The paper presents new approaches in South Slavic dialectology as applied to the Torlak dialect in Eastern Serbia and Western Bulgaria which belongs genetically to the West South Slavic linguistic continuum, but from the structural point of view is a part of the Balkan Sprachbund. The contested by Serbs and Bulgarians historically homogenous dialect since 1833 is divided by a state border, which is in our times a linguistic border between Serbia and Bulgaria as well. The Torlak is now an endangered vernacular.
The paper is based empiricaly upon the high quality new raw data from the current field research in the geographic areas of Timok and Lužnica, Belogradčik and Tran. The combination of qualitative and quantitative approaches to the micro- and macrolevel of research, i. e. of conventional linguistic methods (dialectology, areal typology and ethnolinguistics) with language technology (quantitative linguistics, geographic information sciences), allows to achieve some heuristically important new results:

• creation of statistically relevant linguistic profiles of dialect speakers in Serbia and Bulgaria;
• dialectometric clustering and visualization of linguistic borders between Serbia and Bulgaria;
• estimating and qualifying the linguistic divergence between the Serbian and Bulgarian part of the Torlak speaking community.

Videorecordings, transcribed texts, graphs with linguistic profiles, digital dialectologic maps and tables will be presented.

References
Ćirković, S. (Ur.). Timok. Terenska istraživanja 2015–2017. Knjaževac, 2018.
Konior D. V., Makarova A. L., Sobolev A. N. Statisticheskii metod iazykovogo profilirovaniia // Vestnik TGU. 2019. № 58. P. 17–33.
Sobolev A. N. Sprachatlas Ostserbiens und Westbulgariens. Marburg: Biblion Verlag, 1998.