I Built a Free Laravel Package That Catches Slow Queries and Writes the Migration For You

wilfridterry — Sat, 13 Jun 2026 12:41:01 +0000

Your production database is slow. You know it. Your users know it. But you don't know when it started or which deploy broke it.

Yesterday's deploy made some query 4x slower. Telescope shows "current state" — but not the regression. Pulse tells you "queries are slow" — but not what changed. You're left digging through git logs and running EXPLAIN manually.

I built Cardinal to answer one question: "Which deploy made which query slow?"

The Problem

Let's say you deploy at 3pm. By 6pm, your error tracking shows increased timeout exceptions. You check Telescope — queries look fine now. You check git history — 47 commits since 3pm. You run EXPLAIN on 10 queries manually. Stress.

This is the "production detective work" pattern. Every team does it. Most solve it by:

Keeping spreadsheets of "known slow queries"
Setting up separate query monitoring (expensive SaaS, usually APM)
Running slower:analyze locally in dev (misses production patterns)
Doing nothing and accepting slow deploys

Cardinal does the detective work for you.

What It Does

Install the free Laravel package:

composer require cardinal/laravel

That's it. No setup. It hooks into your database automatically.

It Catches Three Things

1. Slow queries — tracks every query, alerts when p95 crosses your threshold (default 500ms).

2. N+1 queries — detects when the same fingerprinted query repeats inside a single request.

Warning: N+1: SELECT * FROM products WHERE id = ? [150 repeats in single request]
Location: app/Http/Controllers/OrderController.php:42

3. Missing indexes — parses WHERE and JOIN conditions, checks your schema, suggests an index if a leading column is uncovered.

The AI Part

Run php artisan cardinal:analyze {id} and Cardinal:

Gets the query template and its EXPLAIN output
Reads your table schema (columns, indexes, constraints)
Sends context to Claude or OpenAI (your API key, your cost)
Returns a structured diagnosis + ready-to-run migration

$ php artisan cardinal:analyze slow-query-123

Diagnosis:
  Query was doing a full table scan of 2.1M rows.
  Missing composite index on (user_id, status).

Fix migration generated:
  php artisan cardinal:fix slow-query-123

Expected improvement:
  p95 latency: 1200ms to 120ms (~10x faster)

Real Example

// OrderController.php
$orders = Order::with('items')->get();

foreach ($orders as $order) {
    $order->customer->name; // triggers N+1
}

Cardinal catches this automatically:

N+1 Detected
Query:    SELECT * FROM customers WHERE id = ?
Repeats:  247 times in single request
Location: app/Http/Controllers/OrderController.php:18

Fix: Order::with('items', 'customer')->get();

How It Works

Hooks into DB::listen — zero changes to your code
Fingerprints each query (strips all literals, normalizes whitespace)
Buffers per-request in memory — no DB write on every query
Detects patterns in terminating() hook
Stores only issues and aggregates, never raw query values

Overhead: listener adds less than 0.05ms per query in recording mode. EXPLAIN and schema inspection run only on-demand via artisan commands, never automatically in production.

Privacy

The fingerprinter strips all literals before anything is stored or sent. This is verified by a dedicated CI test that asserts no raw values pass through. Only normalized templates like select * from orders where user_id = ? are ever stored.

Installation

composer require cardinal/laravel
php artisan migrate
php artisan cardinal:report

Supports Laravel 10, 11, 12, 13 and PHP 8.2+.

Why Free?

The free package is complete and useful forever. You get continuous monitoring, AI analysis with your own key, and generated migrations. No account required.

Cardinal Cloud (paid, waitlist open) will add production history, deploy-to-regression tracking, and team alerts — starting at $19/month.

GitHub: https://github.com/wilfridterry/cardinal
Packagist: https://packagist.org/packages/cardinal/laravel

Open an issue if something doesn't work. Feedback directly shapes what gets built next.

laravel #php #database #performance #opensource

DEV Community: wilfridterry