Feature growth and boundaries SSOT (2026)

This document defines the authoritative boundaries for Vox feature growth to prevent “God Object” sprawl and crate bloat. It also documents the machine-verified gates that ensure language surface stability across the compiler, runtime, and app contract.

The Drift Gate (Projection Parity)

To ensure that the WebIR, AppContract, and RuntimeProjection do not drift, we enforce a deterministic projection mapping. Any changes to the core language surface that impact the target application projection must be reflected in the test suite.

The canonical gate is:

Test: projection_parity
Validation: projection_triplet_is_deterministic
Reproduction: cargo test -p vox-compiler --test projection_parity

Failure of this test indicates a non-deterministic or unmapped change to the HIR/IR transformation that breaks the AppContract stability guarantee.

Sprawl Limits

Maximum Workspace Crates: 40 (Audit April 2026 identified 63; remediation active).
Core Compiler LOC Limit: 50 kLOC.
Orchestrator Boundary: DEI daemon must remain protocol-agnostic.

Crate Modularization

Every new feature requiring a dependency with >10 downstream crates MUST be placed in its own workspace crate (e.g., vox-oratio for speech-to-code) to keep the core vox binary and vox-compiler library lean.

Governance

Changes to the feature set defined here require an ADR (Architectural Decision Record) and a corresponding update to the operations catalog.