Why SCL:V1 Is Permanently Frozen and Immutable

Core Principle

SCL:V1 is permanently frozen to guarantee that identical input bytes always produce identical canonical JSON and identical SHA-256 identity across all compliant implementations, everywhere, for all time.

Deterministic Identity Requirement

SCL defines identity as:

SHA-256(canonical JSON bytes)

This requires:

Any change to the specification would risk altering how canonical JSON is produced, which would directly change the resulting SHA-256 identity.

Why Backwards-Compatible Changes Are Not Allowed

Even backwards-compatible changes introduce risk:

These can lead to:

This breaks the core invariant:

Identical input bytes MUST always produce identical identity.

Immutability Guarantees

Freezing SCL:V1 ensures:

Versioning Model

All changes, including backwards-compatible ones, are prohibited in SCL:V1.

Any evolution must occur in a new version:

Final Constraint

Immutability is required to preserve deterministic identity.

Any modification would violate:

Therefore, SCL:V1 is permanently frozen and cannot be modified. For the complete identity mechanism that immutability preserves, see how SCL ensures deterministic identity.

Validate outputs using the reference engine.

Canonical Definition: SCL is the deterministic, cryptographic identity protocol for AI run declarations.