ConfigKit/docs/roadmap/deferred.md

Deferred Scope

This document owns intentionally excluded features, not a committed delivery plan. The future feature list preserves candidate enhancements and open questions without changing these exclusions. The architecture policy governs changes to these boundaries. Implemented behavior belongs in the configuration contract and consumer adoption in the consumer guide.

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 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.

Effective configuration diffs are implemented over frozen successful-load inspections; their current comparison and disclosure contract is in the configuration contract, with consumer workflows in the adoption guide. Fingerprints remain deferred.

Built-in sibling inheritance using extends is implemented as described in the configuration contract. It is distinct from inheritance between selected overlay files, which remains excluded above.

Possible source-version follow-ups

Independent collection or subtree specification policies were outside the completed shared source-version feature and remain possible future work, with no committed delivery plan. Current source-version checks use one application-owned policy across participating documents. Reconsider independent policies if concrete consumer needs justify a separate design decision; this is not a permanent prohibition. The original request and its selected scope remain at e4270c9:docs/roadmap/promptkit-feature-request.md in Git history. Existing sequence-composition and cross-scope inheritance deferrals above also remain unchanged.

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/.