GAMMA in Action: How Careem Migrated To Istio Without Downtime

11 November 2025 | KubeCon, Atlanta Georgia

https://sched.co/27FX9

Recording

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Abstract

Careem, the leading multi-service app in the Middle East, handles over 5 billion Kubernetes-based service requests daily. As our platform evolved, we began to outgrow the operational and extensibility constraints of our existing service mesh.

This talk shares how we executed an in-place, zero-downtime migration to Istio within the same Kubernetes cluster—without increasing infrastructure cost or rewriting most service configurations. A key enabler was our early adoption of the Kubernetes Gateway API (GAMMA initiative). By building on vendor-neutral, Kubernetes-native APIs for routing and traffic policies, we achieved a “define once, swap many times” model that allowed us to reuse the majority of our existing config during the transition.

To validate changes in production safely, we integrated Flagger to implement metrics-driven canary rollouts and gradual traffic shifting.

Slides

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Demo Code

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Reviews

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