Janus Ascent

Janus is the semantic ascent path for Harness. It does not own authority in v0.

Promotion stages:

experimental
shadow
candidate
default
authoritative

v1 Janus modules are pure validators and evaluators:

• policy decisions
• event schema validation
• extension manifest parsing
• evidence invariants
• skill resolution
• deterministic workflow nodes

v2 Janus modules may run as supervised sidecars over stdio or a local socket. Kratos still owns timeouts, resource limits, input validation, output validation, policy finalization, fallback, and audit records.

v3 kernel candidacy requires passing conformance tests, stable ABI boundaries, deterministic serialization, fuzz-tested parsers, crash discipline, and hostile input hardening.

The rule is conformance before authority.