Livewire 3 Upgrade Blocker Lint
Livewire 2 code does not fail loudly when you move to Livewire 3. It compiles, the page renders, and
then a button does nothing. $this->emit('saved') throws only when that method runs. wire:model.defer
parses as an unknown modifier and is ignored. wire:model.debounce.400ms stops sending requests at all
because debounce now only applies to .live bindings. livewire:load never fires, so the Alpine
component inside it never initialises. A <livewire:row> inside @foreach without :key keeps
rendering — it just hands row 3's state to row 4 after a delete.
This extension reads the file in front of you and names each of those lines with the Livewire 3
replacement next to it.
What it checks
15 rules over **/*.php (which includes .blade.php), in three groups:
- Events (4 rules, all errors):
$this->emit(), $this->emitTo(), $this->emitSelf() /
emitUp(), $this->dispatchBrowserEvent().
- Blade directives and modifiers (6 rules):
wire:model.defer, wire:model.lazy,
wire:model.debounce without .live, wire:click.prefetch, livewire:load, @livewireStyles.
- Component surface (5 rules):
protected $queryString, namespace App\Http\Livewire,
$wire.entangle(...).defer, assertEmitted / assertNotEmitted in tests, and a
<livewire:...> tag inside a loop with no :key.
Comment lines and {{-- --}} Blade comments are stripped before matching, so a migration note that
mentions emit() is not reported.
Measured on the shipped fixtures
_fixtures/dirty.php is a 43-line Livewire 2 component. Audited 2026-09-18 the engine reports
14 blockers — 10 errors and 4 warnings, covering 14 of the 15 rules (the 15th is a test-file
rule). _fixtures/clean.php is the same component rewritten for Livewire 3 and reports 0.
Both files ship inside the extension, so the numbers above are reproducible on your machine.
grep -r "emit(" finds the event calls. It does not find a <livewire:row> inside @foreach that is
missing :key, because that defect is the absence of an attribute inside a block — it needs the loop
depth, which a line-oriented search does not have. It also cannot tell wire:model.debounce (dead)
from wire:model.live.debounce (correct), since one is a prefix of the other.
Yardstick
A freelance Laravel developer at $85/hour spends the first hours of
an upgrade doing exactly this pass by hand across every component in the app.
Free and paid
Free, no key: scan the file you have open and get every blocker with its Livewire 3 replacement, line by
line. That finishes the file. Paid: scan every .php and .blade.php in the workspace in one command
and export a REPORT.md / JSON with file:line you keep, plus a non-zero exit code for CI.
$29 once - one licence key per person or team seat, 7-day full refund: https://buy.polar.sh/polar_cl_JoEBGmMxghz3XsayVbZSJktcNspzSxRkJYcdc3S0eYU
Also in the browser
The same engine — the same rules.json, the same check() — runs on one page with no install:
https://getreadystack.com/tools/livewire3-upgrade-blocker-lint
Scope
This extension reads Livewire 2 → 3 API changes. It does not run your app, does not rewrite files, and
sends nothing anywhere: matching happens locally, line by line.
