Work on Duolingo’s next big app, Duolingo Music, is well on its way, according to new findings. Recent development efforts indicate the company’s upcoming app will focus on piano, drums, and sheet music lessons, as the edtech company works to again expand its product lineup beyond its flagship language learning app.

The new development work was discovered by iOS developer and reverse engineer Steve Moser, who found images and code hidden inside Duolingo’s mobile apps that included images of piano keys and a drum, the branding “Duolingo Music” and various lines of code referencing music sessions, songs, and music unit reviews, among other things.

The discovery follows a March 2023 Duolingo job listing for a learning scientist who is an “expert in music education who combines both theoretical knowledge of relevant learning science research and hands-on teaching experience,” the listing explained. The listings were the first suggestions that Duolingo would begin working on a music app that would teach concepts in music theory using popular songs. However, Duolingo didn’t officially confirm its plans at the time.

Reached for comment on the new references to music now found in its existing apps, a spokesperson only replied that “Duolingo is constantly experimenting with new features. We have no further details to share at this time,” they added.

However, they reminded TechCrunch that there would be more announcements and news to come at the company’s Duocon event on October 11th. It could be Duolingo is holding any confirmation of its plans around the music app until the event.

This isn’t Duolingo’s first expansion beyond language learning, however.