arch-strangler-fig
Installation
SKILL.md
One-line summary
Wrap the legacy system in a facade. Route new functionality and gradually-rewritten existing functionality to new services behind that facade. When all functionality has migrated, the legacy system has been "strangled" and can be retired.
When to use this skill
- Migrating a monolith to microservices over months or years.
- Replacing a legacy system that's too critical to take offline for a rewrite.
- Decomposing a system whose internals are poorly understood — you migrate one behaviour at a time and rebuild understanding as you go.
- Any time someone proposes a "big bang rewrite". This is the safer alternative.
When NOT to use this skill
- The legacy system is small enough that a direct rewrite is genuinely shorter and lower risk.
- Functionality is so tangled that no clean facade can be drawn — first invest in a refactor that exposes seams.
- Strangulation is being used as cover for an indefinite migration that nobody intends to finish — the legacy never goes away.