Trusted executable transport

Normal pickle works by reference for importable Config classes. Install the transport extra when notebook-local classes or interpolation lambdas must cross a process boundary:

pip install --pre 'nshconfig[transport]'

import cloudpickle


work = Run.config_draft()
work.seed = 7

payload = cloudpickle.dumps(work)
received = cloudpickle.loads(payload)
run = received.config_finalize()

Cloudpickle transports executable Python objects. Never load a pickle from an untrusted source. Sender and receiver should use the same Python version and compatible nshconfig, Pydantic, and project dependencies.

Drafts retain their assigned values and interpolation callables. Unbound templates retain their inert constructor recipes and bind normally after restoration. Finals retain their concrete validated values. A final does not become a draft and cannot reconstruct the original composition recipe.

Config classes may use eager annotations, quoted forward references, or from __future__ import annotations. During by-value transport, each Config class defers reconstruction of its own Pydantic core validator and serializer until cloudpickle has restored the full dynamic class. This avoids partially materialized cyclic schemas without imposing a special annotation style.

Importing nshconfig does not install global pickle reducers for Pydantic core types. Unrelated Pydantic models keep their normal pickle behavior.

Cloudpickle is appropriate for trusted, short-lived executable transport. For durable run metadata, serialize the final’s concrete values using the application’s chosen format and versioning policy. nshconfig does not define a record envelope or stable content fingerprint.