Avoid Using Effects To Derive Values In Svelte

Learn how Svelte 5 reactivity works and when to derive values using `$derived` by learning how signals work under the hood.

🔖 Timestamps

0:00 Intro
0:35 Ad
0:51 How Does Svelte Reactivity Work?
4:27 Using The Derived Rune
10:39 Don't Use Effects To Update State
14:36 You Don't Have To Use $derived
17:57 How Do Signals Work?
21:17 Updating State With Functions And Writable Deriveds
25:15 Using Proxied State To Update Values
31:06 Don't Use $derived For Side-Effects
37:04 Outro

#joyofcode #sveltekit #svelte

[RonnieDenzel]

Best ad I ever seen, backed by a great explanation in svelte runes💯

[mikejohneviota]

Svelte 5 is almost there i feel it!!!!;🎉🎉🎉

[IsaacHarrisHolt]

Excellent video! I've been keeping an eye on your tweets and its good to see them with a nice explanation. Super helpful for someone who hasn't been able to explore Svelte 5 much! Also liked the more casual style for this one :)

[kavirajar]

As someone who's using svelte 5 in production this has been insanely helpful and relatable haha

[webstuffzak]

I love how much fun you're having. It's infectious.

[michaelm]

5:00 I know this is your catch phrase, but I absolutely love that this actually got me to laugh. Donating now.

[thedelanyo]

$effect for side effects. $derived for sync ✍️✔️

[muhammedhalilovic]

That's how easy peasy lemon squezy this is! Please don't call the police XD

Love your work man, keep it up.

[yash]

Aye, yo make more videos love your content

[ThiagoLagden]

My gov!!!
I don't know how I'm going to migrate my workarounds (hacker thing) 😁!!
Will you make a video about $bindable?

[alwayzsmarter]

I live in the us and don't think I could've spelled Fahrenheit off the cuff that quick

[vexkiddy]

how are you getting the IDE auto complete ? I'm using Webstorm and it still doesn't know what runes are :(

[cotyhamilton]

[object Object] how beautiful is that friends 😂

We had d (deez nuts 🤭) 😂

Had me cracking up today

[erickmoya]

Bro playing as overengineer Typescript functional developers "Oh I am using this and that then this that calls that, I am so smart"

[justingolden]

Reporting you to the Svelte police... for being too good, educational, and fun

[TheVertical]

I still dont see how Svelte 5 is easier than Svelte 4. While i love some of the new features, in general i have the feeling that this isn't what svelte was to me anymore. I could just use Vue3 if i want this.

[narrei]

sooo, if u r gonna just write normal code, you don't ever need to watch this video.
the problem is nobody is gonna write normal code so better watch to be aware of what you could cause.

[phoneywheeze]

it went from being jQuery like to react like

[yoanestradablanco]

I'm increasingly disillusioned with this Svelte project