OnTheMarket Transforms the UK Property Search Experience with a Modern Digital Platform

Challenge

, the UK's third-largest property portal, was losing ground to competitors with faster, more intuitive search experiences. The legacy platform's search infrastructure returned results in 4–6 seconds on average — an eternity for users expecting instant results. Bounce rates on mobile were above 60%, and the property alert system sent bulk emails rather than personalised notifications.

The engineering team was constrained by an ageing monolithic architecture that made feature development slow and deployment risky. Every release required a full regression cycle that lasted weeks, stifling the pace of innovation needed to compete in a rapidly evolving market.

"Our competitors were shipping new features every fortnight while we were shipping every quarter," said OnTheMarket's CTO. "We needed to modernise without losing the platform that millions of users rely on every day."

Solution

Winklix executed a full platform rebuild using a modern React/Next.js frontend backed by a Node.js API layer and Elasticsearch-powered search, running on AWS. The migration was designed as a strangler-fig pattern to avoid any downtime during the transition. Delivery ran over 14 months.

Search Infrastructure Rebuild

Winklix replaced the legacy search layer with an Elasticsearch cluster tuned for property search — supporting geospatial queries, faceted filtering, and sub-500ms response times at scale. A relevance scoring model surfaced the most suitable properties for each user's search context.

Frontend & Mobile Experience

A new React/Next.js frontend delivered server-side rendered property listings for SEO performance, with a client-side interactive map search built for speed. The mobile experience was rebuilt from scratch using responsive design principles, reducing mobile bounce rate significantly.

Personalised Alerts & Agent Tools

A new property alert engine used saved search preferences and browsing behaviour to send personalised push and email alerts within minutes of a matching listing going live. A companion agent portal gave estate agents real-time visibility into listing performance and lead activity.

Outcome

Within three months of the new platform going live:

• Property search response time improved from 5 seconds to under 500ms.
• Mobile bounce rate reduced from 63% to 38%.
• Lead conversion rate increased by 33%.
• Property alert open rate improved by 47% through personalisation.
• Engineering deployment frequency increased from quarterly to weekly.