CodeIgniter 3 to 4 conversion
Controllers, models, libraries, and views ported to CodeIgniter 4, with your routes and business rules kept.
The Problem
Your CodeIgniter 3 App Is Stuck on an Old PHP Version
CodeIgniter 3 last shipped in March 2022 and now gets mostly security updates. CodeIgniter 4 needs PHP 8.2 or newer, and it isn't a drop-in upgrade, so many apps sit in between.
01 · Old PHP
The app can't move past PHP 8.1 without errors.
We convert it to CodeIgniter 4, which runs on PHP 8.2 or newer.
02 · No tests
Nobody knows which pages break after a change.
PHPUnit tests on key routes run before and after every conversion step.
03 · Homemade login
Sign-in code was written years ago and hasn't been reviewed since.
Login moves to CodeIgniter Shield, the framework's official authentication library.
04 · Schema drift
Database changes were made by hand on the live server.
Spark migrations record every table change, so staging and live databases match.
Your CodeIgniter 3 app has run orders, bookings, or member records for years. Its last framework update was version 3.1.13, from March 2022, and PHP 8.1 stopped getting security fixes at the end of 2025. Your host keeps nudging you toward a newer PHP, and every trial upgrade fills the logs with warnings. Nobody wrote tests, so nobody knows which pages would break. The developer who built it has moved on, and the login code hasn't been reviewed in years.
We start with tests, not code changes: PHPUnit checks on the routes your business depends on. Then we convert the app to CodeIgniter 4 module by module on staging, move login to CodeIgniter Shield, and record the database in Spark migrations. Your URLs and business rules stay the same, and the tests prove it. You end up on a current release, not a rewrite you didn't need.
Tests before any change
PHPUnit route tests capture how the app behaves today, so the conversion can be checked.
Login on CodeIgniter Shield
Sign-in, password resets, and permissions move to the official CodeIgniter authentication library.
Converted one module at a time
Controllers, models, and views move to CodeIgniter 4 one module at a time on staging.
Our CodeIgniter Development Process
From an Untested App to a Current Release in Five Steps
Five steps take your app from an untested CodeIgniter 3 or older 4.x codebase to the current release. You approve the plan, see each module on staging, and choose the switch-over date.
You give us read access or walk us through the app. We check the CodeIgniter version, the PHP version on your server, and the riskiest code. You get a short findings note and a fixed-price proposal.
What's Included
What Is CodeIgniter Development?
CodeIgniter development is building and maintaining PHP apps on the CodeIgniter framework. With us, it means CodeIgniter 4 conversions, version upgrades, new modules, and the tests that keep them safe.
Compare Options
DeveloperLook vs a Laravel Rewrite vs Staying on CodeIgniter 3
Staying on CodeIgniter 3 costs nothing today, and a Laravel rewrite suits apps that need its larger package ecosystem. When you hire CodeIgniter developers to convert instead, your logic and team habits stay.
| Feature | DeveloperLookBest fit | Laravel rewrite | Stay on CI3 |
|---|---|---|---|
| Planning | Route-by-route conversion plan | New architecture from scratch | No plan needed |
| First result | About 2 weeks for an upgrade | Months before anything ships | Nothing to wait for |
| Business logic | Kept, ported, and tested | Rewritten and re-tested | Untouched |
| Testing | PHPUnit tests on key routes | New test suite | Usually none |
| PHP version | PHP 8.2 or newer | PHP 8.3 or newer | Stuck on older PHP |
| Package ecosystem | Shield, Spark, and Composer packages | Broad Laravel package ecosystem | Frozen feature set |
| Team learning curve | Familiar CodeIgniter patterns | New framework to learn | None |
| Cost | Fixed price per scope | Highest upfront cost | Lowest today, rising risk |
DeveloperLook
Laravel rewrite
- Planning
- DeveloperLook: Route-by-route conversion planLaravel rewrite: New architecture from scratch
- First result
- DeveloperLook: About 2 weeks for an upgradeLaravel rewrite: Months before anything ships
- Business logic
- DeveloperLook: Kept, ported, and testedLaravel rewrite: Rewritten and re-tested
- Testing
- DeveloperLook: PHPUnit tests on key routesLaravel rewrite: New test suite
- PHP version
- DeveloperLook: PHP 8.2 or newerLaravel rewrite: PHP 8.3 or newer
- Package ecosystem
- DeveloperLook: Shield, Spark, and Composer packagesLaravel rewrite: Broad Laravel package ecosystem
- Team learning curve
- DeveloperLook: Familiar CodeIgniter patternsLaravel rewrite: New framework to learn
- Cost
- DeveloperLook: Fixed price per scopeLaravel rewrite: Highest upfront cost
Projects We've Built
Booking, Store, and Community Sites We Have Built
Booking, ecommerce, investment, and review community websites from our portfolio, picked for their forms and admin-managed content, not shown as CodeIgniter builds.
