import msgpack, bin_to_hex
 
-from . import BaseTestCase
+from .. import BaseTestCase
 
 
 class CryptoTestCase(BaseTestCase):
diff --git a/src/borg/testsuite/file_integrity_test.py b/src/borg/testsuite/crypto/file_integrity_test.py
similarity index 98%
rename from src/borg/testsuite/file_integrity_test.py
rename to src/borg/testsuite/crypto/file_integrity_test.py
index 95add54ef..052bad81c 100644
--- a/src/borg/testsuite/file_integrity_test.py
+++ b/src/borg/testsuite/crypto/file_integrity_test.py
@@ -1,6 +1,6 @@
 import pytest
 
-from ..crypto.file_integrity import DetachedIntegrityCheckedFile, FileIntegrityError
+from ...crypto.file_integrity import DetachedIntegrityCheckedFile, FileIntegrityError
 
 
 class TestReadIntegrityFile:
diff --git a/src/borg/testsuite/key_test.py b/src/borg/testsuite/crypto/key_test.py
similarity index 93%
rename from src/borg/testsuite/key_test.py
rename to src/borg/testsuite/crypto/key_test.py
index 14c46a0c4..ca2884e29 100644
--- a/src/borg/testsuite/key_test.py
+++ b/src/borg/testsuite/crypto/key_test.py
@@ -4,20 +4,20 @@ from unittest.mock import MagicMock
 
 import pytest
 
-from ..crypto.key import PlaintextKey, AuthenticatedKey, Blake2AuthenticatedKey
-from ..crypto.key import RepoKey, KeyfileKey, Blake2RepoKey, Blake2KeyfileKey
-from ..crypto.key import AEADKeyBase
-from ..crypto.key import AESOCBRepoKey, AESOCBKeyfileKey, CHPORepoKey, CHPOKeyfileKey
-from ..crypto.key import Blake2AESOCBRepoKey, Blake2AESOCBKeyfileKey, Blake2CHPORepoKey, Blake2CHPOKeyfileKey
-from ..crypto.key import ID_HMAC_SHA_256, ID_BLAKE2b_256
-from ..crypto.key import UnsupportedManifestError, UnsupportedKeyFormatError
-from ..crypto.key import identify_key
-from ..crypto.low_level import IntegrityError as IntegrityErrorBase
-from ..helpers import IntegrityError
-from ..helpers import Location
-from ..helpers import msgpack
-from ..constants import KEY_ALGORITHMS
-from ..helpers import hex_to_bin, bin_to_hex
+from ...crypto.key import PlaintextKey, AuthenticatedKey, Blake2AuthenticatedKey
+from ...crypto.key import RepoKey, KeyfileKey, Blake2RepoKey, Blake2KeyfileKey
+from ...crypto.key import AEADKeyBase
+from ...crypto.key import AESOCBRepoKey, AESOCBKeyfileKey, CHPORepoKey, CHPOKeyfileKey
+from ...crypto.key import Blake2AESOCBRepoKey, Blake2AESOCBKeyfileKey, Blake2CHPORepoKey, Blake2CHPOKeyfileKey
+from ...crypto.key import ID_HMAC_SHA_256, ID_BLAKE2b_256
+from ...crypto.key import UnsupportedManifestError, UnsupportedKeyFormatError
+from ...crypto.key import identify_key
+from ...crypto.low_level import IntegrityError as IntegrityErrorBase
+from ...helpers import IntegrityError
+from ...helpers import Location
+from ...helpers import msgpack
+from ...constants import KEY_ALGORITHMS
+from ...helpers import hex_to_bin, bin_to_hex
 
 
 class TestKey:
diff --git a/src/borg/testsuite/efficient_collection_queue_test.py b/src/borg/testsuite/helpers/efficient_collection_queue_test.py
similarity index 96%
rename from src/borg/testsuite/efficient_collection_queue_test.py
rename to src/borg/testsuite/helpers/efficient_collection_queue_test.py
index aab2cf9b2..e80b11b90 100644
--- a/src/borg/testsuite/efficient_collection_queue_test.py
+++ b/src/borg/testsuite/helpers/efficient_collection_queue_test.py
@@ -1,6 +1,6 @@
 import pytest
 
-from ..helpers.datastruct import EfficientCollectionQueue
+from ...helpers.datastruct import EfficientCollectionQueue
 
 
 class TestEfficientQueue:
diff --git a/src/borg/testsuite/lrucache_test.py b/src/borg/testsuite/helpers/lrucache_test.py
similarity index 97%
rename from src/borg/testsuite/lrucache_test.py
rename to src/borg/testsuite/helpers/lrucache_test.py
index a3b13c1b7..8897702f2 100644
--- a/src/borg/testsuite/lrucache_test.py
+++ b/src/borg/testsuite/helpers/lrucache_test.py
@@ -2,7 +2,7 @@ from tempfile import TemporaryFile
 
 import pytest
 
-from ..helpers.lrucache import LRUCache
+from ...helpers.lrucache import LRUCache
 
 
 class TestLRUCache:
diff --git a/src/borg/testsuite/nanorst_test.py b/src/borg/testsuite/helpers/nanorst_test.py
similarity index 95%
rename from src/borg/testsuite/nanorst_test.py
rename to src/borg/testsuite/helpers/nanorst_test.py
index dc2f4f848..dad408db0 100644
--- a/src/borg/testsuite/nanorst_test.py
+++ b/src/borg/testsuite/helpers/nanorst_test.py
@@ -1,6 +1,6 @@
 import pytest
 
