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featuresJune 29, 2026· 5 min read

Prompt versioning and A/B testing (CPROMPT): how it works and when to use it

Prompt versioning and A/B testing (CPROMPT), versions prompts on every write, renders variables, and runs sticky per-user A/B splits, so you roll back or test without a code deploy. Here's how Crowkis does it and why it matters for cost and safety.

Production LLM traffic is deeply repetitive, and repetition is exactly what a bill is made of. Prompt versioning and A/B testing (CPROMPT) is how Crowkis versions prompts on every write, renders variables, and runs sticky per-user A/B splits, so you roll back or test without a code deploy.

In plain words: In plain words: prompt versioning and a/b testing (cprompt) versions prompts on every write, renders variables, and runs sticky per-user A/B splits, so you roll back or test without a code deploy.

How it works

Crowkis versions prompts on every write, renders variables, and runs sticky per-user A/B splits, so you roll back or test without a code deploy. It runs inside one Redis-compatible engine, so it composes with semantic caching, agent memory, and the other intelligence layers instead of being a separate service you wire together.

crowkis cli
CPROMPT SET support "You are concise. Answer: {{q}}"

Why it matters

Repetitive LLM workloads are where the money is, and semantic caching can cut costs up to 60-70% on repetitive workloads. Prompt versioning and A/B testing (CPROMPT) is part of what makes that reuse safe rather than reckless, the difference between a cache you trust in production and one you audit after every incident. Community edition ships at full power, free to run.

Infrastructure earns the critical path one boring, verifiable feature at a time.