Magento development agency: the diligence checklist, the editions, and what drives the cost

A Magento development agency builds and maintains stores on Magento Open Source or Adobe Commerce, the paid edition Adobe has owned since its 2018 acquisition of Magento. Hiring one is mostly a technical diligence exercise, because the platform rewards disciplined engineering and punishes shortcuts: it is a large PHP application with a module system, a declarative schema, a search dependency on Elasticsearch or OpenSearch, a full page cache usually fronted by Varnish, and a security patch cycle you have to keep up with. The four things worth checking before anything else are whether they install modules through Composer rather than editing core files, whether they work in Git with a staging environment, how they handle Adobe's patch releases, and who holds the Adobe certifications on the team.

This page covers the editions, what the agency has to own, how to judge a shortlist and what drives the cost. For the configuration and search side of the platform, see our guide to Magento 2 SEO.

Which edition you are actually on

Edition	What it is	What it means for the agency brief
Magento Open Source	The free, self hosted edition	You buy hosting, extensions and all development. The agency owns upgrades and security patching.
Adobe Commerce	The licensed edition, with B2B features, staging, advanced reporting and support	Licence from Adobe, implementation from the agency. Ask which licensed features you are paying for and actually using.
Adobe Commerce on cloud infrastructure	Adobe's managed platform as a service deployment	Deployment and environments are governed by Adobe's pipeline, so the agency needs real experience of it

Magento 1 reached end of support in June 2020, so any store still on it is running unpatched. If that is you, the brief is a replatform rather than a maintenance engagement, and the first conversation is about data migration and URL preservation.

Adobe publishes the admin documentation on Experience League and the developer documentation at developer.adobe.com/commerce. Both are worth skimming before a pitch so you can tell a specific answer from a vague one.

What the agency has to own

• Engineering discipline. Composer based dependency management, no modifications to core files, coding standards enforced in continuous integration, code review, and a documented branching model.
• Environments. Local, staging and production, with a repeatable deployment and a tested rollback. Content and configuration moved through deployment rather than by hand in the admin.
• Security and patching. A schedule for Adobe's security releases, a tested patch process and a record of which patches are applied. This is the most common gap in inherited builds.
• Performance. Full page cache, Varnish, Redis for sessions and cache, indexers on schedule, image handling, and a measured view of Core Web Vitals on category and product templates.
• Search and merchandising. Elasticsearch or OpenSearch configured properly, synonyms, stopwords, faceting that does not generate an infinite URL space, and category rules merchandisers can use without a developer.
• Integrations. Enterprise resource planning, product information management, payments, tax, shipping and marketing platforms, each with error handling and a monitoring alert rather than a silent failure.
• Multi store structure. Websites, stores and store views set up to match how you actually sell by brand, country and language, because getting this wrong is expensive to undo.
• Handover documentation. Architecture notes, module inventory with versions, runbooks and admin training.

How to judge a shortlist

• Ask for the Adobe partner level and the certifications held, by name. Adobe runs a solution partner programme with tiers and an individual certification path for Adobe Commerce. Ask how many certified developers would be on your team, not in the company.
• Ask to see a module they wrote. You are looking for a self contained Composer package with tests, not a patched core.
• Ask how they handle upgrades. A credible answer names the cadence, the regression testing approach and how third party extension compatibility is checked before the upgrade, not after.
• Ask about their worst launch. Every agency with real Magento experience has one. What they fixed and what they changed afterwards tells you more than a case study.
• Ask who owns the repository, the servers and the extension licences. All three should be yours, in your accounts, from day one.
• Ask for the extension policy. Good agencies keep the extension count low and justify every one, because each module is future upgrade work.
• Ask what the support arrangement covers. Response times, who is on call, what counts as an incident, and what sits outside the retainer.
• Ask for a reference you choose. Pick a client from their site rather than accepting the one they offer.

Magento against the alternatives, fairly

Magento and Adobe Commerce earn their place where catalogue complexity, pricing rules, multi store structure or business to business requirements exceed what a hosted platform does natively. Shopify Plus and BigCommerce trade that flexibility for far lower operational burden, since the platform handles hosting, patching and upgrades. Commercetools and other composable platforms suit teams who want to assemble their own front end and services.

A practical test: list the five things your store does that a standard hosted platform would make awkward. If the list is long and specific, Magento is a sound choice. If you struggle past two, the operational savings elsewhere are probably worth more than the flexibility. Our comparison of the four ecommerce agency capability stacks covers how to judge the build team whichever platform you land on.

What drives the cost

• Catalogue and data complexity. Attribute sets, configurable products, pricing rules and the state of your product data.
• Integrations. Each connected system is scoped work, and the quality of the other system's interface matters more than Magento does.
• Front end approach. A themed Luma based build, a custom theme, or a decoupled front end using GraphQL are three very different budgets.
• Number of stores and languages. Each store view adds content, testing and translation work.
• Migration scope. Customers, orders, products, content and URLs, plus the redirect map, which is a deliverable in its own right.
• Ongoing maintenance. Patching, upgrades, monitoring and support, priced as a retainer with hours stated.

Ask every bidder to price the same itemised deliverables list, in hours, so the quotes are comparable. A lower total with fewer hours on testing and patching is not a saving.

Questions merchants ask

Is Magento still a good choice?

It is a strong choice for complex catalogues, business to business selling and multi store operations, and it has an active ecosystem under Adobe's ownership. It asks for engineering discipline and a maintenance budget, so buy it when the flexibility earns its keep and plan the upkeep from the start.

How long does a Magento build take?

Scope drives it far more than the platform does. A replatform with integrations and data migration runs in months, with discovery, build, integration, content, testing and a launch window. Ask for the plan broken into phases with a deliverable at the end of each, so progress is visible.

Do I need Adobe Commerce or will Open Source do?

Open Source covers a great deal, and plenty of successful stores run on it. Adobe Commerce adds the licensed features such as business to business functionality, staging, advanced reporting and vendor support. Price both, list the licensed features you would genuinely use, and decide on that list.

Can I move from Magento 1?

Yes, and it is a rebuild rather than an upgrade, because the architecture changed. Treat data migration and URL preservation as first class workstreams, and build the redirect map from a full crawl of the existing site before launch.

What should the maintenance retainer include?

Security patching, platform and extension updates, monitoring and alerting, a defined number of development hours, and a named response time for incidents. Ask what happens when an urgent security release lands outside your sprint.

How do I avoid being locked in to one agency?

Own the repository, the hosting accounts and the extension licences, insist on documentation and a module inventory, keep core untouched, and ask for a handover pack as a standing deliverable rather than something produced at the end.

One store check that is not in the admin

When you diligence an agency, you look at the admin, the code and the hosting. Ask the agency to do one more thing: ask an assistant for stores selling your product type and see whether your store is named, and what it is said to offer.

The answer depends on feeds, markup, reviews and category pages, all things a Magento agency touches. An agency that takes the check seriously understands that discovery is part of the build. AI Knows Us provides a record of those answers that you can hand to the agency as a baseline.