Miller announced via his Twitter account on Friday that he starts working at the Twitter security team on Monday.
"Looking forward to working with a great team there," he wrote. His new job title will be Software Engineer, Systems.
The company is said to have been interested in hiring Miller for full-time security assistance since last winter, according to Forbes. It speculated that he will be a "highly-skilled intrusion artist" attempting to discover holes in Twitter's security.
Miller's hire at Twitter is noteworthy to Apple users, as he has helped to expose a number of vulnerabilities in Apple. In 2009, he made headlines when after winning the Pwn2Own hacking contest, he declared that Apple's Mac platform is safer than Microsoft's Windows.
Charlie Miller, via his Twitter account.
At the same competition in 2011, he exposed a flaw in the Safari Web browser in Apple's iOS platform. The vulnerability information was provided directly to Apple so that the issue could be patched and addressed before it became public.
Recently, Miller has also been working to crack Google's Android mobile operating system. At this summer's Black Hat conference, he demonstrated security flaws in the near-field communication payment system found in a number of Android smartphones, including Google's Nexus S and Samsung's Galaxy S.
Miller was asked Friday via Twitter if Apple ever showed interest in hiring him. He revealed that the iPhone maker "never even floated the idea much less made me an offer I couldn't refuse."