Destinata Luxury Limousine Booking Website
- Logistics & Transportation
- Automotive
- Booking System
Borna's General Hardware Ecommerce Website
- Retail
- E-commerce
- Website
Envitis Investment Website Design & Development
- Finance
- Dashboard
- Website
Airline Review Community Website for Business and First Class
- Travel
- Portal
- Website
What Our Clients Say
What Clients Say After Launch
Feedback from teams we have built PHP websites and web apps for.
We had a pretty specific idea of what we wanted our website to become, but I wasn’t sure how easily we could explain all of it to a development team. There were quite a few moving parts, and we were working toward a deadline, so I expected a few things to get lost along the way. That never really happened. They understood what we were trying to achieve, kept us updated throughout the process, and got everything ready within the agreed timeline. The final site feels much easier to navigate, works beautifully on mobile, and is noticeably smoother for our customers. It was a huge relief seeing the original idea actually turn into the website we had in mind.
The mobile experience is probably my favourite part of the new site. We had spent a lot of time making sure the desktop version looked right, and the team kept pushing us to think about how everything would actually feel on a phone too. They were right. The navigation is clean, the interactions feel natural, and everything we’ve tested so far works exactly as it should. They also went through the links, forms, integrations, and other details more than once before launch, which I really appreciated. And even after going live, we could still reach out when something came up. The whole process felt friendly, organised, and surprisingly straightforward.
What I appreciate most is that the website is actually easy for us to manage now. We can update content ourselves instead of sending a developer a message every time we need to change something small. They also paid attention to the technical SEO side, which mattered to us because we didn’t want a new website to create problems for the traffic we already had. I’ve probably asked more questions than I should have since launch, but every question has been handled patiently and without any fuss. The team is easy to work with, they explain things clearly, and when we need something changed, they focus on getting it done rather than making the process complicated.
1,250+
Projects shipped
10+
Years of experience
Top 3%
Upwork Top Rated Plus
5 stars
Average review score
Want results like these?
Tell us what you are building. You get a reply within 24 hours on business days, then a written estimate.
Work Culture
Why Business Owners Trust Us With CodeIgniter Apps
Old CodeIgniter apps often carry years of business rules nobody wrote down. These habits keep those rules intact while the code underneath gets current.
Tests come first
We write PHPUnit tests on your key routes before we change a line. The tests show the converted app does what the old one did.
Old URLs keep working
Every route in the old app is mapped before conversion starts. Bookmarks, links in emails, and search results still land on the right page.
Business rules written down
When we find logic nobody documented, such as a discount rule hidden in a helper, we write it down. You get a record of how your app actually works.
Honest about Laravel
If your app needs packages only Laravel offers, we say so in the proposal. Converting to CodeIgniter 4 only makes sense when it fits your plans.
One planned switch-over
The new version goes live in one scheduled release with a rollback ready. Your team knows the date and what to check afterwards.
Your code, your server
Code lives in your repository and runs on your hosting account. Our access ends at handover unless you ask us to stay on.
Overview
When does it make sense to hire CodeIgniter developers?
DeveloperLook helps you hire CodeIgniter developers to convert CodeIgniter 3 apps and upgrade older CodeIgniter 4 apps to the current release on PHP 8.2 or newer. We write PHPUnit tests on key routes first, then port the code and move login to Shield. Prices start at $900, upgrades take about 2 weeks, and conversions 5 to 14 weeks.
