1. Introduction: De-Risking Your Re-platforming
Migrating a website or web application is one of the most stressful technical projects a business can undertake. A botched CMS migration can obliterate your organic search rankings, alienate your user base with a poor UX, and drain your IT budget through endless scope creep.
Selecting the right development partner is paramount. You need an agency that writes clean code, understands the commercial implications of site speed, and—crucially—has a rock-solid QA and testing framework.
We have evaluated leading UK web development agencies based on their tech stack mastery, post-launch support, and proven ability to handle complex data migrations without data loss.
2. Agency Comparisons
Kyan is a technology agency that excels at building complex, custom web applications and digital products. They are not a standard 'brochure site' agency; they are engineers who partner with you to build scalable SaaS platforms or bespoke internal tools.
Key Strengths
Cyber-Duck is renowned for its rigorous, user-centred design process and strict adherence to accessibility standards. They are a safe pair of hands for government, healthcare, or financial sector projects that require deep compliance and secure data handling.
Key Strengths
For content-heavy publishers or mid-market e-commerce, Tom&Co offers exceptional expertise in the WordPress ecosystem. They specialise in transforming sluggish legacy sites into lightning-fast headless architectures or enterprise-grade WordPress builds.
Key Strengths
3. The Re-platforming Rulebook
When comparing these agencies, focus your questioning on the transition phase, not just the shiny new build.
- Ask about the Data Migration: How exactly will they map and transfer your existing user data or product catalogues? What is their rollback plan if the migration fails?
- Demand an SEO Retention Plan: The agency must provide a documented 301 redirect mapping strategy. If they say "SEO isn't our job," walk away. A site migration without SEO consideration is commercial suicide.
- Understand the Handoff: Will you be locked into their proprietary hosting, or will they provide clean, commented code via a Git repository that your internal team can eventually manage?
For a deeper dive into contractual traps, review our guide on SaaS and Software Contract Red Flags before signing a Master Services Agreement (MSA).