bill-feature-guard

Enforce a single feature-flag guard for safe rollout and rollback.

13|1|Updated Mar 16, 2026
One-click install
npx skills add https://github.com/Sermilion/skill-bill --skill bill-feature-guard
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: bill-feature-guard
Source: https://github.com/Sermilion/skill-bill/tree/main/skills/bill-feature-guard
Command: npx skills add https://github.com/Sermilion/skill-bill --skill bill-feature-guard

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

Enable feature flag mode to guard code changes with flags for safe rollback and gradual rollout, ensuring predictable behavior during releases.

Core Features & Use Cases

  • Centralized single flag guard at the routing/entry point to switch between new and legacy paths.
  • Rollback guarantee: OFF means no behavioral changes; ON activates new logic with proper isolation.
  • Clear guidelines for naming, defaults, and documentation to prevent drift and maintain safety.
  • Supports varying change sizes: Small, Medium, Large with the Legacy pattern for large rewrites.

Quick Start

Define a feature flag, rename the existing implementation to Legacy, add a new path, and wire a single flag check at the router to switch between paths.

Frequently Asked Questions about bill-feature-guard

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I use feature flags for safe rollback and gradual rollout?

Use a centralized feature flag guard at the routing or entry point to switch between new and legacy paths, ensuring OFF means no behavioral changes while ON activates isolated new logic for safe rollback.

What is the Legacy pattern for large architectural rewrites?

The Legacy pattern renames the existing implementation to Legacy, adds a new path, and wires a single routing-level flag check to switch between paths, isolating large changes for predictable rollback.

How do I implement a single routing-level flag check for A/B testing?

Define a feature flag, rename the existing implementation to Legacy, add a new path, and wire a single flag check at the router to switch between paths, ensuring clear isolation and default off behavior.

Does feature flag rollout require specific naming conventions and documentation?

Yes, feature flag rollout requires clear naming conventions, default off behavior, a single routing-level flag check, and explicit documentation with validation steps to prevent drift and maintain safety.

Can I apply feature flag guardrails to small code toggles and large rewrites?

Yes, feature flag guardrails apply across development contexts from small toggles to large architectural changes, providing clear guidelines and checks for isolation, naming, and documentation.

When should I not use a feature flag for code changes?

Avoid using feature flags when you cannot guarantee isolation or enforce a single routing-level flag check, as multiple scattered checks break the rollback guarantee and create behavioral drift.