Software development is one of the leading sectors of the economy, and it is changing rapidly. To understand where different digital competencies are concentrated, a group of scientists analyzed the digital traces of millions of programmers from 976 cities over 2010-2022. The work was published on the arXiv preprint server (a preprint is a scientific article that has not yet undergone full peer review in a journal).
The study is based on data from Stack Overflow, an online question-and-answer platform where programmers advise one another. Using the location listed in profiles, the specialists determined which skills predominate in each city compared with the global average. A check against job vacancies showed that the resulting picture predicts which skill sets companies seek and how much they pay for them. This indicates that the method reflects the real labor market, not only the characteristics of the platform's users.
It turned out that, despite the global nature of the industry, software competencies are distributed unevenly around the world. For example, London is one of the largest development centers, but skills in artificial intelligence (AI) and iOS are represented there more strongly than in other cities. The scientists explain this as follows: people master skills that are close to those they already have. A city that started with making shirts then moves on to trousers, and then to sewing aircraft seats. A similar logic operates in the software industry.
Of 35 new skills, such as blockchain (a distributed transaction ledger) or deep learning (a machine-learning method using multilayer neural networks), almost two-thirds first appeared in just four cities: London, San Jose (Silicon Valley), New York and Seattle. They then spread to places where related competencies already existed.
European cities generally lag behind the United States and China, but in a number of highly paid skills they remain competitive. Dutch and Scandinavian cities rival the world leaders in cloud computing (working with programs and data on remote servers). Cities in Germany and France with prestigious technical universities are strong in data science, Scandinavian and German regions in gaming technology, and the southern and eastern European countries that joined the EU after 2004 in front-end development (creating the user-visible part of websites and applications).
The scientists also rated the market value of each skill on a scale from 1 to 100 based on approximate salaries in the U.S. market. The most valuable are iOS and Android skills, as well as AI and DevOps (an approach in which software development and operations are carried out jointly). A high concentration of such competencies was noted in some Chinese cities, and in Europe in Munich, London, Paris and Karlsruhe.
The authors emphasize that the method is not a complete census of programmers but merely provides a window into the distribution of skills. Since 2022, large language models have changed the work of developers, so some skills, especially in machine learning and AI, have been noticeably transformed. However, because development experience accumulates over years, the specialization of cities changes slowly, and the patterns obtained, according to the researchers, remain useful for understanding current and near-term prospects. The team is now analyzing GitHub data to obtain a more complete picture.