Klevu - Klevu offers instant site search solution for eCommerce stores.
Dynamic Yield - Personalization & customer experience management
Algolia - Algolia's Search API makes it easy to deliver a great search experience in your apps & websites. Algolia Search provides hosted full-text, numerical, faceted and geolocalized search.
Sailthru - Sailthru Smart DataTM technology enables businesses to optimize, automate, and deliver personalized experiences to each individual at scale.
Google Custom Search - Google Custom Search enables you to create a search engine for your website, your blog, or a collection of websites.
Lytics - Lytics is a company that utilizes machine learning to collect and analyze data to help you find new approaches to marketing. They offer unique and customized experiences to each customer. Read more about Lytics.