JAX 0.12.0 adds a proxy backend and removes jax.custom_remat

The JAX project published JAX v0.12.0 on GitHub on October 19, 2026. The release notes list new features including jax.lax.polynomial for polynomial evaluation, jax.custom_vjp.defremat for customizing rematerialization, a registered proxy backend that connects to an IFRT Proxy server such as Pathways on Cloud, jax.sharding.no_collectives, and support for DLPack 1.0. Breaking changes listed include the removal of jax.custom_remat in favor of jax.custom_vjp.defremat, a requirement on x86-64 for an Intel Haswell or newer CPU with AVX2 and FMA support, and a minimum of NumPy 2.2. USASI has not tested this release.1

USASI. (2026, October 21). JAX 0.12.0 adds a proxy backend and removes jax.custom_remat. United States of America Superintelligence. https://unitedstatesofamericasuperintelligence.com/news/jax-0-12-0-released/

@misc{usasi_news_jax_0_12_0_released,
  author = {{USASI}},
  title = {JAX 0.12.0 adds a proxy backend and removes jax.custom\_remat},
  year = {2026},
  month = oct,
  howpublished = {\url{https://unitedstatesofamericasuperintelligence.com/news/jax-0-12-0-released/}},
  note = {United States of America Superintelligence. Last updated 2026-10-21}
}