> For the complete documentation index, see [llms.txt](https://docs.elsaworkflows.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.elsaworkflows.io/readme.md).

# Elsa Workflows 3

Elsa Workflows is a set of open-source .NET libraries designed to enhance .NET applications with workflow capabilities. Think of it as lego blocks for creating workflow engines in .NET.

{% hint style="info" %}
These docs target the Elsa 3.8.0 stable package family. See [Upgrade to Elsa 3.8.0](/getting-started/upgrading-to-3.8.md) for the release sources, security defaults, and module registration checklist.
{% endhint %}

Workflows in Elsa can be defined in different ways:

* Programmatically by writing .NET code.
* Visually using the built-in designer, non-developers or those who prefer a visual approach can create and modify workflows with ease.
* Declaratively using JSON.

## Defining Workflows

Define workflows programmatically using .NET code:

```csharp
// Define workflows directly from code.
var workflow = new Sequence
{
    Activities =
    {
        new WriteLine("Hello World!"),
        new Delay(TimeSpan.FromSeconds(1)),
        new WriteLine("It is nice to meet you!")
    }
};
```

And/or, define workflows visually using [Elsa Studio](/application-types/elsa-studio.md):

<div data-full-width="false"><figure><img src="/files/fZt5sjxNU1tF2pLnldTm" alt=""><figcaption><p><kbd>Design workflows visually</kbd></p></figcaption></figure></div>

And/or, define workflows declaratively using JSON:

```json
{
  "id": "1",
  "definitionId": "1",
  "name": "Hello World",
  "version": 1,
  "root": {
    "id": "Flowchart1",
    "type": "Elsa.Flowchart",
    "activities": [
      {
        "id": "WriteLine1",
        "type": "Elsa.WriteLine",
        "text": {
          "typeName": "String",
          "expression": {
            "type": "Literal",
            "value": "Hello World!"
          }
        }
      }
    ]
  }
}
```

## Use Cases

1. **Integrate Workflow Execution in .NET Applications**: Add workflow execution capabilities to existing applications.
2. **Standalone Workflow Server**: Deploy Elsa as an independent workflow server to manage various business processes across your organisation.
3. **Prebuilt Docker Containers**: Instead of building a custom workflow server, there is the option of hosting a prebuilt Docker image that acts as a standalone workflow server that exposes REST APIs to interact with the engine.

## Key Features

1. **Long & Short Running Workflows**: Workflows can both be short-lived completing in milliseconds, as well as long-lived, potentially spanning hours, days, weeks, months and even years.
2. **Activity Library**: Elsa offers a rich set of out-of-the-box activities, providing essential building blocks to construct flexible and effective workflows tailored to your business needs.
3. **Triggers**: Workflows can be initiated automatically based on specific events or conditions, enabling seamless automation and integration with existing processes.
4. **Dynamic Expressions**: Elsa allows the use of C#, JavaScript, or Liquid expressions for dynamic value evaluation during runtime, enhancing workflow logic. You can customize it as Elsa is highly modular and extensible.
5. **Extensibility**: Elsa is built to be extensible, making it easy to add custom activities and connect with other systems.
6. **Reusable Web-Based Designer**: With the web-based drag & drop designer hosted in Elsa Studio, users can visually create workflows, leveraging a modular and extensible framework.
7. **Scalable Performance**: Elsa is designed for high performance, working across multiple nodes in a cluster for horizontal scaling.

## Known Limitations

Elsa is continually evolving, and while it offers powerful capabilities, there are some known limitations and ongoing work:

* Documentation is still a work in progress.
* The editor's **Run Workflow** action sends an empty execution request. Use a trigger or the API when the workflow requires inputs or must start through a trigger; the editor does not collect those values in that action.
* Flowchart, Sequence, and StateMachine designers are available in the Elsa Studio 3.8.0 release. Sequence and StateMachine use their own editing surfaces and may expose different editing constraints than Flowchart.
* Studio validates required editor fields and reports server-side validation errors while saving or publishing. It does not provide a general-purpose input form for the Run Workflow action.