Repository boundary¶

Status: Active. Recorded 2026-10-05.

This record states what the scpn-quantum-control repository contains, what it does not contain, how the boundary is checked, and what the record does not claim. The reasoning behind the module structure inside the package is in Architecture Decisions.

Context¶

The repository grew from one Python package into a workbench: the package, two distributions with their own package metadata, a web portal, the tools and tests that gate all of them, and the committed evidence that the documentation cites. A plan exists to split the package into focused repositories. Until a split is reviewed and released, contributors and readers need one answer to "does this belong here, and who owns it?".

Decision¶

Everything stays in this one repository until a split is released. Ownership is recorded as data, not as convention:

data/split_preparation/split_domain_map.json assigns every unit of the package to a domain and every domain to one planned destination. A unit whose files belong to different destinations lists each file. Each classification that needed a decision carries the reason and the decision.
Every tracked path outside the package has an owner by path rule in the same file. Tools, workflows, data, documentation, notebooks and examples belong to the workbench itself.
The dependency direction between destinations is a declared graph. Imports that cross it against the direction are listed, one row per exception, in data/split_preparation/boundary_baseline.json. The list can shrink; a new or widened exception fails the check.

What the repository contains¶

Path	Content	Owner in the map
`src/scpn_quantum_control/`	The Python package	By unit, to the planned package destinations
`src/scpn/`	Compatibility import path for the differentiation interface	Workbench
`oscillatools/`	Coupled-phase-oscillator toolkit with its own package metadata	Sibling distribution
`scpn_quantum_engine/`, `src/scpn_quantum_engine.pyi`	Rust engine and its type stubs	Sibling distribution
`studio-web/`	Web portal	Studio destination
`tools/`, `tests/`, `.github/`	Gates, their tests and the hosted workflows	Workbench; tests follow what they import
`data/`, `results/`, `figures/`	Committed evidence and its digests	Workbench
`docs/`, `paper/`, `notebooks/`, `examples/`, `benchmarks/`	Documentation and worked material	Workbench
`experimental_workers/`	Isolated experimental worker	Workbench

What the repository does not contain¶

The classical SCPN engines sc-neurocore and scpn-fusion-core. The package talks to them through adapters; their code lives in their own repositories.
The Studio platform package scpn-studio-platform. The Studio lane installs it from a hash-locked requirements file.
Provider credentials, account identifiers and queue tokens. Hardware access is configured outside the repository.
A permissively licensed core. All code here is AGPL-3.0-or-later with a commercial licence route; see Core Package Boundary.
Any of the planned split repositories. None exists yet.

Risks accepted¶

One repository, one long gate. A full hosted run takes more than an hour (measured 2026-10-04). A change in one domain waits for the gates of all.
Existing exceptions are debt. On 2026-10-05 the guard reported 174 exception rows covering 292 import occurrences; its output gives the current figures. They are frozen, not solved.
Sibling distributions share the history. oscillatools and the Rust engine carry their own versions but are built and published by this repository's workflows, from this repository's commits.
Evidence is bound to sources by digest. Several committed evidence files record the digests of source and documentation files; changing such a file requires refreshing the evidence in the same change.

Commands¶

# Who owns every tracked path, and how the units depend on each other
python tools/audit_split_ownership.py --out /tmp/split-ownership

# No new, widened or stale exception to the declared dependency graph
python tools/split_boundary_guard.py

# Every tracked source kind is under a named gate
python tools/audit_source_surface_inventory.py

The hosted step "Validate split dependency contracts" runs the guard and the tests of the ownership tools on every push.

Non-claims¶

No split has been carried out. The destination names in the map are planned targets; they are not existing repositories, packages or teams.
The map records architectural responsibility. It is not a list of maintainers and grants no review rights.
No file is relicensed or dual-licensed by this record.
The exception baseline does not show that the remaining cross-destination imports are acceptable, only that their number cannot grow unnoticed.