Boris Nikolayevich Yeltsin (Russian: Boris Nikolaevich El'tsin, IPA: [ba'rjis njIka'laIvjItc 'jeljtsin] ( listen); 1 February 1931 - 23 April 2007) was a Soviet and Russian politician and the first President of the Russian Federation, serving from 1991 to 1999. Originally a supporter of Mikhail Gorbachev, Yeltsin emerged under the perestroika reforms as one of Gorbachev's most powerful political opponents. During the late 1980s, Yeltsin had been a candidate member of the Politburo, and in late 1987 tendered a letter of resignation in protest. No one had resigned from the Politburo before.

Boris Yeltsin was born in the village of Butka, Talitsky District, Sverdlovsk, USSR, on 1 February 1931. In 1932 after the state took away the entire harvest from the recently collectivised Butka peasants, the Yeltsin family moved as far away as they could, to Kazan, more than 1,100 kilometres from Butka, where Boris' father, Nikolai, found work on a construction site. Growing up in rural Sverdlovsk, he studied at the Ural State Technical University (now Urals Polytechnic Institute), and began his career in the construction industry. In 1934 Nikolai Yeltsin was convicted of anti-Soviet agitation and sentenced to hard labour in a gulag for three years. Following his release in 1936 after serving two years, Nikolai took his family to live in Berezniki in Perm Krai, where his brother Ivan, a blacksmith, had been exiled the year before for failing to deliver his grain quota. Nikolai remained unemployed for a period of time and then worked again in construction. His mother, Klavdiya Vasilyevna Yeltsina, worked as a seamstress. Boris studied at Pushkin High School in Berezniki. He was fond of sports (in particular skiing, gymnastics, volleyball, track and field, boxing and wrestling) despite losing the thumb and index finger of his left hand when he and some friends furtively entered a Red Army supply depot, stole several grenades, and tried to disassemble them. In 1949 he was admitted to the Ural Polytechnic Institute in Sverdlovsk, majoring in construction, and he graduated in 1955. The subject of his degree paper was "Construction of a Mine Shaft". From 1955 to 1957 he worked as a foreman with the building trust Uraltyazhtrubstroy. From 1957 to 1963 he worked in Sverdlovsk, and was promoted from construction site superintendent to chief of the Construction Directorate with the Yuzhgorstroy Trust. In 1963 he became chief engineer, and in 1965 head of the Sverdlovsk House-Building Combine, responsible for sewerage and technical plumbing. He joined the ranks of the CPSU nomenklatura in 1968 when he was appointed head of construction with the Sverdlovsk Regional Party Committee. In 1975 he became secretary of the regional committee in charge of the region's industrial development. In 1976 the Politburo of the CPSU promoted him to the post of the first secretary of the CPSU Committee of Sverdlovsk Oblast (effectively he became the head of one of the most important industrial regions in the USSR); he remained in this position until 1985.

Using a quote from the above article, answer the following question: What did his parents do?
Boris' father, Nikolai, found work on a construction site.