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Wasmer

A runtime for running apps and AI agents in lightweight, sandboxed WebAssembly environments.

Stars
21.2k
Forks
1k
Licence
MIT
Language
Rust
Last update
4 days ago
Type
Dev tool

What it is

Wasmer runs programs inside sandboxes, isolated environments where you decide which files, network access and environment variables the program can use. It is built on WebAssembly, so the same packaged software can run on macOS, Linux and Windows, locally, in the cloud, or in a browser. Developers use it to run tools like Python or Bash safely, or to embed sandboxes inside their own applications through the Wasmer SDK.

  • Run a Python script in a sandbox with `wasmer run python/python`
  • Execute code from an AI agent inside an isolated sandbox using the SDK
  • Run a shell command or a packaged tool like FFmpeg or SQLite without installing it on the host
  • Embed a sandbox in a JavaScript, Python, Swift or Rust application

Great for

  • Developers who want to run untrusted or third-party code with explicit access controls
  • Teams embedding isolated code execution into their own apps via the SDK
  • People who want to try Python, Bash or other packaged software without installing it locally
  • Builders of AI agents who need a contained place for an agent to run code

Not ideal for

  • Users who need a finished end-user application; this is a runtime and sandbox platform, not a consumer app
  • Projects that need a mature, stable SDK today, since the README says the SDK is currently alpha
  • Anyone needing full native performance or OS-level features, since the README does not describe those and programs must run inside the sandbox
Step-by-step guide: how to use WasmerInstall, first run, examples, tips and FAQs

How to get it

  1. 1

    Install with a package manager

    You'll need: macOS or Linux shell (or PowerShell on Windows) · Node.js 20 or newer for the JavaScript SDK (optional)

    Install the CLI on macOS or Linux

    curl https://get.wasmer.io -sSfL | sh

    Install via Homebrew

    brew install wasmer

    Install the JavaScript SDK

    npm install @wasmer/sdk
  2. 2

    Run it

    • Install the CLI using the curl command or Homebrew
    • Run Python in a sandbox with: wasmer run python/python -- -c "print('Hello from Wasmer')"
    • Try a shell command with: wasmer run wasmer/bash -- -c "echo 'Hello from Wasmer'"
    • Optionally try the browser version at wasmer.sh without installing anything
  3. 3

    Get the most out of it

    • Use --volume to grant the sandbox access to a specific local directory
    • Use --net only when your program needs host networking
    • Install the JavaScript, Python or Swift SDK to embed sandboxes in your own application
    • Explore packages on the registry at wasmer.io/explore, such as PostgreSQL via wasmer/pglite

Downloads

Strengths

  • Sandboxes give explicit control over file, network and environment access by default
  • Packages from the registry can be run with a single command
  • Multiple language SDKs (JavaScript, Python, Swift, Rust) with the same core idea

Trade-offs

  • The README labels the SDK as alpha, so APIs may change
  • The Rust SDK is currently a source dependency and crates.io publishing is disabled
  • The README does not detail performance benchmarks, so claims of being fast rest on the project's own description

How it compares

ProjectStarsTypeLevelUpdatedBest for
wasmer (this)21.2kDev toolintermediate4 days agoDevelopers who want to run untrusted or third-party code with explicit access controls
PowerShell56kCLIbeginner4 days agoDevelopers who script or automate tasks across Windows, Linux, and macOS
chezmoi22.1kDev toolintermediate4 days agoPeople who use more than one computer and want their settings to match
quickemu16.6kDev toolbeginner7 days agoPeople who want to try a Linux distribution without manual QEMU configuration
inshellisense10.8kDev toolbeginner7 days agoDevelopers who spend a lot of time in the terminal and want suggestions for unfamiliar command options
marktext63.5kAppbeginner4 days agoPeople who write notes or articles in Markdown and want a clean, minimal editor

Stats synced from GitHub. The assessment above was drafted with AI from the project's README on 2026-10-29 and may miss recent changes — check the README before relying on a command. MIT licence: free to use, modify and distribute, including commercially, as long as you keep the copyright notice.