En bref, MobX is unopinionated util lib , while MST is an opinionated solution built on top of MobX. If you’re new to MobX, just use MST.
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MobX does not provide any restrictions on how new states can be derived from old ones . It’s more of a Data flow library as its creator likes to call it. MobX helps us set up Reactivity outside React components. This way view components can be kept free of logic.
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