Next.js App Router in Production: Lessons from 150K+ Users

OpenMyPro has served 150K+ users on Next.js App Router since we migrated from the Pages Router. The migration was worth it, but it came with lessons that no documentation prepared me for. Here are the real production insights from running App Router at scale in a healthcare marketplace.

The Migration Decision

We started OpenMyPro on Next.js Pages Router because that was the stable option when we launched. When App Router reached stability, we migrated because Server Components offered significant performance benefits for our use case. Healthcare provider pages are data-heavy — specialty information, availability calendars, reviews, pricing — and Server Components let us fetch and render all of this on the server without shipping the data-fetching logic to the client.