Praia Labs Docker Sandbox Kits

This repository contains custom Docker Sandbox Kits developed by Praia Labs (GitHub).

Warning

Experimental Feature & Active Development: Docker Sandboxes (sbx) and Kits are experimental features under active development. Syntax, CLI commands, and features may change regularly.

Overview

Docker Sandbox Kits are declarative configurations used to customize and extend AI agent sandbox environments. This repository serves as a collection of custom kits tailored for various agent workflows.

To learn more about Docker Sandboxes and Kits, refer to the following official resources:

• Docker Sandboxes Documentation
• Docker Sandbox Custom Kits Guide
• Official Contrib Repository (docker/sbx-kits-contrib)

Usage

You can run sandboxes with these custom kits either by referencing the local directory path or directly via the remote Git repository URL.

Local Development / Usage

If you have cloned this repository locally, you can spin up a sandbox with a specific kit using:

sbx run agents/<kit-dir>

For example, to run the agy (Google Antigravity CLI) kit:

sbx run agents/agy

Remote Git Reference

Docker Sandbox supports fetching kits directly from remote Git repositories. You can reference kits in this repository using the following syntax pattern:

Important

As of sbx v0.34.0, you need to explicitly allow the kit source before using it:

sbx settings set kit.allowedSources '["docker.io/","github.com/praialabs/"]'

sbx run 'git+https://github.com/praialabs/sbx-kits.git#dir=agents/<kit-dir>'

Example (composing the agy agent kit with the default-allow-policies mixin kit):

sbx run 'git+https://github.com/praialabs/sbx-kits.git#dir=agents/agy' \
  --kit 'git+https://github.com/praialabs/sbx-kits.git#dir=mixins/default-allow-policies'

For more details on Git remote references, see the Docker Sandboxes Git Repository Documentation.

Custom Template

This repository provides a custom sandbox template tailored for Elixir development with the Google Antigravity CLI (agy).

The agy-elixir/Dockerfile extends docker/sandbox-templates:shell-docker and pre-bakes the Elixir runtime environment, the Antigravity CLI, and additional tooling into the image to avoid repetitive installation steps.

Formal Verification with Lean 4

The template also bundles the Lean 4 theorem prover to enable formal verification workflows directly alongside Elixir codebases. Paired with the bundled elixir-lean-formalization skill in the agy agent, agents can formalize Elixir modules to mathematically verify state invariants, prove equivalence for refactorings, and catch subtle edge-case bugs.

Building the Template Locally

We manage building the template image using Docker Bake, which ships with Docker and automatically handles building the image using a declarative file:

docker buildx bake

You can use environment variables to override specific tool versions during the build process:

ERLANG_VERSION=latest:28 ELIXIR_VERSION=1.19-otp-28 docker buildx bake

Once built, you can stream the image directly into the local sbx runtime image store:

docker image save praialabs/sandbox-templates:agy-elixir-docker | sbx template load /dev/stdin

Combining Kits and Templates

To spin up the Google Antigravity CLI sandbox with Elixir, Erlang, and pre-configured network allow-policies, run:

sbx run 'git+https://github.com/praialabs/sbx-kits.git#dir=agents/agy' \
  --kit 'git+https://github.com/praialabs/sbx-kits.git#dir=mixins/default-allow-policies' \
  --template praialabs/sandbox-templates:agy-elixir-docker