diff --git a/.github/scripts/check_template_versions.py b/.github/scripts/check_template_versions.py
index b18d607..9cdf010 100644
--- a/.github/scripts/check_template_versions.py
+++ b/.github/scripts/check_template_versions.py
@@ -8,7 +8,7 @@
 ------------------------------------------------
 1. Create the ``5.4.x`` branch from ``5.3.x`` and make it the default branch of the template repository.
 2. On it, raise the floors in pyproject.toml (``pymodaq>=5.4.0``...), the "PyMoDAQ 5.3.x" wording in README.rst and
-   AGENTS.md, the Python classifiers/requires-python and the matrix of reusable-compatibility.yml if they changed.
+   AGENTS.md, requires-python and the matrix of reusable-compatibility.yml if they changed.
 3. Point the three caller workflows (``@5.3.x`` in tests.yml, compatibility.yml, python-publish.yml) to ``@5.4.x``.
 4. Run this script: it must print OK. Keep ``5.3.x`` for hotfixes.
 """
@@ -78,11 +78,8 @@ def main() -> int:
     same_minor = [v for v in versions if minor(v) == branch_minor][-1]
     with urllib.request.urlopen(f'https://pypi.org/pypi/pymodaq/{same_minor}/json', timeout=30) as response:
         data = json.load(response)['info']
-    theirs = python_minors(data['classifiers'])
-    ours = python_minors(project['classifiers'])
-    if theirs and ours != theirs:
-        problems.append(f'Python classifiers of pyproject.toml are 3.{ours[0]}-3.{ours[-1]}, pymodaq {same_minor} says '
-                        f'3.{theirs[0]}-3.{theirs[-1]}')
+    # the Python classifiers of a plugin are computed from requires-python when it is built (dynamic classifiers)
+    ours = theirs = python_minors(data['classifiers'])
     requires = data.get('requires_python') or ''
     if requires and requires != project.get('requires-python'):
         problems.append(f'requires-python is {project.get("requires-python")!r}, pymodaq {same_minor} has {requires!r}')
diff --git a/AGENTS.md b/AGENTS.md
index c0806c0..fc1ef4a 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -58,6 +58,14 @@ File and class names must match: `daq_move_<Name>.py` holds `DAQ_Move_<Name>`; `
 to develop them. The list is defined once in `pymodaq_utils.plugin_tools.contract`, with when each method is called and
 what it returns (table in the developer guide, "The methods of a plugin").
 
+- (Actuators and detectors.) A plugin that works on some systems only (a Windows driver, a Raspberry Pi board)
+  declares it in the instrument class, for instance `supported_platforms = ('win32',)` (values of `sys.platform`:
+  `win32`, `linux`, `darwin`) and optionally `supported_architectures = ('aarch64', 'armv7l')` (values of
+  `platform.machine()`). PyMoDAQ then refuses to initialize it elsewhere with a message. The `Operating System` and
+  `Programming Language :: Python :: 3.x` classifiers are computed when the package is built (`classifiers` is
+  dynamic in the `pyproject.toml`, the others are in `[tool.pymodaq] classifiers`). A plugin working on several
+  systems must stay importable on all of them: import Windows-only code lazily (PMQ317; not reported when every
+  instrument is `('win32',)`). Needs `pymodaq>=5.3.6`.
 - `ini_stage(controller=None)` returns `(info: str, initialized: bool)`. If `self.is_master`, create the controller;
   otherwise store the `controller` passed in (several axes share one controller).
 - Class attributes: `is_multiaxes`, `_axis_names`, `_controller_units`, `_epsilons`,
diff --git a/pyproject.toml b/pyproject.toml
index 2db3617..c8de085 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -30,32 +30,16 @@ maintainers = [
 
 # nottodo: leave everything below as is!
 
-dynamic = ["version", "urls", "entry-points"]
+dynamic = ["version", "urls", "entry-points", "classifiers"]
 readme = "README.rst"
 license = { file="LICENSE" }
 requires-python = ">=3.10"
 
-classifiers = [
-    "Development Status :: 5 - Production/Stable",
-    "Intended Audience :: Science/Research",
-    "License :: OSI Approved :: MIT License",
-    "Natural Language :: English",
-    "Operating System :: OS Independent",
-    "Programming Language :: Python :: 3.10",
-    "Programming Language :: Python :: 3.11",
-    "Programming Language :: Python :: 3.12",
-    "Programming Language :: Python :: 3.13",
-    "Topic :: Scientific/Engineering :: Human Machine Interfaces",
-    "Topic :: Scientific/Engineering :: Visualization",
-    "Topic :: Software Development :: Libraries :: Python Modules",
-    "Topic :: Software Development :: User Interfaces",
-]
-
 [build-system]
 requires = [
     "hatchling>=1.9.0",
     "hatch-vcs", "toml",
-    "pymodaq_utils>=0.0.6",
+    "pymodaq_utils>=5.3.6",
 ]
 build-backend = "hatchling.build"
 
@@ -64,3 +48,16 @@ build-backend = "hatchling.build"
 [tool.hatch.version]
 source = "vcs"
 
+[tool.pymodaq]
+# the "Operating System" and "Programming Language :: Python :: 3.x" classifiers are added when building the package,
+# from supported_platforms in your instrument plugins and from requires-python
+classifiers = [
+    "Development Status :: 5 - Production/Stable",
+    "Intended Audience :: Science/Research",
+    "License :: OSI Approved :: MIT License",
+    "Natural Language :: English",
+    "Topic :: Scientific/Engineering :: Human Machine Interfaces",
+    "Topic :: Scientific/Engineering :: Visualization",
+    "Topic :: Software Development :: Libraries :: Python Modules",
+    "Topic :: Software Development :: User Interfaces",
+]