-from ..helpers.nanorst import rst_to_text
+from ...helpers.nanorst import rst_to_text
 
 
 def test_inline():
diff --git a/src/borg/testsuite/platform/__init__.py b/src/borg/testsuite/platform/__init__.py
new file mode 100644
index 000000000..e69de29bb
diff --git a/src/borg/testsuite/platform_darwin_test.py b/src/borg/testsuite/platform/darwin_test.py
similarity index 97%
rename from src/borg/testsuite/platform_darwin_test.py
rename to src/borg/testsuite/platform/darwin_test.py
index ca816c561..900355300 100644
--- a/src/borg/testsuite/platform_darwin_test.py
+++ b/src/borg/testsuite/platform/darwin_test.py
@@ -1,7 +1,7 @@
 import os
 import tempfile
 
-from ..platform import acl_get, acl_set
+from ...platform import acl_get, acl_set
 from .platform_test import skipif_not_darwin, skipif_fakeroot_detected, skipif_acls_not_working
 
 # set module-level skips
diff --git a/src/borg/testsuite/platform_freebsd_test.py b/src/borg/testsuite/platform/freebsd_test.py
similarity index 98%
rename from src/borg/testsuite/platform_freebsd_test.py
rename to src/borg/testsuite/platform/freebsd_test.py
index b86588230..c64c544ee 100644
--- a/src/borg/testsuite/platform_freebsd_test.py
+++ b/src/borg/testsuite/platform/freebsd_test.py
@@ -1,7 +1,7 @@
 import os
 import tempfile
 
-from ..platform import acl_get, acl_set
+from ...platform import acl_get, acl_set
 from .platform_test import skipif_not_freebsd, skipif_acls_not_working
 
 # set module-level skips
diff --git a/src/borg/testsuite/platform_linux_test.py b/src/borg/testsuite/platform/linux_test.py
similarity index 97%
rename from src/borg/testsuite/platform_linux_test.py
rename to src/borg/testsuite/platform/linux_test.py
index 8700e9d2b..6e760952a 100644
--- a/src/borg/testsuite/platform_linux_test.py
+++ b/src/borg/testsuite/platform/linux_test.py
@@ -1,7 +1,7 @@
 import os
 import tempfile
 
-from ..platform import acl_get, acl_set
+from ...platform import acl_get, acl_set
 from .platform_test import skipif_not_linux, skipif_fakeroot_detected, skipif_acls_not_working, skipif_no_ubel_user
 
 # set module-level skips
@@ -116,7 +116,7 @@ def test_non_ascii_acl():
 
 
 def test_utils():
-    from ..platform.linux import acl_use_local_uid_gid
+    from ...platform.linux import acl_use_local_uid_gid
 
     assert acl_use_local_uid_gid(b"user:nonexistent1234:rw-:1234") == b"user:1234:rw-"
     assert acl_use_local_uid_gid(b"group:nonexistent1234:rw-:1234") == b"group:1234:rw-"
diff --git a/src/borg/testsuite/platform_test.py b/src/borg/testsuite/platform/platform_test.py
similarity index 91%
rename from src/borg/testsuite/platform_test.py
rename to src/borg/testsuite/platform/platform_test.py
index 725d00511..4c763d8f9 100644
--- a/src/borg/testsuite/platform_test.py
+++ b/src/borg/testsuite/platform/platform_test.py
@@ -4,11 +4,11 @@ import os
 
 import pytest
 
-from ..platformflags import is_darwin, is_freebsd, is_linux, is_win32
-from ..platform import acl_get, acl_set
-from ..platform import get_process_id, process_alive
-from . import unopened_tempfile
-from .fslocking_test import free_pid  # NOQA
+from ...platformflags import is_darwin, is_freebsd, is_linux, is_win32
+from ...platform import acl_get, acl_set
+from ...platform import get_process_id, process_alive
+from .. import unopened_tempfile
+from ..fslocking_test import free_pid  # NOQA
 
 
 def fakeroot_detected():
@@ -77,7 +77,7 @@ skipif_acls_not_working = pytest.mark.skipif(not are_acls_working(), reason="ACL
 skipif_no_ubel_user = pytest.mark.skipif(not user_exists("übel"), reason="requires übel user")
 
 
-def test_process_alive(free_pid):
+def test_process_alive(free_pid):  # NOQA
     id = get_process_id()
     assert process_alive(*id)
     host, pid, tid = id
diff --git a/src/borg/testsuite/platform_posix_test.py b/src/borg/testsuite/platform/posix_test.py
similarity index 91%
rename from src/borg/testsuite/platform_posix_test.py
rename to src/borg/testsuite/platform/posix_test.py
index f9328b949..7e97d084f 100644
--- a/src/borg/testsuite/platform_posix_test.py
+++ b/src/borg/testsuite/platform/posix_test.py
@@ -1,4 +1,4 @@
-from ..platform import swidth
+from ...platform import swidth
 from .platform_test import skipif_not_posix
 
 
diff --git a/src/borg/testsuite/remote_test.py b/src/borg/testsuite/remote_test.py
index 26b57e197..aeb0b33c7 100644
--- a/src/borg/testsuite/remote_test.py
+++ b/src/borg/testsuite/remote_test.py
@@ -14,7 +14,7 @@ from ..helpers import IntegrityError
 from ..repoobj import RepoObj
 from .hashindex_test import H
 from .repository_test import fchunk, pdchunk
-from .key_test import TestKey
+from .crypto.key_test import TestKey
 
 
 class TestSleepingBandwidthLimiter: