The opera delta(x) was premiered at the Opera Forward Festival 2022 as part of the OFF LAB PERFORMING ARTS, commissioned by the Nationale Opera & Ballet.

• Composer: Petra Cini
• Director: Toni Kritzer
• Scenography: Merel van de Langkruis
• Libretto 1: Hiske Krammer and Wessel Padberg
• Libretto 2 (mathematical): Petra Cini
• Dramaturgy: Hiske Krammer and Wessel Padberg
• Production: Beer Crolla and Tessel van Ruitenbee