KYIV – He's credited with the Facebook post that sparked the Euromaidan protests that swept former President Viktor Yanukovych from power.
He founded a groundbreaking online TV station and reported on the conflict in the eastern Donbas region on his popular series "Vostok."
And now, as Ukraine prepares for key parliamentary elections, he's trying to win a seat in Ukraine's parliament, the Verkhovna Rada to fight for reform from within.
Mustafa Nayem is one of dozens of Euromaidan activists who are trying to pivot from street politics to the halls of power, where they hope to spearhead reform and turn Ukraine into a prosperous European state.
"The fact is we've been criticizing everything that's happened in the country for the last decade," Nayem told RFE/RL.
"Now we have two choices: either we can continue criticizing or we can now try and actually change things."
And the October 26 legislative elections should be their moment. With Yanukovych's formerly ruling Party of Regions in disarray and not contesting the elections, and with old stalwarts like Yulia Tymoshenko's Fatherland party polling poorly, the door appears open for fresh faces.
The outcome of this key vote will determine whether a new political elite can reform the bloated state bureaucracy and clean up endemic corruption.
Over the eight months since Yanukovych fell from power and fled the country, activists like Nayem, 33, have become increasingly frustrated at the slow pace of reform.
Some are vying for seats in the 450-seat legislature as independents; some are running on various party lists.
"Effectively we will be a lobby inside the Rada," said Nayem, who will be running as a candidate with President Petro Poroshenko's bloc.
Others running on Poroshenko's party list include Serhiy Leshchenko, an investigative journalist for the newspaper "Ukrainskaya pravda" and Olha Bohomolets, the Euromaidan doctor who treated hundreds during the goriest junctures of the winter protests in Kyiv.
Tetyana Chornovol, a journalist who has investigated official corruption and who was savagely beaten near Kyiv late last December, is running on the party list of the "People's Front," which is led by Prime Minister Arseniy Yatsenyuk.
Volodymr Parasyuk, whose rousing speech on February 21 about the scores of protesters shot dead by snipers sounded the death knell of Yanukovych's rule and brought him national fame, is running as an independent candidate in the western city of Lviv.
Different Parties, Same Principles
Nayem is an Afghan who has lived in Ukraine for 24 years and worked as a journalist for publications, including "Kommersant Ukraine" and "Ukrainskaya pravda."
He is often described as the man who sparked the Euromaidan protests.
On November 21, after Yanukovych announced that he was shelving a much-anticipated association agreement with the European Union in favor of closer ties with Russia, Nayem posted a message on Facebook: "Come on guys, let's be serious. If you really want to do something, don't just 'like' this post. Write that you are ready, and we can try to start something."
After a deluge of replies, he called on activists to congregate on Kyiv's "Maidan Nezalezhnosti," or "Independence Square" which soon became the site of a sprawling winter tent encampment and served as the nerve center of the protests.
Nayem went on to co-found and become editor in chief of Hromadske TV, an online station that went live amid the protests and brought together independent career journalists who had been dismissed from positions at outlets beholden to Yanukovych.
Nayem was chosen as one of four activists to represent the "Euromaidan" when it was nominated for this year's Sakharov Prize, the European Union's top human rights award. (The prize was awarded to Congolese physician Denis Mukwege on October 21. The Euromaidan, a finalist for the award, was the runner-up.)
On September 13, he announced plans to run for parliament with Poroshenko's bloc, which is the frontrunner according to most polls.
Asked if the different party affiliations of Euromaidan activists would hamstring their attempts at reform, Nayem said he was optimistic.
"At the moment, it's clear that we are united by the same principles," he said. "We stand for all the work that is done by civil society. In this sense we have our own agenda -- we understand how things should not be and should be. This will unite us."
But Vitaly Bala, a Kyiv-based political analyst, was skeptical that the activists would breathe new life into Rada.
"They don't understand, like the majority of lawmakers currently in the Rada, that politics is a profession," he said. "I don't think people with no experience of politics will be able to change things."