> ## Documentation Index
> Fetch the complete documentation index at: https://athanor.alexisbouchez.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Supported Features

> GitHub Actions features that Athanor supports

## Workflow Syntax

<CardGroup cols={2}>
  <Card title="run: steps" icon="terminal">
    Shell scripts executed via bash (or configured shell)
  </Card>

  <Card title="uses: actions" icon="puzzle-piece">
    GitHub actions, local actions, composite actions, Node.js actions
  </Card>

  <Card title="Job dependencies" icon="diagram-project">
    `needs:` with DAG resolution and concurrent execution
  </Card>

  <Card title="Matrix strategy" icon="table-cells">
    Cartesian product expansion with include/exclude
  </Card>

  <Card title="Expression engine" icon="calculator">
    Full expression evaluation with contexts, operators, and functions
  </Card>

  <Card title="Environment variables" icon="sliders">
    `env:` at workflow, job, and step levels + `$GITHUB_ENV`
  </Card>

  <Card title="Step outputs" icon="arrow-right-arrow-left">
    `$GITHUB_OUTPUT` with multiline delimiter support
  </Card>

  <Card title="Job outputs" icon="share-nodes">
    `jobs.*.outputs` evaluated from step outputs
  </Card>

  <Card title="Conditions" icon="code-branch">
    Full expression evaluation in `if:` with status functions
  </Card>

  <Card title="Timeouts" icon="clock">
    `timeout-minutes` at job and step level
  </Card>

  <Card title="continue-on-error" icon="forward">
    Step failures don't fail the job
  </Card>

  <Card title="GitHub context" icon="github">
    `github.sha`, `github.ref`, `github.repository`, `github.actor`, etc.
  </Card>

  <Card title="Secrets" icon="key">
    `secrets.*` context populated from server environment variables
  </Card>

  <Card title="Concurrency" icon="lock">
    `concurrency:` groups with `cancel-in-progress` support
  </Card>

  <Card title="Permissions" icon="shield">
    `permissions:` field parsed at workflow and job level
  </Card>

  <Card title="Container" icon="cube">
    `container:` runs job steps inside a Docker container
  </Card>

  <Card title="Services" icon="cubes">
    `services:` starts sidecar containers alongside the job
  </Card>

  <Card title="Artifacts" icon="box-archive">
    `actions/upload-artifact` and `actions/download-artifact` built-in shims
  </Card>

  <Card title="Reusable workflows" icon="recycle">
    `workflow_call` with inputs and secret inheritance
  </Card>

  <Card title="Branch filters" icon="filter">
    `on: push: branches:` and `branches-ignore:` filters
  </Card>

  <Card title="$GITHUB_PATH" icon="route">
    PATH modifications persist across steps (including in VMs)
  </Card>
</CardGroup>

## Expression Functions

| Function                     | Description                                      |
| ---------------------------- | ------------------------------------------------ |
| `contains(search, item)`     | Case-insensitive string/array search             |
| `startsWith(string, prefix)` | Case-insensitive prefix check                    |
| `endsWith(string, suffix)`   | Case-insensitive suffix check                    |
| `format(string, args...)`    | String formatting with `{0}`, `{1}` placeholders |
| `join(array, separator)`     | Join array elements                              |
| `toJSON(value)`              | Convert to JSON string                           |
| `fromJSON(string)`           | Parse JSON string                                |
| `success()`                  | True if job has not failed                       |
| `failure()`                  | True if any previous step failed                 |
| `always()`                   | Always true                                      |
| `cancelled()`                | True if workflow was cancelled                   |

## Expression Contexts

| Context     | Description                                |
| ----------- | ------------------------------------------ |
| `github.*`  | Repository, commit, ref, actor, event info |
| `env.*`     | Environment variables                      |
| `steps.*`   | Step outputs and outcomes                  |
| `needs.*`   | Dependent job outputs and results          |
| `matrix.*`  | Current matrix combination values          |
| `runner.*`  | Runner OS, architecture, temp directory    |
| `job.*`     | Current job status                         |
| `inputs.*`  | Workflow/action inputs                     |
| `secrets.*` | Secret values from server configuration    |

## Action Support

| Type              | Example                                                      | Status                                         |
| ----------------- | ------------------------------------------------------------ | ---------------------------------------------- |
| GitHub actions    | `actions/checkout@v4`                                        | Supported (built-in shim)                      |
| Setup actions     | `actions/setup-node@v4`, `actions/setup-go@v5`               | Supported (built-in shim, tools pre-installed) |
| Artifact actions  | `actions/upload-artifact@v4`, `actions/download-artifact@v4` | Supported (built-in shim, local storage)       |
| Local actions     | `./my-action`                                                | Supported                                      |
| Composite actions | `runs.using: composite`                                      | Supported                                      |
| Node.js actions   | `runs.using: node20`                                         | Supported (requires Node on PATH)              |
| Docker actions    | `docker://image`                                             | Not supported                                  |

## CI Server Features

| Feature            | Description                                                           |
| ------------------ | --------------------------------------------------------------------- |
| GitHub webhooks    | Receives `push` and `pull_request` events with branch filtering       |
| Commit statuses    | Reports pass/fail via the Statuses API                                |
| Checks API         | Full log output per workflow (requires GitHub App)                    |
| MicroVM isolation  | Each job runs in an ephemeral CloudHypervisor VM                      |
| Parallel VMs       | Independent jobs run concurrently, configurable via `VM_MAX_PARALLEL` |
| virtiofs sharing   | Workspace shared between host and VM                                  |
| Web dashboard      | Real-time build status with per-step log viewing                      |
| SSE updates        | Live streaming of build progress to the browser                       |
| Concurrency groups | Prevents concurrent runs of the same workflow/branch                  |
| Secrets management | `SECRET_*` env vars exposed as `secrets.*` context                    |
| Artifacts          | Local artifact storage shared between jobs                            |
| Container jobs     | Run steps inside Docker containers                                    |
| Service containers | Sidecar containers for databases, caches, etc.                        |
| Reusable workflows | Call other workflow files with inputs and secrets                     |

## Secrets

Secrets are loaded from environment variables on the server. Any env var prefixed with `SECRET_` is exposed in the `secrets.*` context with the prefix stripped.

For example:

```bash theme={null}
# In /etc/athanor/env
SECRET_SSH_PRIVATE_KEY=...
SECRET_STRIPE_KEY=sk_test_...
```

These become available in workflows as `${{ secrets.SSH_PRIVATE_KEY }}` and `${{ secrets.STRIPE_KEY }}`.

## Container Support

Jobs can specify a Docker container image. All `run:` steps execute inside the container with the workspace mounted:

```yaml theme={null}
jobs:
  test:
    container: node:20-alpine
    steps:
      - uses: actions/checkout@v4
      - run: npm test
```

Service containers run alongside the job and are accessible via `localhost`:

```yaml theme={null}
jobs:
  test:
    services:
      postgres:
        image: postgres:16
        env:
          POSTGRES_PASSWORD: test
        ports:
          - 5432:5432
    steps:
      - run: pg_isready -h localhost
```

<Note>
  Container and service support requires Docker to be installed in the VM rootfs.
</Note>

## Concurrency

Prevent concurrent runs of the same workflow:

```yaml theme={null}
concurrency:
  group: deploy
  cancel-in-progress: true
```

When a new run starts for the same group, the previous run is cancelled.