After his university graduation, Allé startet his professional career as an assistant at the Vienna Observatory in 1856.

[8] In June 1882 Allé was appointed professor of mathematics at the Deutsche Technische Hochschule in Prague.

[9] There, he was also dean for five periods[3] and different faculties[10][11] but declined serving as rector after his election in June 1887 for health reasons.

[12] In 1896 he succeeded Josef Kolbe at the chair of mathematics at the Polytechnic Institute in Vienna, where he served as rector as well in 1900/01.

[3] The early scientific work of Allé led to a number of publications in astronomy where he contributed on orbit determination of planets and comets.