In this episode, we're building a blazing fast infinite scroll with Inertia.js, tackling it from scratch so you can see the whole process start to finish—including some refactoring and a few real-world gotchas that come up along the way.
We kick things off by demoing the infinite scrolling experience: new posts load smoothly as you scroll, and nothing happens when you hit the very bottom—just as it should. Then, we spin up a fresh Laravel Breeze project, set up models, migrations, factories, and a seeder to get a realistic batch of posts in the database—making sure post dates are incremented so they look like they were really published over time.
After getting the backend ready, we lay out the frontend with Inertia and Vue, styling our post list for scrollability. We use Vue's ecosystem to pull in the intersection observer composable, which makes detecting when we're at the bottom of the post list a piece of cake. As the observer fires, we load more posts.
First, we try handling new data with Inertia's built-in router, but we quickly run into an issue: state management gets messy, and URLs update in a way that's not ideal for infinite scroll (we don't want the page query parameter to update every time). To sort this, we switch from Inertia's router to plain old Axios requests for fetching more posts, keeping things decoupled from navigation.
But there's another bump: using classic pagination makes it awkward to know where we are in the list and inefficient for large datasets. So, we overhaul things again to use cursor pagination (much faster and more reliable for this use case). We show how to update your backend and front-end logic for cursor pagination, including how to update and append new posts, as well as update fetch pointers (the cursors) for each subsequent fetch.
To polish up the UX, we tweak the infinite scroll so new content preloads a bit before the absolute bottom of the page, using a CSS trick. That way, scrolling feels smoother, and posts are ready as the user arrives. Finally, we ensure that once all posts have loaded, our intersection observer stops firing, so you won’t end up looping through content endlessly at the bottom.
By the end, you’ll have a super fast, user-friendly infinite scroll in your Inertia-powered app. We cover best practices, gotchas, and give you tricks to make your implementation feel extra polished!