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Magento Extension Development · London

Magento Extension Development in London

Building Magento extensions for London retailers, where the mechanism chosen determines what upgrades cost later. Magento offers several ways to change behaviour, and the one that looks simplest — replacing a core class outright — is the one that makes every future release a manual reconciliation.

Why this comes up

The problem

Custom behaviour was added by replacing core classes, and each upgrade now requires reviewing all of them.

What you get

What we deliver

  • Behaviour extended through plugins rather than by replacing core classes
  • Preferences avoided except where genuinely no alternative exists
  • Events used where the requirement is to react rather than to alter
  • Compatibility considered against the extensions already installed
  • Configuration exposed in the admin where merchants should control it
  • Module documented and versioned, since it becomes part of your upgrade path

Want this scoped for your business in London?

Thirty minutes, no charge, no sales script. You leave with a written summary of what magento extension development would actually involve — whether or not you use us.

Book a 30-minute call

Working in London

London

London clients usually come to us because they want senior people actually on their project rather than a large agency's B team, and because Midlands rates buy considerably more delivery per pound.

Clients here are usually replacing an agency, and want senior people on the work at rates that are not Central London rates.

Sectors we work with in London

  • Financial Services
  • Professional Services
  • Technology
  • Media
  • Hospitality
  • Retail

What we work with

Technologies and platforms

  • Magento 2
  • PHP
  • Composer
  • XML

Who we work with

Industries we serve

  • Wholesale
  • Manufacturing
  • Retail
  • Distribution
  • Trade suppliers

Why us

Why London businesses choose Asionis

  • Projects typically launched within 4–8 weeks
  • No long-term contracts required
  • All team members UK-based
  • Dedicated account manager and development team
  • Transparent reporting with monthly performance metrics
  • Scalable from startup to enterprise

How we work

  1. Step 1

    Free consultation

    A 30-minute call to understand the problem. You keep the written summary either way.

  2. Step 2

    Proposal

    Scope, timeline and a fixed price, in writing, before anything starts.

  3. Step 3

    Build

    Short cycles with regular check-ins, so you see progress rather than hear about it.

  4. Step 4

    Launch and support

    We handle the go-live and stay available afterwards.

Magento Extension Development in London — common questions

What is wrong with class preferences?
They replace the original entirely. Your copy is frozen at the version it was written against, so every core fix and change to that class is silently lost — and each release then requires somebody to compare the two and reconcile them by hand.
What should be used instead?
Plugins, which intercept a method without replacing it. They let core code continue evolving underneath while your behaviour runs before, after or around it, which is the difference between an upgrade that applies cleanly and one that needs a developer for each module.
When are events the right choice?
When you need to react rather than to change a result. Sending a notification or writing a record after something happens suits an observer, and it is the loosest coupling available — which makes it the most durable option where it fits.
Do two extensions ever conflict?
Frequently, and it is worth checking deliberately. Multiple plugins on the same method run in a sequence determined by configuration, so behaviour depends on ordering that nobody set intentionally — testing against the store's actual module set is the only way to know.
Do you work with businesses across Greater London?
Yes. We are based in Leicester, United Kingdom and work with clients throughout London, including London and the surrounding Greater London area. Most collaboration happens remotely, and we travel for kick-offs and key milestones.
What kind of London businesses do you usually work with?
Clients here are usually replacing an agency, and want senior people on the work at rates that are not Central London rates. Beyond that we work across Financial Services, Professional Services, Technology, Media, Hospitality and Retail.
Do you cover the areas around London?
Yes — we work throughout London, including Reading, Milton Keynes, Cambridge, Brighton. London is an urban area of roughly 9,000,000+, and we take on work across the wider Greater London region rather than the city boundary alone.

Talk to us about Magento Extension Development in London

A 30-minute call with someone who would actually work on it. No sales script, no obligation.

  • Projects typically launched within 4–8 weeks
  • No long-term contracts required
  • All team members UK-based
  • Dedicated account manager and development team
  • Transparent reporting with monthly performance metrics
  • Scalable from startup to enterprise

Or reach us directly

07707 771599admin@asionis.com

Leicester, United Kingdom