DEVELOPERLOOK
Project facts · CodeIgniter Development Services
- Service
- CodeIgniter Development Services (CodeIgniter 4 conversions, upgrades, new modules)
- Typical timeline
- About 2 weeks for an upgrade, 5 to 14 weeks for a conversion or new app
- Platforms
- CodeIgniter 3 and 4 apps on PHP 8.2+ with MySQL or MariaDB
- Built with
- CodeIgniter 4, Shield, Spark, PHPUnit, and Composer
- Experience
- 10+ years of development experience and 1,250+ shipped projects
- Post-launch support
- 30 days, or 60 days on the CI4 App Build plan
- Communication
- Calls in US, UK, and AU business hours
- Starting price
- From $900 USD, fixed scope after discovery
Reviewed 10 Oct 2026 by Saimul Islam
Good fit
Owners of a CodeIgniter 3 app
Your CodeIgniter 3 app still runs the business, but your host wants you off PHP 8.1 and nobody wants to touch the code.
Teams on an older CodeIgniter 4
You're on an early 4.x release and need the current version and PHP 8.2 before your next server upgrade.
Teams who prefer a small framework
You want a new PHP app without a heavy framework, and you need CodeIgniter developers for hire who write tests from day one.
Companies that inherited CodeIgniter code
Your original developer left, and you need a CodeIgniter development company to read the code, fix what's risky, and keep it running.
Agencies with CodeIgniter clients
Your agency maintains client sites built on CodeIgniter and needs a CodeIgniter web development company working quietly under your brand.
Not a fit
Moving to Laravel anyway
You've already decided on Laravel and want the app rebuilt there. Our Laravel Development Services page covers that rebuild.
Plain PHP, no framework
Your app is plain PHP without a framework and needs a PHP 8 upgrade. Our PHP Development Services page handles that work.
Large multi-team platform
You're planning a long-lived platform with several teams and long support windows. Our Symfony Development Services page is the closer match.
Budget under $900
Your budget is under $900, or a CMS could replace the app entirely. That costs less, and we'll tell you before we quote.
Not sure we're the right fit?
Book a free call or message us. We'll tell you honestly whether we're the right team.
Pricing
Transparent Starting Prices for CodeIgniter Development Services
These are starting points in USD. Your final price depends on the number of controllers, the version you start from, and integrations, and you get a fixed proposal after a free code review call.
For an app on an older CodeIgniter 4 release that needs the current version. About 2 weeks.
$900one-time, USD
- One CodeIgniter 4 app moved to the current release
- Runs on PHP 8.2 or newer
- Composer dependencies updated and audited
- PHPUnit tests on up to 10 key routes
- Deprecated calls fixed per the upgrade guides
- 30 days of post-launch support
Recommended
For a CodeIgniter 3 app with up to 15 controllers. About 5 to 8 weeks.
$3,200one-time, USD
- Everything in CI4 Upgrade Sprint
- Up to 15 controllers converted to CodeIgniter 4
- Login moved to CodeIgniter Shield
- Database changes as Spark migrations
- Old routes mapped and kept
- One planned switch-over release
For larger CodeIgniter 3 apps with up to 40 controllers, or a new CodeIgniter 4 app. About 9 to 14 weeks.
$6,800one-time, USD
- Everything in CI3 to CI4 Conversion
- Up to 40 controllers, or a new app
- REST API with Shield access tokens
- Roles and permissions with Shield groups
- Up to 3 integrations with outside services
- 60 days of post-launch support
For Agencies
White-Label CodeIgniter Development for Agencies and Studios
You keep the client relationship. We supply the CodeIgniter web development services behind it: upgrades, CodeIgniter 4 conversions, and new modules under your brand. Your client gets tested code in their repository and a clear switch-over plan.
How the partnership works
White label: your client only ever sees your brand
- Your client
- You, the agency
- DeveloperLook
Share the brief
Send repository access, the server's PHP version, and your client's deadline.
- Client needs
- You share the details
- Details received
We review and quote
You get a findings note, a route inventory, and a fixed price to resell.
- Scope and plan
- Proposal to resell
- Your quoteYOUR LOGO
Convert and hand off
We convert on staging, switch over in your client's hosting, and document it.
