# Deferred Scope

This document owns intentionally excluded features, not a committed delivery plan.
The [architecture policy](../policy/architecture.md) governs changes to these
boundaries. Implemented behavior belongs in the [configuration contract](../config.md)
and consumer adoption in the [consumer guide](../consumers/README.md).

## Explicit non-goals and deferred scope

General environment-variable configuration overlays are not supported. Typed secret
references and explicit directory bootstrap are the environment convention. Literal
credential configuration and implicit secret-directory discovery are unsupported.

The following remain deliberately excluded:

- automatic `conf.d` discovery;
- remote imports, arbitrary providers, and additional configuration formats;
- custom merge strategies, sequence merging, reset operators, multiple-parent
  inheritance, and cross-scope references;
- named overlay inheritance;
- parser-specific or custom structural-decoding extension APIs;
- generic dynamic-subtree conversion and module-registry APIs;
- automatic schema migrations;
- hot reload, runtime resource replacement, and remote resource validation;
- a bundled CLI framework or application commands; and
- configuration diffs and fingerprints.

Applications may build their own validate, effective-value, source, bootstrap, and
explanation commands around the library. Broadening these boundaries requires
concrete consumer evidence, compatibility review, and an explicit design change.

Built-in sibling inheritance using `extends` is implemented as described in the
[configuration contract](../config.md#sibling-inheritance). It is distinct from
inheritance between selected overlay files, which remains excluded above.

## Deferred performance experiments

The completed performance audit left these internal optimization candidates for
separate investigation:

- branch-local explanation replay instead of the current whole-tree replay;
- redesigning the private metadata-copy handoff while preserving detached public
  records;
- caching schema descriptors across loads; and
- indexing complex contributor-trace membership while preserving its equality
  rules and compact linked traces.

These are not committed implementation work. Reconsider them with evidence that
the benefit justifies the ownership, retained-memory, or equivalence risks. The
completed audit and implementation evidence are preserved in Git history at
`8e91a2b` under `docs/roadmap/`.