Bitstamp, which bills itself as the world's longest-running cryptocurrency exchange, is expanding in the U.S. market with an increased financial commitment to the region as it hires more talent and bolsters its market infrastructure.That will give U.S.-based crypto exchanges Coinbase (COIN) and eToro (ETORO) a run for their money.The Luxembourg-based company said new customers in the U.S. rose by more than six-fold in the first four months of 2021, with a 281% increase in assets under management, 348% increase in client activity, and 325% increase in mobile app usage.Bitstamp is working with U.S. financial companies, including Nasdaq (NDAQ) and Silvergate Bank (SI), to build market infrastructure, and is exploring expanding institutional custody options and adding a regulated derivatives offering.The company has doubled its U.S. team and aims to triple it by the end of this year. Its executive leadership comes from Coinbase, Barclays, Credit Suisse, and Fidelity.It's working with Silvergate