diff --git a/pyunitwizard/__init__.py b/pyunitwizard/__init__.py
index de39de2..72f76ca 100644
--- a/pyunitwizard/__init__.py
+++ b/pyunitwizard/__init__.py
@@ -1,15 +1,22 @@
-"""
-PyUnitWizard
-Quantities and units assistant
-"""
+"""PyUnitWizard
+Quantities and units assistant."""
+
+from __future__ import annotations
+
+import sys
+import types
+import warnings
 
 # versioningit
 from ._version import __version__
 
-def __print_version__():
+
+def __print_version__() -> None:
     print("PyUnitWizard version " + __version__)
 
 
+from . import api as _api
+
 # Add imports here
 from .api import (
     are_close,
@@ -39,6 +46,46 @@ def __print_version__():
 from . import constants
 from . import utils
 
+__all__ = list(_api.__all__)
+
+
+def _create_main_compat_module() -> types.ModuleType:
+    module = types.ModuleType(
+        "pyunitwizard.main",
+        """Compatibility module for historic imports.
+
+        Deprecated in favour of importing from :mod:`pyunitwizard` directly.
+        """.strip(),
+    )
+    warned = False
+
+    def _emit_warning() -> None:
+        nonlocal warned
+        if not warned:
+            warnings.warn(
+                "Importing from 'pyunitwizard.main' is deprecated; import from 'pyunitwizard' instead.",
+                DeprecationWarning,
+                stacklevel=3,
+            )
+            warned = True
+
+    def __getattr__(name: str) -> object:
+        if name in _api.__all__:
+            _emit_warning()
+            return getattr(_api, name)
+        raise AttributeError(f"module 'pyunitwizard.main' has no attribute {name!r}")
+
+    def __dir__() -> list[str]:
+        return sorted(__all__)
+
+    module.__getattr__ = __getattr__  # type: ignore[assignment]
+    module.__dir__ = __dir__  # type: ignore[assignment]
+    module.__all__ = tuple(__all__)
+    return module
+
+
+sys.modules.setdefault("pyunitwizard.main", _create_main_compat_module())
+
 _kernel.initialize()
 
 try:
diff --git a/pyunitwizard/main.py b/pyunitwizard/main.py
deleted file mode 100644
index b161610..0000000
--- a/pyunitwizard/main.py
+++ /dev/null
@@ -1,47 +0,0 @@
-"""Compatibility module that re-exports the public API from :mod:`pyunitwizard.api`."""
-
-from __future__ import annotations
-
-from .api.comparison import (
-    are_close,
-    are_compatible,
-    are_equal,
-    compatibility,
-    similarity,
-)
-from .api.construction import quantity, unit
-from .api.conversion import convert, to_string
-from .api.extraction import change_value, get_unit, get_value, get_value_and_unit
-from .api.introspection import (
-    get_dimensionality,
-    get_form,
-    is_dimensionless,
-    is_quantity,
-    is_unit,
-)
-from .api.standardization import get_standard_units, standardize
-from .api.validation import check
-
-__all__ = [
-    "are_close",
-    "are_compatible",
-    "are_equal",
-    "change_value",
-    "check",
-    "compatibility",
-    "convert",
-    "get_dimensionality",
-    "get_form",
-    "get_standard_units",
-    "get_unit",
-    "get_value",
-    "get_value_and_unit",
-    "is_dimensionless",
-    "is_quantity",
-    "is_unit",
-    "quantity",
-    "similarity",
-    "standardize",
-    "to_string",
-    "unit",
-]
diff --git a/pyunitwizard/utils/sequences/is_sequence.py b/pyunitwizard/utils/sequences/is_sequence.py
index 496193d..423e00a 100644
--- a/pyunitwizard/utils/sequences/is_sequence.py
+++ b/pyunitwizard/utils/sequences/is_sequence.py
@@ -1,4 +1,8 @@
-from ...main import is_quantity
+"""Helpers to determine whether objects behave like sequences."""
+
+from __future__ import annotations
+
+from ... import is_quantity
 import numpy as np
 
 def is_sequence(item):