Editor's take: Google has long moved away from its "don't be evil" motto, instead deepening its involvement with US defense-related initiatives. The company is reportedly providing expanded access to its AI services for the Department of Defense, including programs associated with Secretary of Defense Pete Hegseth. The shift has reportedly prompted some longtime engineers with ethical objections to leave the company.

René Mayrhofer, a principal software engineer for Android Security and self-described pacifist and privacy advocate, has resigned from Google. The engineer had worked at Mountain View since 2017 but said he had become increasingly dissatisfied with what he sees as the company's departure from its previously stated – and repeatedly reaffirmed – moral principles.

In a personal farewell note sent to colleagues and obtained by Business Insider, Mayrhofer said he felt he had no choice but to leave, arguing that Google had completely lost its moral compass. The note, sent on May 18, also criticizes the company's leadership over its decision to move away from carbon-neutral goals, citing the high energy demands required to run Gemini's AI models.

Even worse, the letter continues, "the current Google management is now signing deals with the US Ministry of War - where 'any lawful purpose' by the current US government has already been repeatedly demonstrated to be in violation of international laws."

Mayrhofer has since confirmed the authenticity of the letter, saying he no longer feels able to work for a company involved in military AI applications. He added that there are still "very good" people at Google, but argued that their influence has become increasingly marginal compared to the company's overall direction.

Google debuted on Wall Street in 2004, promoting its now-famous "Don't be evil" motto as part of its outsider image in the tech industry. The phrase was later incorporated into the company's code of conduct, where it remained – at least in some form – until 2018. Today, the Alphabet-owned company is increasingly involved in AI applications with military use cases and is working with the Pentagon on classified projects.

Google's evolving stance has proven controversial, with some employees expressing opposition to its defense-related contracts. Mayrhofer noted that Google offered him a job in 2017, but said the company has changed significantly since then. He argued that executive leadership is now approving military-related deals with limited internal discussion or communication.

"I am a pacifist, and have long ago decided that I will not personally work for militaries engaging in offensive warfare," Mayrhofer said in his letter. Google's willingness to "proactively harm people is not something that I can or will be involved with."

The engineer said that, unlike many of his colleagues, he is not financially dependent on Google. In addition to his work on Android, Mayrhofer is also a professor at Johannes Kepler University in Austria. He said he has previously been able to contribute to Android security while maintaining his academic position in the European Union. Now, however, he fears that some of Google's AI products could be used for mass surveillance, including against European citizens.

"I am quite sad that it had to come to this, and desperately hope Google management re-discovers its moral compass," Mayrhofer's said in his letter.