[3] Koshulynsky actively supported the 2013-2014 demonstrations against the regime of president Viktor Yanukovych and was one of a handful of parliamentary opposition members who remained with the protesters during the police gunfire in February 2014.

[5][6] On 25 October 2015 he unsuccessfully ran for Lviv city mayor, losing in the second round to the incumbent Andriy Sadovyi with 36.8% of the vote.

He believes that Ukraine's government can finance the armed forces by levying increased war tax on the oligarchs.

[10] In the 2019 Ukrainian parliamentary election Koshulynskyi was placed fifth on the joined list of Svoboda with National Corps, the Governmental Initiative of Yarosh and Right Sector.

[18] The Grand Chamber of the Supreme Court annulled this decision on 5 June 2021 and ten days later Virastyuk took the oath of People's Deputy of Ukraine.

[19][20] During Ukraine's 2015 mobilization effort Koshulynskyi joined the artillery troops of the Ukrainian Ground Forces as Gun Commander.

[21] After undergoing training at the International Peacekeeping and Security Centre in Yavoriv, he was deployed to the war zone in the Luhansk region of east Ukraine.