The strangler-fig pattern, done right, lets you decompose a legacy system incrementally while it keeps serving real traffic.
Big-bang rewrites are where good products go to die. The safer path is incremental: route by route, service by service, you strangle the monolith until nothing is left.
The key is a routing layer that can send traffic to either the old or new implementation. Ship the new path behind a flag, compare outputs, then cut over when confidence is high.
Observability is your safety net. You can't modernize what you can't measure. Instrument everything before you change anything.
Enjoyed this?
Get our monthly engineering and AI insights, straight to your inbox.