Keith Alexander, a retired Army general and former high-ranking national security leader, was elected to Amazon’s board of directors on Wednesday.

Alexander served four years as commander of the U.S. Cyber Command ending in 2014. He was also director of the National Security Agency and chief of the Central Security Service from 2005 to 2014, Amazon said. That year, he founded technology company IronNet Cybersecurity, which he still leads.

Alexander joins 10 other directors on Amazon’s board. He was appointed to serve on the board’s audit committee.   

The appointment of a high-ranking veteran and national security leader comes as Amazon continues to dispute the Defense Department’s award of a $10 billion military cloud computing contract to rival Microsoft.