Greenlight

A GitHub Actions workflow visualizer built with Phoenix LiveView. View your CI/CD pipelines as interactive DAGs, drill down from workflow-level to individual jobs, and track runs across organizations and repositories.

Features

• Interactive DAG visualization of GitHub Actions workflows using Svelte Flow
• Real-time polling of workflow run status
• Expandable job nodes — click a workflow to see its jobs and dependency graph
• Dashboard for followed organizations and bookmarked repositories
• Repository browser with workflow run history
• Pipeline view per commit with dependency resolution from workflow YAML

Architecture

Greenlight uses Phoenix LiveView for real-time UI and Ash Framework as a declarative data layer for GitHub API resources.

• Ash Domain (Greenlight.GitHub) provides a single code interface for all GitHub data access
• 10 Ash Resources model GitHub objects (WorkflowRun, Job, Step, Repository, Pull, Branch, Release, User, UserPR, UserCommit)
• ManualRead Actions bridge the Ash domain to the GitHub REST API via a lightweight HTTP client
• GenServers (Poller, UserInsightsServer) handle polling and caching, calling through the Ash domain
• LiveViews subscribe to PubSub updates and render real-time DAG visualizations with Svelte Flow

Prerequisites

• Elixir ~> 1.15
• Node.js (for asset compilation)
• A GitHub Personal Access Token with repo and actions read access
• (Optional) Nix with flakes enabled — the repo includes a flake.nix for a reproducible dev environment

Setup

Clone the repo and install dependencies:

git clone https://github.com/jordangarrison/greenlight.git
cd greenlight
mix setup

If you use Nix and direnv, the dev environment loads automatically. Otherwise, make sure Elixir and Node.js are installed.

Configuration

Create a .env file in the project root:

export GITHUB_TOKEN="your_github_token"
export GREENLIGHT_BOOKMARKED_REPOS="owner/repo1,owner/repo2"
export GREENLIGHT_FOLLOWED_ORGS="my-org,another-org"

If you use direnv, these will be loaded automatically via .envrc. Otherwise, source the file before starting the server:

source .env

Variable	Required	Description
GITHUB_TOKEN	Yes	GitHub PAT with repo and actions read access
GREENLIGHT_BOOKMARKED_REPOS	No	Comma-separated list of owner/repo to pin on the dashboard
GREENLIGHT_FOLLOWED_ORGS	No	Comma-separated list of GitHub orgs to follow

Running

mix phx.server

Then visit localhost:4000.

Development

# Run the formatter, compiler warnings check, and tests
mix precommit

# Run tests only
mix test

Container

Build a Docker image using Nix (requires Nix with flakes enabled):

nix build .#dockerImage
docker load < result

Run the container with the required environment variables:

docker run -p 4000:4000 \
  -e SECRET_KEY_BASE="$(mix phx.gen.secret)" \
  -e GITHUB_TOKEN="your_github_token" \
  -e PHX_HOST="localhost" \
  ghcr.io/jordangarrison/greenlight:latest

Then visit localhost:4000.

Variable	Required	Description
SECRET_KEY_BASE	Yes	Phoenix session signing key (generate with mix phx.gen.secret)
GITHUB_TOKEN	Yes	GitHub PAT with repo and actions read access
PHX_HOST	Yes	Public hostname for URL generation
PORT	No	HTTP listen port (default: 4000)
GREENLIGHT_LISTEN_ADDRESS	No	Bind address (default: 0.0.0.0 in container)
GREENLIGHT_BOOKMARKED_REPOS	No	Comma-separated list of owner/repo to pin
GREENLIGHT_FOLLOWED_ORGS	No	Comma-separated list of GitHub orgs to follow

License

MIT — see LICENSE.