 He also began to perform stand-alone concerts and his reputation soon spread, for in 1791 he was appointed conductor of the opera, Prague, and he officiated there for many years, during which time several of his own works met with success.It was while he was conductor of the Prague opera that he first met and became intimately associated with Mozart.He was a friend of the great composer during his residence in Prague, and at the first performance of "Don Giovanni", October 29, 1787, Kucharz played the mandolin in the orchestra, accompanying the serenade "Deli Vieni", while Mozart conducted.