Cranelift was originally started as a project to make a new backend for wasm in SpiderMonkey. It took on a life of its own, and has been transferred by the Bytecode Alliance (which Mozilla is a part of). At the moment it's not mature enough for us to use in production (both in terms of performance and in terms of code churn). We're hopeful that will change over the next few years, but we need to ship wasm support now, so we're sticking with our existing backend.
(We intend to keep Cranelift working behind a compile-time flag.)
Cranelift was originally started as a project to make a new backend for wasm in SpiderMonkey. It took on a life of its own, and has been transferred by the Bytecode Alliance (which Mozilla is a part of). At the moment it's not mature enough for us to use in production (both in terms of performance and in terms of code churn). We're hopeful that will change over the next few years, but we need to ship wasm support now, so we're sticking with our existing backend.
(We intend to keep Cranelift working behind a compile-time flag.)