Database management upstart DataStax has passed the 1,000-customer mark, including one-third of the Fortune 100, a milestone that influenced a key new alliance with technology giant Hewlett-Packard.

Under the new relationship, the two companies have created a scalable, purpose-built solution for big data applications that pairs DataStax Enterprise software with HP Moonshot high-end server hardware. The technology will be sold jointly by DataStax and the HP corporate sales team, further boosting the five-year-old upstart’s credibility in big accounts.

“Organizations trying to manage today’s data deluge with legacy technology face many challenges—such as lagging response times, escalating IT costs and limited scale-out capabilities,” said Susan Blocher, vice president of marketing and business development for HP Moonshot, commenting on the pact. “The predictability of DataStax Enterprise software and the scalability of HP Moonshot servers enables our joint customers to handle large amounts of data with exceptional performance and continuous.”

DataStax CEO Billy Bosworth wouldn’t share pricing for the system, which is available immediately. The cost takes the form of annual subscription based on how many central processing units (CPUs) are used to run the software.

The DataStax database platform is based on the open source Apache Cassandra project, and it used by high-profile companies including Adobe, eBay, Intuit, Netflix, Safeway and Target. Overall, at least 500 big corporate accounts and 500 startups are using the DataStax technology, according to the company.

“If you look at our top 10 customers, there is no company that represents more than 10% of our business,” Bosworth told Fortune. “That is an important metric. We’re finding traction in retail, finance, media, government and healthcare.”

Target, for example, relies on DataStax for its distributed digital commerce strategy. “Apache Cassandra scales, can ingest huge amounts of data, can replicate across multiple data centers, and ensures continuous uptime,” Target technology expert Dan Cundiff said in a case study explaining the project. “We listened to the community and experts, and realized that we also wanted access to DataStax’s expert support and services, as well as enterprise functionality such as security, analytics and search.”

When Bosworth joined DataStax in 2011, the company had around 19 employees; its workforce is now well over 400 people. DataStax closed a $106 million funding round last September, when it was valued at around $830 million. Its biggest legacy competitor is Oracle, but it also faces stiff competition from two other well-funded database startups, MongoDB ($231 million total) and Couchbase ($115 million).

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