Before considering your migration complete, verify these items.
✅ Code Changes
- All
let x = value→let x = $state(value) - All
$: derived = ...→let derived = $derived(...) - All
$: { sideEffect }→$effect(() => { ... }) - All
export let→let { ... } = $props() - All
on:event→onevent - All
<slot />→{@render children()} - All
createEventDispatcher→ callback props - All
$$props/$$restProps→ destructured$props()
✅ Imports Cleaned
- Removed unused
onMount,onDestroy - Removed
beforeUpdate,afterUpdate - Removed
createEventDispatcher - Evaluated store usage (keep or convert)
✅ Testing
- All unit tests pass
- All integration tests pass
- All E2E tests pass
- Manual QA complete
- No console warnings about mixed mode
✅ TypeScript (if applicable)
- Props have proper types
- State has proper types
- No
anytypes introduced - Build passes with strict mode
✅ Performance
- No unnecessary effects
- Derived values used for expensive calculations
- Effect cleanup in place
- No memory leaks in dev tools
✅ Documentation
- README updated if needed
- Component docs updated
- Breaking changes documented for library consumers
Final Steps
bash# Clean build rm -rf .svelte-kit node_modules/.vite npm install npm run build # Run full test suite npm run test # Check for any warnings npm run dev 2>&1 | grep -i warn
🎉 Congratulations on completing your Svelte 5 migration!