# JAX v0.11.0 — JAX v0.11.0

- Product: JAX (https://whatsnew.fyi/product/jax)
- Vendor: Google
- Date: 2026-07-16
- Version: v0.11.0
- Original notes: https://github.com/jax-ml/jax/releases/tag/jax-v0.11.0
- Permalink: https://whatsnew.fyi/product/jax/releases/v0.11.0

What's New is an index, not a publisher: every entry below links to the vendor's own release notes, which are the authoritative source. Entries are labelled where they are hand-curated sample data, pre-releases, or drawn from a secondary source such as a developer blog.

Reuse: the summaries, labels and curation here are © What's New. Quote freely with attribution and a link back; wholesale republication of the corpus is not permitted — terms: https://whatsnew.fyi/terms. The vendors' own release notes remain their publishers'.

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- **added** — Add hijax API documentation and helpers in jax.experimental.hijax for deriving VJPHiPrimitive autodiff rules including linearize_from_jvp, apply_derived_linearization, vjp_fwd_from_jvp, transpose_jvp, vjp_fwd_from_lin, transpose_linearized, and jvp_from_lin
- **added** — Add jax.custom_remat to the top-level jax namespace for per-function control of rematerialization under the new jax_remat3 implementation
- **changed** — Convert jax.checkpoint_policies from a namespace object to a submodule, enabling from jax.checkpoint_policies import ... syntax
- **added** — Expose SaveOnlyTheseNames, SaveAnyNamesButThese, and SaveAndOffloadOnlyTheseNames policy classes in jax.checkpoint_policies
- **added** — Add jax.Inline enum for specifying inlining policies to jax.jit
- **removed** — Remove deprecated jax.cloud_tpu_init module
- **removed** — Drop support for Python 3.11
- **removed** — Drop support for NumPy 2.0
- **removed** — Drop support for SciPy 1.14
- **removed** — Drop support for Python 3.13 free-threaded build
- **changed** — Change jax.numpy.empty and jax.numpy.empty_like to produce uninitialized arrays instead of zero-initialized arrays
- **deprecated** — Deprecate passing 2-dimensional arrays or mixed 2D and 3D arrays to jax.numpy.cross, to be removed in JAX 0.12.0
- **removed** — Remove previously-deprecated APIs from jax.core including CallPrimitive, DebugInfo, DropVar, Effect, Effects, InconclusiveDimensionOperation, JaxprTypeError, abstract_token, check_jaxpr, concrete_or_error, find_top_trace, gensym, get_opaque_trace_state, is_concrete, is_constant_dim, is_constant_shape, jaxprs_in_params, new_jaxpr_eqn, no_effects, nonempty_axis_env_DO_NOT_USE, primal_dtype_to_tangent_dtype, unsafe_am_i_under_a_jit_DO_NOT_USE, unsafe_am_i_under_a_vmap_DO_NOT_USE, unsafe_get_axis_names_DO_NOT_USE, valid_jaxtype, JaxprPpContext, JaxprPpSettings, OutputType, aval_mapping_handlers, call, concretization_function_error, custom_typechecks, literalable_types, no_axis_name, and trace_ctx
- **removed** — Remove previously-deprecated APIs from jax.interpreters.pxla including Index, MeshAxisName, MeshExecutable, global_aval_to_result_handler, global_result_handlers, are_hlo_shardings_equal, is_hlo_sharding_replicated, ArrayMapping, _UNSPECIFIED, array_mapping_to_axis_resources, and op_sharding_to_indices

* New features
  * Added a doc on defining custom derivative rules with the experimental
    hijax API (`hijax-custom-derivatives`), along with
    `jax.experimental.hijax` helpers for deriving `VJPHiPrimitive` autodiff
    rules from a `jvp` or `lin` rule: `linearize_from_jvp` with
    `apply_derived_linearization`, `vjp_fwd_from_jvp` with `transpose_jvp`,
    `vjp_fwd_from_lin` with `transpose_linearized`, and `jvp_from_lin`.
  * Added `jax.custom_remat` to the top-level `jax` namespace, for
    per-function control of rematerialization under the new `jax_remat3`
    implementation.
  * `jax.checkpoint_policies` is now a submodule rather than a namespace
    object (so `from jax.checkpoint_policies import ...` now works; attribute
    access is unchanged), and it additionally exposes the name-based policy
    classes `SaveOnlyTheseNames`, `SaveAnyNamesButThese`, and
    `SaveAndOffloadOnlyTheseNames`.
  * Added `jax.Inline` enum for specify inlining policies to
    `jax.jit`.

* Breaking changes
  * The deprecated module j`ax.cloud_tpu_init` was removed. This did nothing and
    references to it can be safely removed.
  * Support for Python 3.11, NumPy 2.0, and SciPy 1.14 has been dropped, per the
    [deprecation policy](https://docs.jax.dev/en/latest/deprecation.html).
  * Support for Python 3.13 free-threaded (`3.13t`) has been dropped. Python
    3.13 free-threaded was an experimental build needed to bootstrap free
    threading support. Now that Python 3.14t is stable, it is time to drop the
    experimental build. Other parts of the Python ecosystem (e.g.
    `cibuildwheel`, `scipy`) are making similar moves.
  * `jax.numpy.empty` and `jax.numpy.empty_like` now produce
    uninitialized arrays, similar to their NumPy counterparts. Prior to v0.11.0,
    they produced arrays initialized to zeros. To recover the previous behavior,
    use `jax.numpy.zeros` or `jax.numpy.zeros_like` instead.

* Deprecations
  * Passing 2-dimensional arrays (or mixed 2D and 3D arrays) to `jax.numpy.cross` is deprecated and will be removed in JAX 0.12.0, aligning with NumPy 2.5 behavior.
  * Several previously-deprecated APIs from `jax.core` have been removed, including
    `CallPrimitive`, `DebugInfo`, `DropVar`, `Effect`, `Effects`, `InconclusiveDimensionOperation`,
    `JaxprTypeError`, `abstract_token`, `check_jaxpr`, `concrete_or_error`, `find_top_trace`, `gensym`,
    `get_opaque_trace_state`, `is_concrete`, `is_constant_dim`, `is_constant_shape`, `jaxprs_in_params`,
    `new_jaxpr_eqn`, `no_effects`, `nonempty_axis_env_DO_NOT_USE`, `primal_dtype_to_tangent_dtype`,
    `unsafe_am_i_under_a_jit_DO_NOT_USE`, `unsafe_am_i_under_a_vmap_DO_NOT_USE`,
    `unsafe_get_axis_names_DO_NOT_USE`, `valid_jaxtype`, `JaxprPpContext`, `JaxprPpSettings`, `OutputType`,
    `aval_mapping_handlers`, `call`, `concretization_function_error`, `custom_typechecks`,
    `literalable_types`, `no_axis_name`, and `trace_ctx`.
  * Several previously-deprecated APIs from `jax.interpreters.pxla` have been removed, including
    `Index`, `MeshAxisName`, `MeshExecutable`, `global_aval_to_result_handler`, `global_result_handlers`,
    `are_hlo_shardings_equal`, `is_hlo_sharding_replicated`, `ArrayMapping`, `_UNSPECIFIED`,
    `array_mapping_to_axis_resources`, and `op_sharding_to_indices`.