strangler-fig

Migrate legacy monolith capabilities to a new architecture via a facade.

Updated Jun 5, 2026

Search Tags:#microservices #monolith #continuous delivery #risk mitigation #incremental migration

Ready to run

npx skills add https://github.com/hung-phan/system-skills --skill strangler-fig-hung-phan

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: strangler-fig
Source: https://github.com/hung-phan/system-skills/tree/main/skills/system-review/references/architecture-patterns/strangler-fig
Command: npx skills add https://github.com/hung-phan/system-skills --skill strangler-fig-hung-phan

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes scripts (resource) and references (resource) components.

What problem does it solve?

This Skill helps organizations replace legacy monoliths with modern architectures, reducing risk and ensuring continuous delivery without downtime.

Core Features & Use Cases

Incremental Replacement: Gradually replace a monolithic system by routing new behavior through a facade and migrating one capability at a time.
Minimal Risk: At every point in the migration, the system is in a working, releasable state, allowing for safe rollbacks if needed.
No Downtime: Enables continuous delivery during the migration process, with no need for maintenance windows or feature freezes.
Use Case: Ideal for systems that are too risky or complex for a big-bang rewrite, where capabilities are reasonably decomposable, and a routing layer can be introduced without significant latency.

Quick Start

Migrate a capability from a legacy monolith using the Strangler Fig pattern.

Frequently Asked Questions about strangler-fig

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

FAQPage Schema

How do I migrate from a monolith to microservices without downtime?▼

Migrate from a monolith to microservices without downtime by using the Strangler Fig pattern to incrementally route new behavior through a facade, moving one capability at a time while keeping the legacy system running. This ensures continuous delivery and safe rollbacks.

What is the Strangler Fig pattern and how does it work for legacy migration?▼

The Strangler Fig pattern is an incremental migration strategy that gradually replaces a legacy monolith by intercepting requests through a routing facade. It routes new capabilities to a modern architecture while delegating remaining functionality to the legacy system until migration is complete.

When should I choose incremental migration over a big-bang rewrite?▼

Choose incremental migration over a big-bang rewrite when your legacy monolith is too risky or complex to replace at once. If system capabilities are reasonably decomposable and a routing layer can be introduced without significant latency, gradual replacement minimizes risk.

Can I roll back a microservices migration if a new capability fails?▼

Yes, you can roll back a microservices migration safely because the Strangler Fig pattern maintains a working, releasable system at every step. The routing facade allows you to revert traffic back to the legacy monolith if a newly migrated capability encounters issues.

What are the limitations of using a facade for monolith decomposition?▼

The primary limitation of using a facade for monolith decomposition is that your system capabilities must be reasonably decomposable. Additionally, introducing a routing layer must not add significant latency to request paths, which can constrain highly coupled legacy systems.