> For the complete documentation index, see [llms.txt](https://developer.harness.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developer.harness.io/harness-platform/3.0/harness-platform-resources/overview/overview.md). # Stage Stages are the primary execution blocks within a Harness pipeline. Each stage groups related steps and has its own runtime, settings, and configuration. A stage is the primary building block inside a pipeline. Each stage contains one or more steps that execute in sequence, along with its own runtime configuration, failure strategy, and condition settings. Pipelines are built by connecting stages on the canvas. You can run stages serially, group them to run in parallel, or chain them with conditional logic. ## What you will learn * How to add a stage to a pipeline and choose a starting stage type * What configuration sections are available on every stage * How to use stage inputs, outputs, and environment variables to pass data between stages * How execution controls (strategy, concurrency, failure handling, conditional execution, timeout) apply at the stage level * How to configure the runtime environment for a stage *** ## Add a stage To add a stage to a pipeline: 1. Open the pipeline in **Pipeline Studio**. 2. On the canvas, select the **+** (plus) button between the start and end nodes. 3. In the **Add stage** panel, choose the stage type you want to start with. 4. Configure the stage and select **Add stage**. *** ## Stage types When you add a stage, Harness prompts you to choose a starting type. The type sets up an initial configuration; it does not lock the stage to a specific purpose. For example, a **Build** stage can also run deployment steps, and a **Deploy** stage can run scripts or tests. | Type | Description | | --------------------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------- | | [**Blank canvas**](/harness-platform/3.0/harness-platform-resources/overview/overview/blank-canvas.md) | Starts with an empty stage. Add any step types manually. Use this when none of the other types fit your use case. | | [**Template**](/harness-platform/3.0/harness-platform-resources/overview/overview/blank-canvas/template.md) | Applies a pre-built stage template from the template library. The stage inherits all steps and settings defined in the template. | | [**Build**](/harness-platform/3.0/harness-platform-resources/overview/overview/blank-canvas/build.md) | Pre-configured for compiling, testing, and validating code. Expands the **Code & build** section with source connector and infrastructure settings. | | [**Deploy**](/harness-platform/3.0/harness-platform-resources/overview/overview/blank-canvas/deploy.md) | Pre-configured for deploying services to environments. Expands the **Deploy** section with service, environment, and infrastructure fields. | | [**Chained pipeline**](/harness-platform/3.0/harness-platform-resources/overview/overview/blank-canvas/chained-pipeline.md) | Runs another pipeline as a stage within this one. The child pipeline executes in full and its status determines whether this stage passes or fails. | | [**Serial group**](/harness-platform/3.0/harness-platform-resources/overview/overview/blank-canvas/serial-group.md) | Creates a container that holds multiple stages running one after another in sequence. | | [**Parallel group**](/harness-platform/3.0/harness-platform-resources/overview/overview/blank-canvas/parallel-group.md) | Creates a container that holds multiple stages running simultaneously. | {% hint style="info" %} The stage type you select at creation is a starting point, not a constraint. You can add any step type to any stage regardless of which type you chose when creating it. {% endhint %} *** ## Stage configuration After choosing a type, the **Add Stage** panel shows all available configuration sections. Each section is collapsible. | Section | Description | | ---------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------- | | **Name / Id** | The display name and unique identifier for the stage. The ID is auto-suggested from the name and is used in expressions and YAML. | | [**Deploy**](/harness-platform/3.0/harness-platform-resources/overview/overview/blank-canvas/deploy.md) | Service, environment, and infrastructure definition settings. Shown when the stage type is **Deploy** or a blank canvas. | | [**Code & build**](/harness-platform/3.0/harness-platform-resources/overview/overview/blank-canvas/build.md) | Source connector, build infrastructure, and code scanning settings. Shown when the stage type is **Build** or a blank canvas. | | [**Inputs & outputs**](/harness-platform/3.0/harness-platform-resources/overview/overview/inputs-and-outputs.md) | Stage-level input parameters, output values, and environment variables. | | [**Execution controls**](#execution-controls) | Looping strategy, concurrency, failure handling, conditional execution, and timeout. | | [**Runtime Environment**](#runtime-environment) | Where the stage runs: platform OS/arch, runtime type, and shared paths. | *** ## Inputs & outputs The **Inputs & outputs** section defines the data that flows into and out of a stage. | Field | Description | | ------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------- | | **Inputs** | Typed parameters the stage accepts at runtime. Reference them in steps using `${{ inputs. }}`. | | **Outputs** | Values the stage exports after it completes. Downstream stages and steps can reference these using `${{ stages..outputs. }}`. | | **Environment variables** | Key-value pairs injected as environment variables into all steps in the stage. | Stage inputs and outputs make it possible to build modular pipelines where data passes cleanly between stages without hardcoding values inside steps. *** ## Execution controls The **Execution controls** section configures how and when the stage runs. | Setting | Description | | ------------------------- | ------------------------------------------------------------------------------------------------------------------------------------ | | **Strategy** | Looping strategy for the stage: **matrix**, **for loop**, or **while loop**. Runs the stage multiple times with different inputs. | | **Concurrency** | Limits how many loop iterations run simultaneously when a looping strategy is applied. | | **On failure** | What Harness does if the stage fails: abort the pipeline, retry the stage, ignore the failure, or mark it as success. | | **Conditional execution** | An expression or condition that must evaluate to `true` for the stage to run. If it evaluates to `false`, the stage is skipped. | | **Timeout duration** | Maximum time the stage is allowed to run before Harness terminates it. Default is `24h`. Accepts duration format: `30m`, `2h`, `1d`. | *** ## Runtime Environment The **Runtime Environment** section controls where the stage executes. | Setting | Description | | ---------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------- | | **Platform** | The OS and architecture for the stage runner, for example, Linux/amd64 or macOS/arm64. | | **Runtime** | The infrastructure type: **Cloud** (Harness-hosted), **Docker**, a **Kubernetes** cluster, or a **local** Harness Delegate. | | **Shared paths** | Additional filesystem paths mounted and shared across all steps in the stage. Useful for passing files between steps that run in separate containers. | The runtime configuration set here applies to all steps in the stage unless a step overrides it with its own container or delegate settings. *** ## Next steps * Go to [Steps overview](/harness-platform/3.0/harness-platform-resources/overview/overview-1.md) to review step types available inside a stage. * Go to [Strategy](/harness-platform/3.0/harness-platform-resources/overview/strategy.md) to run a stage multiple times with matrix, for, or while loops.