It is mostly Python, both the monolith and SoA. A few services are Java, e.g. for talking to Lucene. The github site actually gives a reasonably complete view o

It is mostly Python, both the monolith and SoA. A few services are Java, e.g. for talking to Lucene. The github site actually gives a reasonably complete view of the stack via the various tools we have for integrating with various parts of the stack. https://yelp.github.io/ https://yelp.github.io/