Since 2015 Aleksei Rubin has been an assistant of Yuri Simonov – chief conductor of the Moscow Philharmonic Orchestra. Since 2018 he has collaborated with the Russian National Youth Symphony Orchestra. With the orchestra Aleksei was a resident conductor during the Denis Matsuev festival in Perm (2019). He also assisted Valery Gergiev, Mikhail Jurowski, Daniele Gatti and Leonard Slatkin.
Aleksei regularly appears as a guest conductor with the Rostov–on–Don Academic Symphony Orchestra, the Moldova Philharmonic Orchestra, Siberian State Symphony Orchestra, Surgut Symphony Orchestra, Ulyanovsk Symphony Orchestra, Saint-Petersburg Youth Symphony Orchestra, Saratov Opera and Ballet Theater. 
He is planning his debut in the season 2020/21 with the State Symphony Orchertra Novaya Rossiya, Ural Youth Symphony Orchestra, Symphony Orchestra of Belgorod State Philharmonic.