Craft CMS
What we do:
ExpressionEngine and Craft CMS, exclusively, since 2007. Version upgrades, long-term retainer support, taking over from agencies, third-party integrations including Stripe, Salesforce and HubSpot, and legacy PHP maintenance. Every project is handled personally by Karl. You deal directly with Karl, from first call to final delivery.
Platform
Craft CMS Maintenance, Upgrade & Support
Specialist support, maintenance, and upgrades for business-critical Craft CMS websites. Extensive hands-on platform experience, all work handled personally by Karl.
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Platform
ExpressionEngine Maintenance, Upgrade & Support
Specialist support, maintenance, and upgrades for business-critical ExpressionEngine websites. Close to two decades of hands-on platform experience, all work handled personally by Karl.
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Platform
Custom PHP & Laravel Development
Bespoke PHP application development and Laravel project work, from new builds and third-party integrations to extending and modernising existing custom-built applications.
Find out moreTrusted by established businesses and growing brands across the UK
Expression 37 works with a small number of clients at any one time. These are some of them.



What we have worked on:
Every client came with a real problem and a website they could not afford to have fail. Here are a selection of the engagements and what was involved in each.
Craft CMS
Custom PHP
City Permits
ExpressionEngine
Graham Sanderson Interiors
What we write about:
Practical writing on ExpressionEngine, Craft CMS, and the kind of problems that build quietly until they can no longer be ignored. Written for business owners, not developers.
Taking Over a Craft CMS Site Built by Another Developer: What We Look for First
A meaningful part of the work we do at Expression 37 involves inheriting Craft CMS sites that were built by developers or agencies who are no longer involved. The circumstances vary, but the practical challenge is always similar: a site you didn’t build, with code you didn’t write, and decisions that were never documented.
Third-Party Integrations on Craft CMS: Why They Break and What to Do About It
If your Craft CMS site connects to any external service, whether that’s Stripe for payments, HubSpot or Salesforce for CRM, or Mailchimp for email, you have a dependency that you probably don’t think about until it fails. Integrations break. Here’s why they fail and what to do about it.
What to Look for When Hiring a Craft CMS Developer
Craft CMS has a strong but relatively specialised developer community. The difference between someone who has built seriously with Craft and someone who has touched it once or twice is meaningful. If your site runs on Craft and you need ongoing development or support, knowing what to look for matters.
About Karl
Karl is the founder of Expression 37 Ltd and has been working exclusively with ExpressionEngine and Craft CMS since 2007. In eighteen years he has supported more than 80 clients across the UK, from long-term retainer arrangements to emergency rescues when something has gone wrong at the worst possible moment. Every piece of work is handled personally by Karl, with no account managers or junior developers between you and the person doing it.
Find out how we workClient feedback:
Karl has been instrumental in delivering the ExpressionEngine development requirements for our client. Karl very quickly became part of our extended team as he is reliable, dependable and thorough in everything he does. Karl has a genuine desire to see his clients succeed and he will go out of his way to help them achieve that. Karl worked hard on our projects and was so helpful all along the way. He is driven, talented and an absolute pleasure to work with! Any organisation would be lucky to have Karl on their team.
Leilah Aintaoui
Video Smart Ltd.