In TypeScript, there are at least 4 ways to implement immutability. Here's how I choose between them.

Very well explained, Cory!

Question: At what point in the development cycle do you begin to worry about immutability? For solo or very small teams focused on deploying asap should this be a priority?

Fully-typed and fully-tested deepFreeze:

we need a 5th way

I’m likely forgetting at least two

@ezdubs_bot english to japanese

Only in JavaScript, we declare something as const but then add an `as const` at the end of it to say, please remain immutable.

So how would you choose between the typescript versions? Mainly when to use `as const` vs `readonly/ReadOnly`

readonly is the only granular option. Otherwise I generally prefer “as const”

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