A bit about the tech running EHarmony… Custom-built with enterprise Java tools and running on Resin, an open-source application, the site takes the answers to your questionnaire and stores them in a Microsoft SQL database as a “psychological profile.” Then, on a nightly basis, using a series of algorithms, it compares your profile with the profiles of all other active users (currently, around 900,000 people are active at any given time) and spits out a list of people with similar tastes, characteristics, attitudes, and values.
Once this process is complete, the site uses SendMail, an open-source e-mail gateway, to alert you to new matches, and you’re able to contact these people — and only these people — via an anonymous communication tool back on the site.
Eharmony is up to 4.5 million members, with around 10,000 signing up each day.
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