# atmos store set

Write a value to a configured store backend. This command creates a new value or updates an existing one. You can supply the value inline. You can also pipe the value in with `--stdin`. Or, if you run the command in a terminal with no `VALUE` argument, Atmos prompts you for the value and masks your input. You do not need to declare a key first. You can write any `KEY` to any configured store.

## Usage

```shell
atmos store set STORE KEY [VALUE] [flags]
```

## Examples

```shell
# Set a value inline, scoped to a stack and component
atmos store set app-metadata image_tag sha256:abc123 --stack=prod --component=ecs-service

# Set a value interactively with a masked prompt
atmos store set app-metadata image_tag --stack=prod --component=ecs-service

# Read a multi-line value from standard input
cat manifest.json | atmos store set app-metadata deploy_manifest --stdin --stack=prod --component=ecs-service

# Store-global value (no --stack/--component)
atmos store set app-metadata shared_config '{"region":"us-east-1"}'

# Write to a store using a specific identity
atmos store set app-metadata image_tag sha256:abc123 --stack=prod --component=ecs-service --identity=aws/prod-metadata
```

## Arguments

- **`STORE`**

  The name of the configured store backend. This name is a key under `stores:` in `atmos.yaml`.
- **`KEY`**

  The key to write.
- **`VALUE`**

  The value to write. This argument is optional. If you omit it, Atmos reads the value from `--stdin` or from an interactive masked prompt.

## Flags

- **`--stack` (alias `-s`)**

  The Atmos stack to scope the key to. This flag is optional. Omit it to store a global key.

  **Environment variable:** `ATMOS_STACK`
- **`--component` (alias `-c`)**

  The Atmos component to scope the key to. This flag is optional. Omit it to store a global key.

  **Environment variable:** `ATMOS_COMPONENT`
- **`--identity` (alias `-i`)**

  The identity Atmos uses to access the store backend.

  **Environment variable:** `ATMOS_IDENTITY`
- **`--stdin`**

  Read the value from standard input. Use this flag to pipe multi-line values, such as JSON manifests.

## See Also

- [atmos store](/cli/commands/store/usage) — Overview of the store command group
- [`!store` YAML function](/functions/yaml/store) — Read a value back scoped to a stack and component