My Chrome extension has no server, so I put the paywall on a remote switch

I'm a solo dev with zero users right now, and I just spent an afternoon on a decision most people would've hardcoded in five minutes. Here's the setup. NotebookBloom is my Chrome extension for Google's NotebookLM. At launch I don't want to charge for much — I want people to actually use it, tell a friend, leave a review. So the plan is: only cloud sync (Google Drive backup) is Pro on day one. Everything else — flashcard export to Anki, citation export, bulk import — free. But "free on day one" implies "not free forever." Once there are enough users, I want to flip some of those to paid, one at a time, watching what happens. And that's where I hit a wall that only exists for extensions: there is no server runtime. My extension runs in the user's browser. So if I write "is this feature paid?" as a hardcoded if in my code, then flipping it later means: edit code → rebuild → upload to the Chrome Web Store → wait for review[你查到的审核时长，如 "usually under a day, sometimes 3"]. Think about that. A pricing change — arguably the most business-critical lever I have — would be stuck in a review queue. That's absurd. So I stopped and rebuilt it as a switch. One file, features.ts , with a single decision function: canUse(feature, isPro, gates) → isPro OR the feature isn't currently gated Four flippable keys: cloudSync, ankiExport, citationExport, bulkImport. The default (compiled into the extension) is: cloudSync = paid, the rest = free. That's my day-one tiering. The switch values live in my Cloudflare Worker's KV. To flip Anki export to paid, I change one KV value — no rebuild, no store review. Every user picks it up within a day. The part I'm quietly proud of: it costs zero extra requests. The extension already calls /status to check "does this Google account have a subscription?" (you can't trust the client to self-report that — that's how you get pirated). I just piggybacked the switch values onto that same response. The paywall config rides along on a request I was already maki