what was his work there?
Professional music conductor.
Gustav Mahler
From June to August 1880, Mahler took his first professional conducting job, in a small wooden theatre in the spa town of Bad Hall, south of Linz. 
what is referred as symphony no. 8 (mahler)? The Symphony No. 8 in E-flat, is one of the largest-scale choral works in the classical concert repertoire. who is its composer? Gustav Mahler. when? In the summer of 1906. where was it premiered? Munich. and then performed? Amsterdam, Prague and Vienna. where was the composer first appointed? In a small wooden theatre in the spa town of Bad Hall, south of Linz.
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Gustav Mahler [SEP] First appointments
From June to August 1880, Mahler took his first professional conducting job, in a small wooden theatre in the spa town of Bad Hall, south of Linz. The repertory was exclusively operetta; it was, in Carr's words "a dismal little job," which Mahler accepted only after Julius Epstein told him he would soon work his way up. In 1881, he was engaged for six months (September to April) at the Landestheater in Laibach (now Ljubljana, in Slovenia), where the small but resourceful company was prepared to attempt more ambitious works. Here, Mahler conducted his first full-scale opera, Verdi's "Il trovatore", one of 10 operas and a number of operettas that he presented during his time in Laibach.