Twitter’s Chief Technology Officer Adam Messinger said in a tweet on Tuesday he would be leaving the company, the latest in a string of high-profile executive departures since founder Jack Dorsey returned as permanent CEO last year.
Messinger has been working with Twitter for five years and became the CTO in March 2013.
As chief technology officer, Messinger was responsible for engineering, product development, and design at the microblogging company, which faces stagnating user growth amid stiff competition from rivals.
Prior to joining Twitter in 2011, he was vice president of development at Oracle Corp.
Twitter’s Chief Operating Officer Adam Bain left the company last month, handing over the reins to Chief Financial Officer Anthony Noto.
Josh McFarland, vice president of product at Twitter, also said on Tuesday that he would leave the company to join Silicon Valley venture firm Greylock Partners.
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Twitter said in October it would lay off 9% of its employees and shut down video app Vine to keep its costs down.
The company did not immediately respond to a request for comment.