CodeIgniter 4 Backend Development with JWT and Caching

When hosting resources are limited and you need to launch a project quickly, choosing a PHP framework often comes down to balancing performance and functionality. We've encountered situations where Laravel proved excessive—30–50 MB at startup, slow compilation, and high memory demand. For such cases, we use CodeIgniter 4: lightweight, no magic, with straightforward documentation. According to CodeIgniter's official documentation, the framework is designed for optimal performance on low-cost hosting. A typical project starts at $2,500, with savings up to 40% on server costs compared to heavier frameworks.

CodeIgniter 4 is a framework that doesn't get in the way of writing fast code. It provides a built-in ORM (Query Builder + Model), HTTP layer via PSR-7, JWT authentication out of the box, while consuming minimal resources. Ideal scenarios for CI4: small to medium websites, budget web servers, teams experienced with this framework, and projects with strict response time requirements on weak hardware. Learn more about the language's capabilities in the PHP documentation.

Starting Point for Backend Development on PHP (CodeIgniter)

The first step is always an audit of the current infrastructure and requirements. We analyze load, data volume, and expected growth. Then we design the database architecture and API, choosing optimal caching tools. CI4 allows quick scaffolding via its built-in code generator and migrations.

Common Problems Solved in CodeIgniter Backends

N+1 Queries and Inefficient Database Operations

A typical scenario: in a product list, an additional query is made for each category in a loop. In CodeIgniter 4, we use repositories or custom model methods with JOIN. For example, the getWithCategory() method pulls related data in one query. Instead of calling $product->category() for each product in a loop, we do one JOIN query: $this->db->join('categories', 'categories.id = products.category_id'). This reduces queries from N+1 to 1.

Lack of Structure in API

Many start writing logic directly in controllers. We apply a service layer and repositories. The controller only accepts requests and returns responses; all business logic is in services. This simplifies testing and maintenance.

Authentication and Authorization

We implement a JWT filter with role checking. The filter checks the token in the Authorization header, decodes JWT, and stores the payload in $request->user. Admin routes are protected with separate filters. This JWT authentication for CodeIgniter backend is both fast and secure.

How Does CodeIgniter 4 Perform on Shared Hosting?

On low-cost hosting, CodeIgniter 4 processes requests 2–3 times faster than Laravel under equal conditions. This is achieved through its streamlined architecture: fewer loaded classes, no facade magic, a simplified service container. For high-traffic sites, this yields up to 40% improvement in TTFB, which can translate to significant hosting cost savings.

Configuring CodeIgniter 4: Step-by-Step Guide

1. Install the framework via Composer: composer create-project codeigniter4/appstarter project-root.
2. Configure database connection in .env: database.default.hostname = localhost, etc.
3. Create migrations for tables via php spark make:migration.
4. Implement models with validation and relationships.
5. Write controllers and routes, connect the JWT filter.

Implementing JWT Authentication in CI4

namespace App\Filters;

use CodeIgniter\Filters\FilterInterface;
use CodeIgniter\HTTP\RequestInterface;
use CodeIgniter\HTTP\ResponseInterface;
use Firebase\JWT\JWT;
use Firebase\JWT\Key;

class JwtFilter implements FilterInterface
{
    public function before(RequestInterface $request, $arguments = null)
    {
        $authHeader = $request->getHeaderLine('Authorization');
        if (!str_starts_with($authHeader, 'Bearer ')) {
            return service('response')->setStatusCode(401)->setJSON(['error' => 'Unauthorized']);
        }

        try {
            $token = substr($authHeader, 7);
            $payload = JWT::decode($token, new Key(getenv('JWT_SECRET'), 'HS256'));

            // Check role if provided in arguments
            if ($arguments && !in_array($payload->role, $arguments)) {
                return service('response')->setStatusCode(403)->setJSON(['error' => 'Forbidden']);
            }

            // Store in request for controllers
            $request->user = $payload;
        } catch (\Exception $e) {
            return service('response')->setStatusCode(401)->setJSON(['error' => 'Invalid token']);
        }
    }

    public function after(RequestInterface $request, ResponseInterface $response, $arguments = null) {}
}

Stack and Configuration Example

We use the latest CodeIgniter version on modern PHP, PostgreSQL or MySQL, Redis for caching, Nginx. Frontend—Vue.js or React via API. Here's an example routing structure and controller.

