While he was an engineer at Facebook, Avinash Lakshman created Apache Cassandra, a 'big data' database originally built to handle Facebook's Inbox Search feature. Facebook gave Cassandra away as a free and open-source software project and it's now a very popular database used by oodles of companies. Lakshman went on to found Hedvig, which offers software that makes all of a company's computer storage systems act like one really big, really fast hard disk. Like Cassandra, Hedvig also runs on ordinary, low-cost x86-based servers.
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