The Filecoin VM (v4) reference implementation is a Rust-based project providing the necessary framework to integrate the Filecoin Virtual Machine into different blockchain clients, whether through FFI for non-Rust clients like Lotus and Fuhon, or directly for Rust clients such as Forest. This repository includes Go FFI bindings, welcoming contributions for bindings in other languages. Its structure comprises several components including the core FVM engine, a reference SDK for writing Filecoin actors, shared primitives, and IPLD libraries. Testing and benchmarking tools are provided to ensure conformance and performance validation. Versioning is meticulous, supporting major changes, API updates, and backward compatibility, reflecting network upgrade support up to version 21+. Dual-licensed under MIT and Apache-2.0, the project encourages community involvement in enhancing the SDK and expanding language support for WASM-compilable platforms.