// app/Config/Routes.php
$routes->group('api/v1', ['namespace' => 'App\Controllers\Api\V1'], function ($routes) {
    // Auth (public)
    $routes->post('auth/login', 'AuthController::login');
    $routes->post('auth/refresh', 'AuthController::refresh');

    // Protected via filter
    $routes->group('', ['filter' => 'jwt'], function ($routes) {
        $routes->get('profile', 'UserController::profile');
        $routes->resource('products', ['controller' => 'ProductController']);
        // Generates: GET /, GET /:id, POST /, PUT /:id, DELETE /:id
    });

    // Admin-only
    $routes->group('admin', ['filter' => 'jwt:admin'], function ($routes) {
        $routes->resource('users', ['controller' => 'Admin\UserController']);
    });
});

namespace App\Controllers\Api\V1;

use App\Controllers\BaseController;
use App\Models\ProductModel;
use CodeIgniter\HTTP\ResponseInterface;

class ProductController extends BaseController
{
    private ProductModel $productModel;

    public function __construct()
    {
        $this->productModel = new ProductModel();
    }

    public function index(): ResponseInterface
    {
        $page  = (int) ($this->request->getGet('page') ?? 1);
        $limit = min((int) ($this->request->getGet('limit') ?? 20), 100);

        $query = $this->productModel
            ->where('is_active', 1)
            ->orderBy('created_at', 'DESC');

        if ($categoryId = $this->request->getGet('category_id')) {
            $query->where('category_id', (int) $categoryId);
        }

        $total    = $query->countAllResults(false);
        $products = $query->paginate($limit, 'default', $page);

        return $this->response->setJSON([
            'data'       => $products,
            'pagination' => [
                'page'  => $page,
                'limit' => $limit,
                'total' => $total,
                'pages' => (int) ceil($total / $limit),
            ],
        ]);
    }

    public function create(): ResponseInterface
    {
        $data = $this->request->getJSON(true);

        if (!$this->validate($this->productModel->getValidationRules())) {
            return $this->response->setStatusCode(422)->setJSON([
                'errors' => $this->validator->getErrors(),
            ]);
        }

        $id = $this->productModel->insert($data);
        $product = $this->productModel->find($id);

        return $this->response->setStatusCode(201)->setJSON($product);
    }
}

Model with validation and custom methods:

namespace App\Models;

use CodeIgniter\Model;

class ProductModel extends Model
{
    protected $table      = 'products';
    protected $primaryKey = 'id';
    protected $returnType = 'array';
    protected $useSoftDeletes = true;
    protected $useTimestamps  = true;

    protected $allowedFields = ['name', 'slug', 'price', 'category_id', 'description', 'is_active', 'attributes'];

    protected $validationRules = [
        'name'        => 'required|min_length[2]|max_length[255]',
        'price'       => 'required|decimal|greater_than[0]',
        'category_id' => 'permit_empty|integer|is_not_unique[categories.id]',
    ];

    protected $validationMessages = [
        'name'  => ['required' => 'Name is required'],
        'price' => ['greater_than' => 'Price must be greater than zero'],
    ];

    protected $beforeInsert = ['generateSlug'];
    protected $beforeUpdate = ['generateSlug'];

    protected function generateSlug(array $data): array
    {
        if (isset($data['data']['name']) && empty($data['data']['slug'])) {
            $data['data']['slug'] = url_title($data['data']['name'], '-', true);
        }
        return $data;
    }
}

Estimated Timelines and What's Included

Small or medium site: 3–7 weeks. Timelines depend on API complexity and integrations. Typical project cost: starting from $2,500 (includes configuration, API, auth, caching). We'll estimate your project in 1 day—just contact us.

