Sidecar Pattern
ELI5 — The Vibe Check
The sidecar pattern attaches a helper container to your main app, like a motorcycle sidecar. The sidecar handles cross-cutting concerns — logging, monitoring, TLS — so your app can focus on business logic. It's the loyal sidekick that handles the boring stuff.
Real Talk
A deployment pattern where a secondary container (sidecar) runs alongside the primary application container in the same pod/host, providing supplementary functionality. Sidecars handle cross-cutting concerns like logging, monitoring, service mesh proxies (Envoy/Istio), configuration, or security without modifying the application code.
When You'll Hear This
"We attach a sidecar proxy for mTLS so the application doesn't need to handle encryption." / "Istio injects an Envoy sidecar into every pod to handle service mesh networking."
Related Terms
Ambassador Pattern
The ambassador pattern puts a proxy between your app and the outside world that handles all the annoying connection stuff — retries, circuit breaking, rout...
Kubernetes
Kubernetes is a robot manager for your containers.
Service Mesh
In a microservices system, every service needs to handle retries, timeouts, mutual TLS, and send traces. You could code all that in every service.