In 1821, he entered the service of Count Franz Anton von Magnis (1786–1861), owner of an estate in Strážnice, where he would manage the reconstruction of historic buildings.
His first assignment, however, involved building an access road to an extension of the Count's park; on the opposite side of a river.
Schnirch proposed what was then a technical novelty: a chain bridge, none of which had yet been built in that part of Europe.
After 1861, he was Chief Inspector for railway structures; in which position he also helped plan a rail line from Olomouc to Prague.
In the use of chain bridges, some design defects emerged in later years: the underestimation of the traffic load, and the insufficient consideration of lateral wind forces, which led to the demolition or reconstruction of numerous bridges, including some by Schnirch.