What We Do:

• Design database architecture and create migrations
• Implement REST API with JWT authentication
• Configure caching (Redis/File) and optimize queries
• Write unit and integration tests
• Prepare API documentation (Swagger/Postman)
• Deploy the project on server (Docker or bare-metal)
• Hand over access and train your team
• Provide 30-day warranty support

With over 8 years of PHP development and 20+ projects on CodeIgniter 4—from simple landing pages to marketplaces—we deliver 98% of projects on time. Get a fast, reliable backend without overpaying by contacting us for a consultation today.

Backend Development Services: Laravel, Node.js, Go, Django, PostgreSQL

On a production server at 3:14 AM, the Laravel Jobs queue stopped processing. 40,000 unprocessed jobs in Redis. Cause: worker crashed due to a memory leak in one of the Jobs (leak via a static variable in an Eloquent observer), supervisor didn't restart it because of misconfigured stopwaitsecs. This is not a hypothetical scenario — it's Tuesday. We analyzed such an incident on a project with 500 RPS load: diagnosis took 4 hours, fix — 20 minutes. So you don't lose money on downtime, we offer backend development services with a focus on production-grade reliability. We'll assess your project in 2 days.

Backend is what works when no one is watching. Or doesn't work. We guarantee you'll have the first option.

How do we ensure production-grade reliability from day one?

What we do correctly from day one

Service Layer over Fat Controllers. Controller receives HTTP request, validates it via Form Request, passes data to Service, returns response. Business logic in Service, not Controller. This sounds trivial, but most legacy projects have controllers with 500 lines and SQL queries inside.

Repository Pattern we use cautiously. If you just wrap Model::where(...) in a repository method — that's boilerplate without benefit. Repository is justified when: you need to abstract from the data source (DB + cache + external API) or when query logic is complex enough to isolate.

Jobs, Events, Listeners. Everything that can be async — make async. Sending email, PDF generation, external API sync, aggregate recalculation — into Queue. Laravel Horizon for queue monitoring in Redis: see throughput, failed jobs, processing time per queue.

How Octane handles high load

Laravel Octane with RoadRunner or Swoole keeps the app in memory between requests — removes bootstrap overhead (config loading, class autoloading) on each HTTP request. Gain: 3–8x on synthetic benchmarks, 2–4x on real applications. Important: no state between requests in static variables — that leads to exactly the incidents from the beginning. We use this in projects with >1000 RPS.

What to do about N+1 queries

N+1 is the most common cause of slow pages in Laravel apps. Standard story: page worked fine on dev with 10 records, on production with 10,000 — 8-second load.

Laravel Debugbar in dev environment shows the number of queries per page. More than 20 queries per page — signal for audit.

Model::preventLazyLoading(! app()->isProduction());

Telescope for profiling in staging: logs all queries, jobs, mail, notifications with time detail. Numbers: after implementing eager loading, page load time drops from 8s to 0.3s — 27 times faster.

PostgreSQL: indexes that are actually needed

PostgreSQL 14+ is the primary DB on all projects. We use PgBouncer + PostgreSQL combination. 10+ years experience, more than 50 backend projects, 5 years on the market.

How PostgreSQL helps avoid slow queries

Composite indexes for frequent WHERE + ORDER BY. If you have WHERE user_id = ? AND status = ? ORDER BY created_at DESC — you need (user_id, status, created_at DESC). A separate index on (user_id) doesn't help much with sorting.

Partial indexes. If 95% of queries go with WHERE status = 'active':

CREATE INDEX idx_orders_active ON orders (created_at DESC)
WHERE status = 'active';

The index is small, fast, covers the main load.

GIN indexes for JSONB and arrays. @> operator without GIN index — seq scan. With index — fast even on millions of rows.

