Shopify Winter '26 — The Renaissance Edition — is the release where natural language stopped being a marketing promise and became a real operational layer inside the admin. Sidekick now edits themes through conversation, builds custom apps from prompts, and wires up Flow automations on command. For solo operators, it removes a genuine bottleneck. For production work, a developer still wins. Here's what actually shipped, what the real limits are, and how to start using it this week.