Modernizing legacy systems with the Strangler Fig pattern— Daniel Raniz Raneland

Stuck in a legacy system that needs modernizing? Feel like the best course of action is to throw it in a dumpster, light it on fire and rewrite everything from scratch - maybe even in a different language?

Hold that thought. While it may be tempting to start a rewrite, rewrites of complicated systems rarely succeed because of multiple reasons. Chief among them is time and the fact that not everything can stop and wait for the rewrite, but another important contributor is the second system effect, which usually causes rewrites to be of lesser quality than that which they replace.

In this talk I'll share my experiences with the Strangler Fig pattern, which is a better approach where the original system is gradually replaced by breaking out or rewriting parts into separate systems. I'll also talk about combining this with Domain Driven Design and how paying attention to the new design can also make sure that you align with Conway's law.

Outline of the session:

- Something about legacy systems
- Rewrites and issues with them
- The strangler fig pattern
- Testautomation
- DDD/Conway’s law
- Experiences
- Summary

ABOUT DANIEL

Daniel Raniz is a programmer, architect, speaker and coach at factor10. He is a problem solver who keeps track of the bigger picture. He is prestigeless, likes to get into new domains, and loves sharing knowledge and ideas. Raniz has worked with system- and software architecture at several companies since 2010 and has been with factor10 since 2021. When not working he's into beer brewing, sourdough bread, 3D printing and triathlons.

- LinkedIn: https://www.linkedin.com/in/raneland/
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- GitHub: https://github.com/raniz85
- Blog: https://raniz.blog