Put a feature behind a flag

Ship a feature dark and turn it on per user, role, organization or everywhere, without a deploy.

1. Register the flag in src/server/flags.ts, and call the helper first in services/api/src/server.ts, in the feature-flags block:

   import { registerFlags } from "@monark/feature-flags/server";
   
   export function registerPostsFeatureFlags(): void {
     registerFlags("posts", {
       scheduling: { description: "Schedule posts to publish later.", defaultOn: false },
     });
   }
   

   New behaviour starts defaultOn: false. Use true only for a kill switch over something already shipped.
2. Check it on the server where the feature starts, in the caller's scope so overrides apply:

   const on = await isEnabled("posts.scheduling", { userId: ctx.userId, organizationId: org.id });
   if (!on) throw new ForbiddenError("Scheduling isn't enabled for this organization.");
   

   isEnabled comes from @monark/feature-flags/server, ForbiddenError from @monark/common.
3. In the web app, hide the entry point when the flag is off. A server component can read featureFlags.getAllForSession and call notFound(), as services/web/src/app/(authed)/wiki/layout.tsx does. A navigation entry takes a flag property in services/web/src/config/primary-nav.ts.
4. Turn it on locally: in tools/enable-dev-flags.ts, call your register helper next to the others and add the key to DEV_FLAGS, then run pnpm enable:dev-flags.

Good to know:

• The most specific override wins: user, then role, then organization, then global, then defaultOn.
• Hiding a button isn't protection. The server check in step 2 is the boundary.
• Never rename or reuse a shipped flag key.

Next: Change the database schema