Open Source Rust Runtimes

A standalone runtime for WebAssembly The Wasmtime CLI can be installed on Linux and macOS (locally) with a small install script.

RunMat is a free, open-source, MATLAB-compatible runtime designed to execute existing MATLAB/Octave code without license fees or vendor lock-in. The project emphasizes modern performance, describing a V8-inspired runtime architecture with a lightweight installer for Linux, macOS, and Windows. It targets full language grammar and core semantics, aiming to support arrays, indexing idioms, multiple return values, and classdef constructs that many scientific users rely on. The distribution includes one-line install scripts and highlights forthcoming editor integrations (VS Code and IntelliJ plugins) to provide syntax highlighting, IntelliSense, and integrated debugging. Its website positions RunMat as a drop-in engine for current codebases, with an OSS development model inviting contributors to inspect the code or build from source. Overall, the goal is to give researchers, students, and engineers a fast, portable runtime for numerical computing workloads.

OpenShell is an open-source runtime designed to safely run autonomous AI agents in isolated environments. Developed by NVIDIA, it provides sandboxed execution spaces that protect system resources, credentials, and data from unauthorized access. Each agent runs inside a containerized sandbox governed by declarative YAML security policies that control network access, file permissions, and process behavior. The platform includes a gateway service that manages sandbox lifecycles and routes AI inference requests through controlled providers. OpenShell also features a privacy-aware routing system that prevents sensitive information from leaving the sandbox environment. By combining container isolation, policy enforcement, and agent orchestration, OpenShell offers a secure infrastructure for developing and operating AI agents.

Mise (formerly RTX) is a cross-language CLI tool and task runner that manages developer tools, environment variables, and project tasks in a unified configuration (mise.toml). It handles tool installation (e.g., Node, Python, Terraform), env var profiles, and repeatable command scripting.

This is an experimental Javascript lexer, parser and interpreter written in Rust. Currently, it has support for some of the language.

Iced is a cross-platform, end-user-oriented GUI library for Rust, inspired by The Elm Architecture. It expects you to split user interfaces into four different concepts, which are: the state of your app; messages, which are user interactions or other meaningful events; view logic, which displays your state as widgets that can result in messages; and update logic, which offers a way to update your state and react to messages. Iced is very simple and easy to use, and is type-safe. It offers many great features including built-in widgets and custom widget support, debug overlay, a modular ecosystem and more.

Build reliable network applications without compromising speed, with Tokio! Tokio is an event-driven, non-blocking I/O platform and asynchronous runtime for the Rust programming language that allows you to write reliable and slim network applications. At a high level, Tokio provides a number of components needed for building asynchronous applications. These include a multithreaded, work-stealing based task scheduler; a reactor that's supported by the operating system's event queue; and asynchronous TCP and UDP sockets. Tokio is reliable in that its APIs are memory-safe, thread-safe, and misuse-resistant. Thanks to its task scheduler, it is also incredibly fast. It is capable of processing hundreds of thousands of requests per second with little to no overhead.

Aurae is on a mission to be the most loved and effective way of managing workloads on a node. Our hope is that by bringing a better set of controls to a node, we can unlock brilliant higher-order distributed systems in the future. Aurae deploys a memory-safe 1 runtime daemon, process manager, and PID-1 initialization system to remotely schedule processes, containers, and virtual machines as well as set node configurations (e.g., networking storage). Through system proportioning and enterprise workload isolation techniques, the Aurae open-source project can complement higher-order schedulers and control planes (such as Kubernetes) as Aurae supports the usage of multi-tenant workloads and enterprise identities all the way down to the socket layer.

Lunatic is a universal runtime for fast, robust and scalable server-side applications. It's inspired by Erlang and can be used from any language that compiles to WebAssembly.

Create apps that run everywhere, publish, share with the community, and deploy to the edge, globally. Serve sandboxed WebAssembly apps anywhere through a single runtime and do in days what others do in months. Using a binary for each platform and chip is the past. Rise above with lightweight containerized apps that simply run everywhere. Supports almost every programming language. Truly universal, runs everywhere & fast as native. Packages are limited by their languages no more. Collaborate across stacks, leverage the ecosystem, and contribute your own packages. Get the scalability of serverless and the reusability of the cloud. Deploy to the edge, save your users time and yourself money. Faster, affordable & indefinitely scalable. All languages are fully containerized & collaborative. Plug your own backend, compiler, or runner. Run apps at close to native speed and outperform the competition.