Next.js 15 Is Here (Vercel Ship Breakdown)

for sell ship just happened from next 15 to firewalls to AI to GMA wearing a white shirt finally to shouting out Dax of all things and you all out there with no users yet this is a very interesting event not too much massive news but enough small things I think it's important to go through that here I am on my day off filming a quick video so I can go over this with you guys before I go any further though I want to be very very clear this video is not sponsored I'm not being paid to make this I work with forell and other content pretty regularly but this is my genuine thought

and beliefs about what happened here no money has been exchanged theyve not seen this video ahead of time they have no opportunity to approve or change anything I've said here this is just how I feel about this release with all that said let's dive in before we get to the juicy neck stuff which is let's be real the reason you should be here let's go over the quick two additional announcements first first is the forell firewall this is I'll be frank a little overdue most of the web just relies on cloud flare as their way of dealing with random dos style traffic and that's fine Cloud flare is totally fine for that but put Cloud flare as your CDN in front of

something like vercell has historically caused all sorts of weird caching issues that aren't Pleasant to solve and vercel should be the ones doing this nice to see that vercel is actually taking this problem seriously and giving us the ability to quickly set up rules to keep people from destroying your websites and making your bills go massive nice to have this finally in haven't tried it yet but it looks really good check out the blog post if you're curious the other fun thing they rethought feature Flags they actually shouted out Jane Wong when they brought this up which I thought was really cool because if you're familiar with Jane she loves leaking features and products by going

through their feature flags and finding things that probably shouldn't have been there so I worked at twitch I was always curious how they did feature Flags turns out once you don't work at twitch and you look at it it's actually kind of hilarious okay I knew this when I was there but seeing it outside is even funnier you load any page you see this huge settings thing load I just threw this in vs code so we take a better look at it there's a key in this called experiments experiments is every single feature flag on Twitch you'd think that these uyu IDs would off you skate it pretty well but they also put the name

of it these are the names that they use internally for all of these things so if you want to see any of these features like chat pause on Hover by default 100% of people are in the control group 0% are in the treatment group if you just manually swap these values around suddenly you're going to see this feature all of the features twitch is working on that are already shipped are probably in this file somewhere which is kind of hilarious because that's how almost every website that does feature Flags Works they're super insecure and hackers like Jane can go into these files go into these mobile apps and just

flip these values around and now they can see everything you're working on which kind of sucks this is why versell is building feature Flags more deeply into versell because that should be happening on the server not on the client as soon as you let the client do all of the feature flag work you have now allowed the client to see every single feature that might exist in your app if the server is not the thing generating the UI then the issue you're running into now is that every possible State the UI can be in has to be encoded in the binary the user has be it a mobile app or website Co didn't think this problem seriously haven't really used this too much I know my CTO has he

says it's really good so far excited to see them taking this stuff more seriously enough about versel though what we're here for is nextjs 15 to be clear it's an RC but to be clearer it's not an RC because it's not ready to ship it's an RC because they're blocked on something they're blocked on react 19 it's still an RC because they're waiting for react 19 to be the official release and not also an RC the moment react 19 ships I am positive next 15 will be the official release within a few hours if not minutes so let's take a look at the actual things that here cuz there's a

lot of fun stuff obviously if you want to play with us today you can just npm install next RC you can also use the new create next app RC to get all the fun new things they change and create next app still not as good as create T3 app by the way but good to look at regardless so react 19 the next CH app router is built on the react Canary channels for Frameworks you might not know that you might think oh but I put react 18 or 17 in my package Json fun thing about next is that at this point in time app router ignores what you put here and just loads what ever version of