Bashkit

Bashkit is a virtual bash sandbox written in Rust that runs untrusted shell scripts produced by AI agents without spawning a single operating system process. Every command is reimplemented in Rust and executed in memory against a virtual filesystem, so there is no fork, no exec and no way to escape to the host shell. It is built for developers of AI agents, coding tools, editors and evaluation harnesses who want to give a model a bash tool without the overhead or risk of containers. It implements 167 commands, including grep, sed, awk, jq, curl, find, xargs, tar, git and ssh, along with in process Python and TypeScript, and covers a substantial part of the POSIX shell language plus bash extensions such as arrays, brace expansion, extended globs, coprocesses and traps. Filesystems can be purely in memory, overlaid or mounted, and host access exists only where it is explicitly mounted. Resource limits cap commands, loops, output, input and filesystem size to resist runaway or malicious scripts. A BashTool interface provides discovery metadata, streaming output and system prompts for any agent framework, snapshotting serialises shell state and filesystem contents so work can be checkpointed and resumed, and running it with no arguments gives an interactive shell. Packages are available for Rust, Python and TypeScript, and a skill can be installed so coding agents know how to wire it in. Bashkit is free and open source under the MIT licence. The site publishes no pricing and there is no paid tier. It is developed by Everruns, and the Rust crate needs no sidecar process or external runtime dependencies.