Java Virtual Machine implementation in Rust Features bytecode verifier not-painfully-slow interpreter All language features before Java 7 except for threads I/O operations, including file I/O (only for native platforms) support for some classes in the java.io, java.lang, and java.util packages ability to run Java on the browser through WASM no_std support alloc is still required Upcoming features Implementations for the remaining stack operations More ClassLoader features Windows support Array type verification in verifier Object class verification in verifier Better performance 8-byte Value split fields into object and primitive fields? other? Missing features Proper charset support invokedynamic (Java 8 lambdas) support Multithreading (Thread.start) support Lots of API Better garbage collection A JIT compiler