- Done by our team
- Your brand on it
- Handed to your clientDone
Partner with DeveloperLookDelivered under your brand
Stay client-facing
Findings notes, staging links, and release notes carry your brand.
Predictable delivery
Fixed scope per module, with a route inventory agreed up front.
Senior PHP engineers
CodeIgniter, PHPUnit, and PHP 8 work from experienced developers.
Flexible capacity
One upgrade, a full conversion, or ongoing CodeIgniter maintenance work.
The Right Technology for Your Project
Technology Stack
CodeIgniter 4 and its official tools, the databases most CodeIgniter apps run on, and the testing and hosting setup we hand over with every release.
- CodeIgniter
PHP- Composer
- CodeIgniter Shield
- Spark CLI
MySQL- MariaDB
PostgreSQL- Redis
- PHPUnit
- GitHub Actions
- Postman
- Sentry
- Nginx
- Apache
Docker
AWS- DigitalOcean
FAQ
Frequently Asked Questions
Straight answers on CodeIgniter costs, versions, PHP support, and whether the framework still makes sense.
Saimul IslamFounder & CEO, DeveloperLookStill have questions?
Send a message or book a call with the team.
Hiring CodeIgniter developers through DeveloperLook starts at $900 for upgrading one CodeIgniter 4 app to the current release. Converting a CodeIgniter 3 app with up to 15 controllers starts at $3,200, and larger conversions or new CodeIgniter 4 apps start at $6,800. Every plan includes PHPUnit tests on key routes. You get a fixed quote after a free code review call.
CodeIgniter is an open-source PHP web framework known for its small footprint and short learning curve. It follows the model, view, controller pattern and ships with routing, database tools, form validation, and sessions. The CodeIgniter Foundation maintains it, and the current major version is CodeIgniter 4.
CodeIgniter is used for PHP web apps that need custom logic without a heavy framework: booking systems, member portals, internal dashboards, and REST APIs. Many businesses also use it for CodeIgniter website development where pages need forms, logins, or custom data. Very large platforms with many teams often pick Laravel or Symfony instead.
CodeIgniter sends every request through one front controller, which matches the URL to a route and calls a controller method. The controller loads data through models and passes it to a view, which renders the page. In CodeIgniter 4, filters run before or after controllers for checks such as login or CSRF protection.
The latest version of CodeIgniter is 4.7.5, released on October 9, 2026, and the 4.7 series requires PHP 8.2 or newer. CodeIgniter 3 stopped at version 3.1.13 in March 2022 and now receives mostly security updates. Check the official changelog before you upgrade, because new point releases arrive regularly.
Yes, CodeIgniter 3 runs on PHP 7, because its official requirement is PHP 5.6 or newer. Version 3.1.12 also added PHP 8.0 and 8.1 compatibility. The catch is that PHP 7 and PHP 8.1 no longer get security fixes. A CodeIgniter 3 app has no officially tested path to a supported PHP version, which is the main reason to convert.
Yes, CodeIgniter is still relevant for small and mid-sized PHP apps where quick setup matters more than a huge package ecosystem. CodeIgniter 4 gets regular releases, includes an official login library called Shield, and runs on current PHP. For apps that depend on many ready-made packages, Laravel is often the better pick.
No, CodeIgniter is not dead: CodeIgniter 4 is actively developed, with several releases during 2026. What has slowed down is CodeIgniter 3, which its maintainers describe as being in maintenance with mostly security updates. If your app is still on version 3, that's the part to plan for, not the framework as a whole.
Use CodeIgniter for development when you want a small, well-documented PHP framework with little configuration. It suits teams that already know PHP and apps on modest hosting. If you already run a CodeIgniter 3 app, converting to version 4 keeps your team's patterns and saves you from learning a whole new framework.
We can't rank other agencies fairly, but we can tell you what to check before you hire one. Ask for a CodeIgniter 3 to 4 conversion they've done, how they test routes before changing code, and whether they use Shield or homemade login. A good CodeIgniter development company also tells you when Laravel would serve you better.
Saimul IslamFounder & CEO, DeveloperLookStill have questions?
Send a message or book a call with the team.
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