bytecodealliance/wasmtime v36.0.0

on GitHub

36.0.0

Released 2025-08-20.

Added

• Cranelift's has initial support for inlining between functions. Wasmtime
  additionally now has support for inlining as well, for example between modules
  in a component.
  #11210
  #11239
  #11228
  #11269
  #11283

• The async proposal for the Component Model is now fully implemented in
  Wasmtime with a number of WASIp3 interfaces implemented. The implementation
  is still off-by-default and the implementation of WASIp3 is not fully
  complete, but is remains suitable for testing.
  #11127
  #11136
  #11137
  #11238
  #11221
  #11250
  #11257
  #11291
  #11325

Changed

• Users who implemented WasiHttpView::is_forbidden_header from
  wasmtime-wasi-http now need to include DEFAULT_FORBIDDEN_HEADERS, e.g.
  DEFAULT_FORBIDDEN_HEADERS.contains(name) || name.as_str() == "custom-forbidden-header"
  #11292

• Cranelift's incremental cache has received some optimizations.
  #11186

• Wasmtime's internal implementations of WebAssembly primitives has been
  refactored to be modeled with safer internal primitives.
  #11211
  #11212
  #11216
  #11229
  #11215
  #11254
  #11255
  #11319
  #11320

• Detection of native hardware features has been refactored on s390x.
  #11220

• Further progress has been made towards an implementation of the WebAssembly
  exceptions proposal, although it is not yet complete.
  #11230
  #11321

• Cranelift's assembler for x64 now supports EVEX encoding.
  #11153
  #11270
  #11303

• The default implementation of send_request in the wasmtime-wasi-http crate
  is now behind an on-by-default feature gate.
  #11323

• Configuration of the bindgen! macro has been redesigned to more consistently
  configure per-function options such as whether or not it's async.
  #11328

• Initial support fo mutatis has been added to Wasmtime's fuzzers.
  #11290

• The debug-builtins crate feature of wasmtime no compiles on no_std
  targets.
  #11304

Fixed

• Deserializing external modules no long unnecessarily requires the allocation
  to be aligned.
  #11306

• A CMake linker error and warning when using the C API on macOS has been fixed.
  #11293
  #11315

• The C API declaration of wasmtime_component_linker_instance_add_func has
  been fixed.
  #11327

• The calculation of reachable DWARF has been fixed.
  #11338