Reactive blocks only run once per tick, preventing dependency re-runs
7/10 HighSvelte's reactive blocks have a limitation where they only run once per tick. If a dependency changes after a block has already run in that tick, the block won't run again, which breaks expected behavior and creates unintuitive side effects for use cases like transitions.
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Query: “What are the most common pain points with Svelte for developers in 2025?”4/5/2026
reactive blocks are only allowed to run once per tick; if a dependency changes after a block has run, too bad, the block won't run again. That is really shocking to me... A couple years ago, that feature used to work similar as useEffect, so I got used to use it for transitions, and now is biting my ass because the Svelte team are breaking my transition use-cases
Created: 4/5/2026Updated: 4/5/2026