"""The multi-backend dispatch substrate.

Two tuple-keyed registries (``COMPONENTS``, ``KERNELS``) + a ``Platform`` that detects ``(device,
arch)`` and resolves both, with the numpy reference as the terminal fallback rung and parity oracle.
Lets CPU, GPU, and other backends coexist: a model's loops, policies, scheduler, caches, and
training code never name a device; they call through the component/kernel seams and the resolved
``Platform`` decides the implementation.

Importing this package is cheap and cycle-free (registry + platform classes only); the concrete
backend registrations in ``backends/`` are imported lazily on first ``Platform`` use.
"""
from __future__ import annotations

from v2.platform.platform import (
    KernelTable,
    Platform,
    component_matrix,
    ensure_backends_loaded,
    kernel_matrix,
)
from v2.platform.registry import (
    COMPONENTS,
    FLOW_MATCH_STEP,
    FLOW_SDE_STEP,
    KERNELS,
    register_component,
    register_kernel,
)

__all__ = [
    "Platform",
    "KernelTable",
    "COMPONENTS",
    "KERNELS",
    "register_component",
    "register_kernel",
    "ensure_backends_loaded",
    "kernel_matrix",
    "component_matrix",
    "FLOW_MATCH_STEP",
    "FLOW_SDE_STEP",
]