[1] He represented the electoral district of Swan River as a member of the Manitoba New Democratic Party caucus.
Kostyshyn was appointed Minister of Agriculture, Food and Rural Initiatives on January 13, 2012 under Premier Greg Selinger.
He subsequently won re-election to the legislature in the 2023 Manitoba general election in the district of Dauphin.
[3] Born and raised in rural Manitoba, Kostyshyn graduated from Ethelbert High School in 1974, where his children also attended.
For the past 26 years, Kostyshyn has worked on the family farm consisting of a 200 cow/calf operation with 2560 acres.