Overview
gaji is a CLI tool that allows developers to write GitHub Actions workflows in TypeScript with full type safety, then compile them to YAML. It automatically fetches action.yml definitions and generates typed wrappers, so you get autocomplete and type checking for every action input and output.
Features
- TypeScript-based workflow authoring with full type safety
- Automatic type generation from
action.ymlfiles - Composite action and reusable workflow support
- File watching for development (
--watch) - Built-in QuickJS execution with
npx tsxfallback - GitHub Enterprise support
- Single binary distribution (Rust)
Installation
From npm
From cargo
Quick Start
# Initialize a new project (creates workflows/ and generated/ directories)
# Add actions and generate types
# Run a one-time dev scan to generate types
# Build workflows to YAML
Usage
Writing Workflows
Create TypeScript files in the workflows/ directory:
import { getAction, Job, Workflow } from "../generated/index.js";
const checkout = getAction("actions/checkout@v5");
const setupNode = getAction("actions/setup-node@v4");
const build = new Job("ubuntu-latest")
.addStep(checkout({
name: "Checkout code",
with: { "fetch-depth": 1 },
}))
.addStep(setupNode({
with: { "node-version": "22" },
}))
.addStep({ name: "Install dependencies", run: "npm ci" })
.addStep({ name: "Run tests", run: "npm test" });
const workflow = new Workflow({
name: "CI",
on: {
push: { branches: ["main"] },
pull_request: { branches: ["main"] },
},
}).addJob("build", build);
workflow.build("ci");
Run gaji build and it outputs .github/workflows/ci.yml.
Recommended Development Workflow
For the best experience, follow this workflow:
-
Start watch mode:
Leave this running in a terminal. It will automatically generate types when you add new actions.
-
Edit your TypeScript workflows in
workflows/*.ts:- Add or modify steps
- Use
getAction()with full type safety - Types are automatically generated for new actions
-
Build to YAML:
-
Review the generated YAML in
.github/workflows/:- Verify commands are correct
- Check that step order is as expected
- Ensure all required fields are present
-
Commit both TypeScript and YAML:
Why Commit Both?
You should commit both the TypeScript source (workflows/*.ts) and the generated YAML (.github/workflows/*.yml):
- TypeScript: Source of truth for your workflows
- YAML: What GitHub Actions actually executes
⚠️ Important: Auto-compilation in CI
While you can create a workflow that auto-compiles TypeScript to YAML on push, this is NOT recommended. Always compile and review workflows locally before committing.
If you're willing to handle the complexity of GitHub Actions triggers (e.g., filtering paths, managing PAT tokens, avoiding infinite loops), you can set up an auto-compilation workflow. See workflows/update-workflows.ts for a working example.
Composite Actions
Define reusable composite actions and reference them in workflows:
import { CompositeAction, CallAction, Job, Workflow } from "../generated/index.js";
const action = new CompositeAction({
name: "Setup",
description: "Setup the project environment",
inputs: {
"node-version": { description: "Node.js version", required: false, default: "20" },
},
});
action.addStep({ name: "Install deps", run: "npm ci", shell: "bash" });
action.build("setup");
// Reference the composite action in a workflow
const job = new Job("ubuntu-latest")
.addStep(CallAction.from(action).toJSON());
const workflow = new Workflow({
name: "CI",
on: { push: {} },
}).addJob("build", job);
workflow.build("ci");
Reusable Workflows
Call reusable workflows using CallJob:
import { CallJob, Workflow } from "../generated/index.js";
const deploy = new CallJob("./.github/workflows/deploy.yml")
.with({ environment: "production" })
.secrets("inherit")
.needs(["build"]);
const workflow = new Workflow({
name: "Release",
on: { push: { tags: ["v*"] } },
}).addJob("deploy", deploy);
workflow.build("release");
Job Options
The Job constructor accepts an optional second argument for additional configuration:
const job = new Job("ubuntu-latest", {
needs: ["setup"],
env: { NODE_ENV: "test" },
"timeout-minutes": 30,
"continue-on-error": true,
permissions: { contents: "read" },
strategy: {
matrix: { node: ["18", "20", "22"] },
"fail-fast": false,
},
});
Builder methods are also available:
const job = new Job("ubuntu-latest")
.addStep({ name: "Test", run: "npm test" })
.needs(["setup"])
.env({ CI: "true" })
.when("github.event_name == 'push'")
.permissions({ contents: "read" })
.outputs({ result: "${{ steps.test.outputs.result }}" })
.strategy({ matrix: { os: ["ubuntu-latest", "macos-latest"] } })
.continueOnError(true)
.timeoutMinutes(30);
Commands
gaji init
Initialize a new gaji project. Detects the project state (empty, existing project, or has YAML workflows) and sets up accordingly.
gaji init [OPTIONS]
| Option | Description |
|---|---|
--force |
Overwrite existing files |
--skip-examples |
Skip example workflow creation |
--migrate |
Migrate existing YAML workflows to TypeScript |
-i, --interactive |
Interactive mode |
gaji dev
Start development mode. Scans workflow files for action references and generates types.
gaji dev [OPTIONS]
| Option | Description |
|---|---|
-d, --dir <DIR> |
Directory to scan (default: workflows) |
--watch |
Keep watching for changes after the initial scan |
gaji build
Build TypeScript workflows to YAML.
gaji build [OPTIONS]
| Option | Description |
|---|---|
-i, --input <DIR> |
Input directory containing TypeScript workflows (default: workflows) |
-o, --output <DIR> |
Output directory for YAML files (default: .github) |
--dry-run |
Preview YAML output without writing files |
Output files are placed in subdirectories based on type:
- Workflows:
.github/workflows/<id>.yml - Composite actions:
.github/actions/<id>/action.yml
gaji add <action>
Add a new action and generate types.
gaji clean
Clean generated files.
gaji clean [OPTIONS]
| Option | Description |
|---|---|
--cache |
Also clean cache |
Configuration
.gaji.toml
Project-level configuration file. Created automatically by gaji init.
[]
= "workflows" # TypeScript workflow source directory
= ".github" # Output directory for generated YAML
= "generated" # Directory for generated type definitions
[]
= 300 # Debounce delay for file watcher
= ["node_modules", ".git", "generated"]
[]
= true # Validate workflow YAML (requires 'on' and 'jobs')
= true # Format YAML output
[]
= "ghp_..." # GitHub token (prefer .gaji.local.toml for this)
= "https://github.example.com" # GitHub Enterprise URL
.gaji.local.toml
Local overrides for sensitive values. Add this to .gitignore.
[]
= "ghp_your_token_here"
= "https://github.example.com" # for GitHub Enterprise
Token resolution priority: GITHUB_TOKEN env var > .gaji.local.toml > .gaji.toml
Documentation
📚 Full Documentation (English & 한국어)
Examples
Check out the examples/ directory for complete working examples:
- ts-package - TypeScript package with gaji CI workflow using pnpm
License
MIT License