Halvorson’s latest ensemble expands on the Thumbscrew trio of bassist Michael Formanek and drummer Tomas Fujiwara with the addition of trumpeter Adam O’Farrill and vocalist Amirtha Kidambi. Named for a phrase uttered by Halvorson’s mentor Anthony Braxton, Code Girl represents Halvorson’s songwriter side, with several pieces featuring her lyrics. An artist whose range of experience includes both Hindi devotional music and free jazz improvisation, Kidambi brings a surefooted power and intimacy to the music, matched by the freewheeling trumpet of O’Farrill, whose fluency presents new harmonic and melodic possibilities. The band, with trumpeter Ambrose Akinmusire in place of O’Farrill, recently released their self-titled debut double-album on Firehouse 12 Records.