GIN for full-text search. to_tsvector + GIN instead of LIKE '%query%'. LIKE without index is always seq scan. With pg_trgm extension and gin_trgm_ops — supports LIKE with index, useful for CRM search by partial match.

Connection pooling: why it's more important than it seems

Rails, Laravel, Django open a new connection to PostgreSQL for each PHP/Python process. With 100 workers — 100 connections. PostgreSQL starts degrading from 200–300 active connections — overhead on connection management becomes significant.

PgBouncer — connection pooler in front of PostgreSQL. Transaction pooling mode: connection to PostgreSQL is occupied only during a transaction, returned to pool between requests. 1000 application workers → 20–50 actual connections to PostgreSQL. This reduces latency by 40% and hosting costs by 30%.

Node.js with Fastify: when it's better than Laravel

Node.js is justified for:

• Realtime: WebSocket servers, Server-Sent Events, chat, live updates
• Streaming: large files, video, streaming data
• High I/O concurrency: many parallel requests to external APIs without heavy business logic
• Serverless: Lambda/Cloud Functions — Node.js starts faster than PHP

Fastify over Express: 2–3 times faster on benchmarks, built-in JSON Schema validation, better TypeScript support, plugin architecture.

Typical realtime architecture: Laravel — core business logic and REST API. Node.js + Socket.io or ws — WebSocket server. Laravel publishes events to Redis Pub/Sub, Node.js subscribes and broadcasts to clients. This separation allows scaling the WebSocket server independently of the main app.

Go: microservices and high load

Go we use for:

• High-load microservices (>10,000 RPS)
• Background workers with strict latency requirements
• DevOps tools and CLI
• gRPC services in microservice architecture

Goroutines — thousands of times cheaper than OS threads. 10,000 concurrent connections on Go is normal on one server.

But Go is not a silver bullet. Development is slower than Laravel: more boilerplate, no ORM at Eloquent level, error handling with if err != nil everywhere. Justified only when performance is a real requirement, not an assumption.

Django and Python backend

Django with DRF (Django REST Framework) — for tasks where Python is needed: ML pipelines, data processing, integrations with AI tools.

Celery for background tasks — similar to Laravel Queue but more complex to configure. Celery Beat for cron tasks.

Django ORM vs raw SQL: ORM is convenient for CRUD. For analytical queries with multiple JOINs, window functions, and CTEs — connection.execute() with raw SQL is more readable and predictable.

Redis: not just cache

Redis in our projects plays multiple roles:

Redis Cluster for horizontal scaling. Sentinel for automatic failover on standalone setups.

Deployment and infrastructure

Docker + docker-compose — standard for local development and production. Each service in a container: PHP-FPM/Octane, Nginx, PostgreSQL, Redis, Queue Worker, Scheduler.

CI/CD via GitHub Actions:

1. Run tests (PHPUnit / Pest, Vitest, Playwright)
2. Build Docker image
3. Push to Container Registry
4. Deploy: docker pull → docker-compose up -d on server, or Kubernetes rolling update

Zero-downtime deploy for Laravel: php artisan down --secret=TOKEN is not needed with proper configuration. Strategy: new container starts next to the old one, Nginx switches traffic after health check, old container stops.

Monitoring: Sentry for exception tracking with alerting in Slack/Telegram. Grafana + Prometheus (or Grafana Cloud) for metrics: CPU, memory, request rate, queue depth, database connection count. Alerts on: error rate > 1%, p99 latency > 2s, queue depth > 1000 jobs.

What's included in turnkey work

• Architecture design (API documentation, DB schema, service diagram)
• Implementation according to agreed specification with code review
• CI/CD, monitoring, alerting setup
• Load testing (k6, wrk) with report
• Handover of source code, access, deployment instructions
• Training of customer's team (2-3 sessions)
• Warranty support for 1 month after delivery

Timeline benchmarks

Pricing is calculated individually after analyzing load, integrations, and business logic. Contact us for a free audit of your current backend — get an optimization plan in 2 days. Request a consultation.