New Twitter boss Elon Musk has sent staff a brutal email demanding they go “hardcore” and revel in working long hours, or leave the tech firm.

If staff don’t agree to the onerous new conditions within 48 hours, the company will assume they want to depart and will start redundancy proceedings.

The email is the latest in a series of sweeping changes Musk has made to Twitter in the few weeks since he took control in a $66bn ($72 billion) deal that heavily overvalued the company.

Half the workforce of the San Francisco-based firm has been laid off, senior executives and the board were given the boot, the remaining workers have been told they can no longer work from home, free lunches have been axed and new features have been launched on the site and then swiftly dropped as users enthusiastically abused them.

Musk has also reportedly fired individual staff who have disagreed with him.

Go ‘hardcore’ or go home – permanently

According to former Skype and Uber engineer Gergely Orosz, Musk sent an all-staff email at midnight on Tuesday heralding “Twitter 2.0″.

Elon Musk wants staff to go hard and work long hours or leave. Photo / AP

In the message, Musk wrote: “Going forward, to build a breakthrough Twitter 2.0 and succeed in an increasingly competitive world, we will need to be extremely hard-core”.

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Staff are told bluntly that “only exceptional performance will constitute a passing grade”.

Twitter, it goes on, will be engineering-driven with coders playing a more prominent role in the business.

According to reports, scores of non-engineering roles and entire departments have been axed such as Twitter’s communications unit.

Staff will now be expected to be “working long hours at high intensity”. Musk himself has reportedly slept in his office at times at Tesla.

The email then contained a link that staff were instructed to click on to indicate they agreed to Twitter’s new hard-core, long-hours work environment.

Scores of non-engineering roles and entire departments have been axed such as Twitter’s communications unit. Photo / AP

And there was a warning to those staff who failed to click “yes”.

“Anyone who has not done so by 5 pm will receive three months of severance.

“Whatever decision you make, thank you for your efforts to make Twitter successful,” Musk concluded.

California employment law, like many US states, allows companies to cut staff for almost any reason unless it can be proven that the reason was discriminatory.

In other countries in which Twitter operates that is not the case and it’s unclear if the new diktat can be enforced or if staff can be made redundant simply because they didn’t reply to an email.

Engineer reportedly sacked for disagreeing with Musk

This missive is part of Musk’s imposition of a new working environment at Twitter which some staff are struggling with.

And those tempted to criticise Musk may need to watch out – they reportedly could be sacked.

On the weekend, Musk posted a tweet apologising for the site is “super slow” in some countries which he said was due to “poorly batched RPCs (remote procedure cells)”.

Twitter engineer Eric Frohnhoefer replied to the tweet saying: “I have spent ~6yrs working on Twitter for Android and can say this is wrong.”

Musk then challenged Frohnhoefer to detail to him what he had done “to fix that”.

To which Frohnhoefer gave a detailed rundown of all the work he and his team had done to isolate the issues slowing the site down and that key to the problem was that the app was “bloated with features that get little usage”.

“We should probably prioritise some big rewrites to combat 10+ years of tech debt and make a call on deleting features aggressively,” the staff member concluded.

A day later Musk replied that “he’s fired”.

That tweet was later deleted. However, Frohnhoefer uploaded an image of a locked computer and said “guess it is official now”.

Some Twitter staff appear to be in turmoil given actions they were allowed to do last month are potentially now a sackable offence.

Prior to Musk’s purchase of Twitter, it had been a company that encouraged frank feedback including to management. A code of conduct, ostensibly still in place, allows staff to criticise senior members of staff.

Yet website Platformer has reported several staff have now been fired for criticism of Musk not even publicly but on internal communication channels.

“I would like to apologise for firing these geniuses,” Musk said in a tweet.

“Their immense talent will no doubt be of great use elsewhere.”

- Benedict Brook, news.com.au