streamweave-attractor

An implementation of StrongDM's Attractor—a non-interactive coding agent for use in a software factory—built on StreamWeave.

Attractor is specified by NLSpecs (Natural Language Specs): human-readable specs intended for coding agents to implement and validate behavior. This repository implements that spec using StreamWeave, a composable, async, stream-first Rust framework for building data processing graphs.

Overview

• Attractor (strongdm/attractor): Defines the coding agent loop, unified LLM interface, and overall behavior for a software factory agent.
• StreamWeave (Industrial/streamweave): Provides the runtime—graph-based, async stream processing in Rust—used to run the agent loop, tool calls, and I/O.

Together, this project gives you an Attractor-compliant agent implemented in Rust with StreamWeave’s streaming and graph abstractions.

Specs (upstream)

The authoritative Attractor specs live in the upstream repo:

• Attractor Specification
• Coding Agent Loop Specification
• Unified LLM Client Specification

Building and running

Running via CLI

run_dot runs an Attractor pipeline from a .dot file (parse → validate → run):

devenv shell -- cargo run --bin run_dot -- examples/workflows/pre-push.dot

Options (see run_dot --help for full usage): --agent-cmd, --stage-dir (default: .attractor), --run-dir, --resume. Run state is persisted only via the execution log. Use --run-dir DIR with --execution-log to write DIR/execution.log.json, and --resume DIR to resume from DIR/execution.log.json with the same .dot file.

Environment variables:

• ATTRACTOR_AGENT_CMD — Command for agent/codergen nodes (e.g. cursor-agent). When set, agent steps run this with the prompt as stdin; outcome is read from ATTRACTOR_STAGE_DIR.
• ATTRACTOR_STAGE_DIR — Directory for agent outcome.json and staging (default: .attractor).

Example:

devenv shell -- cargo run --bin run_dot -- examples/workflows/pre-push.dot

The main entry point is the simple_pipeline example, which runs a minimal Attractor graph (Run tests → Report). You can run it in several ways:

Examples:

# Run from Nix (no Rust install needed)
nix run github:Industrial/streamweave-attractor

# Run from local checkout with devenv
devenv shell -- cargo run --example simple_pipeline

# Build only
devenv shell -- cargo build --examples

Nix flake (Cargo.lock and path dependency)

• Cargo.lock is committed so that when the repo is used as a flake input (e.g. github:Industrial/streamweave-attractor), Nix can use it for reproducible builds. Do not add Cargo.lock to .gitignore.
• The flake depends on streamweave via input streamweave (default: path:../streamweave). When the flake is consumed from GitHub (e.g. by another project’s devenv), that path does not exist. Override the input in the consuming flake, for example:

  streamweave-attractor.url = "github:Industrial/streamweave-attractor";
  # Override so the build can find streamweave:
  streamweave-attractor.inputs.streamweave.url = "github:Industrial/streamweave";
  # or path: ./streamweave if you have it in your tree
  

• cargo2nix is integrated optionally. The default package uses buildRustPackage. To use cargo2nix (granular Rust builds), generate Cargo.nix once and commit it:

  nix run .#generate
  git add Cargo.nix
  

  Then nix build .#cargo2nix builds the workspace crate via cargo2nix. The default nix build / nix run still use buildRustPackage and do not require Cargo.nix.

Development

devenv shell -- cargo build
devenv shell -- cargo run --example simple_pipeline

Pre-push quality gates

Run all quality checks before pushing:

devenv shell -- bin/pre-push

This runs: format, fix, check, lint, build, test, audit, check-docs. (Examples like simple_pipeline require an LLM—run bin/test-examples manually when needed.) See examples/workflows/pre-push.dot for the bd-centric fix-and-retry workflow.

See CONTRIBUTING.md and AGENTS.md for development workflow and agent instructions.

Installing as a CLI in another project (devenv)

You can install streamweave-attractor as a CLI in another project’s devenv environment so the streamweave-attractor binary is available in the shell.

1. Add the flake input

In the other project, add streamweave-attractor as an input.

If that project uses a devenv.yaml (standalone devenv), add:

# devenv.yaml
inputs:
  streamweave-attractor:
    url: github:Industrial/streamweave-attractor
  # Optional: use a local checkout instead of GitHub
  # streamweave-attractor:
  #   path: ../streamweave-attractor

If that project uses a Nix flake (e.g. flake.nix with devenv), add the same input to the flake’s inputs and ensure it is passed through to the devenv module (e.g. via inputs in perSystem or your devenv integration).

2. Add the package in devenv.nix

In the other project’s devenv.nix, add the package so it is on PATH:

{ inputs, pkgs, ... }: {
  packages = with pkgs; [
    # your other packages ...
    inputs.streamweave-attractor.packages.${pkgs.system}.default
  ];
}

After devenv shell (or entering the environment), you can run:

streamweave-attractor

The flake’s default package builds the simple_pipeline example and installs it as the streamweave-attractor binary. For run_dot (DOT-based pipelines), use this repo’s devenv and run:

cargo run --bin run_dot -- examples/workflows/pre-push.dot

License

This project is licensed under the Creative Commons Attribution-ShareAlike 4.0 International License. See LICENSE for details.