While research on the marginalization of Latinx teachers has increased, a paucity of research has documented the powerful ways that Latinx teachers resist, challenge, and transform. Informed by the conceptual tools of conformist and transformative resistance, this life history study chronicles the experiences of a Latina in-service science teacher who practices multiple forms of resistance against the persistent and systematic challenges she faces during her educational and professional life. Analysis of interviews and written documents leads to a deeper understanding that teachers' resistant identities are not constructed merely because of their backgrounds, but instead evolve across multiple contexts over time.