Summary

Two optional features have demonstrated strong stability through extensive live testing and should be added to the default feature set in root Cargo.toml.

Features to Promote

scheduler

• Current: optional, requires --features scheduler
• Code impact: 34 #[cfg(feature = "scheduler")] sites
• Dependencies added: zeph-scheduler (cron + sqlx) — cron, chrono, schemars are lightweight; schemars already non-optional in 7 other crates
• CI verification: Live verified across CI-30, CI-32, CI-54, CI-58. Zero open bugs. Natural-language scheduling, cron parsing, deferred tasks all working
• Config: scheduler.enabled = true is already the default in config/default.toml

guardrail

• Current: optional, requires --features guardrail
• Code impact: 48 #[cfg(feature = "guardrail")] sites
• Dependencies added: Zero — marker feature enabling code paths in existing crates
• CI verification: GuardrailFilter, DestructiveCommandVerifier, InjectionPatternVerifier all live verified
• Runtime default: disabled ([security.guardrail] enabled = false) — feature flag only controls compilation, runtime toggle controls behavior

Changes

1. Root Cargo.toml: default = ["bundled-skills", "scheduler", "guardrail"]
2. Remove scheduler from desktop and server bundles (now redundant with default)
3. Clean up empty scheduler = [] feature in crates/zeph-core/Cargo.toml
4. Update CLAUDE.md feature flag documentation

Risk

LOW. Adding features to default is additive. Users with default-features = false are unaffected. No behavioral change (scheduler config already defaults to enabled; guardrail runtime-disabled by default).

Analysis

Full details: .local/reports/feature-stabilization-analysis.md, Section 2