Single-user Nix (flakes enabled), direnv and nix-direnv, wired so that the workspace .envrc is loaded automatically: a direnv hook for interactive bash, and a BASH_ENV / CLAUDE_ENV_FILE hook so agent command shells get the same environment. nix-direnv state lives in the sandbox, not in the host-shared .direnv directory.
| Name | Required | Default | Description |
|---|---|---|---|
autoAllow | Optional | true | Trust every .envrc under the sandbox workspace (direnv whitelist), so no `direnv allow` is needed. Set to "false" to approve .envrc files by hand. Options: true, false |
nixpkgsRef | Optional | nixos-26.05 | nixpkgs branch, tag or commit that nix, direnv and nix-direnv are built from (github:NixOS/nixpkgs/<ref>). Only affects the installed tools, not the project's flake inputs. |
prewarm | Optional | true | On every sandbox start, evaluate the workspace .envrc in the background so the first agent command does not wait for the flake to build. Options: true, false |
| Type | Required | Description | |
|---|---|---|---|
com.docker.sandbox/network-policy@1 | Required | — | |
com.docker.sandbox/lifecycle@1 | Required | — | |
com.docker.sandbox/agent-context@1 | Optional | — | |
com.docker.sandbox/agent-context@2 | Optional | — | |
sbx run <agent> --kit matthisk/nix-direnv-kit:0.1.0Run the following command to install sbx on your machine.
brew install docker/tap/sbxwinget install Docker.sbx