1:1 mentoring with Big Tech AI engineers
System Design

Deployment & Rollout

Deploy and roll out AI systems: canary releases, feature flags, A/B testing, and safe rollback strategies.

Last updated

SD-20

Deployment & Rollout Patterns for LLM Systems

Shadow traffic, gated canaries, judge-scored A/B tests, blue-green swaps, a versioned prompt registry, and rollback triggers that fire before users do — plus the postmortem every interview answer should reference: OpenAI’s April 2025 GPT-4o sycophancy rollback.

Deploying LLM systems differs fundamentally from traditional software deployment. Model behavior is non-deterministic, prompt changes can cascade unpredictably, and quality regressions are harder to detect than functional bugs. This section covers battle-tested patterns for safely rolling out model updates, prompt changes, and new AI features to production.

Shadow Mode Deployment

Shadow mode (also called "dark launching") runs a new model or prompt version alongside the production system without exposing results to users. All requests are dual-written: the production path serves the user, while the shadow path processes the same input asynchronously for comparison.

Shadow Mode Architecture

Related

More in System Design

Get full access to all 87+ sections with code examples, diagrams, and interactive animations.

Unlock Premium