App

class marimo.App(**kwargs: Any)

A marimo notebook.

A marimo notebook is a dataflow graph, with each node computing a Python function.

async embed() → AppEmbedResult

Embed a notebook into another notebook.

The embed method lets you embed the output of a notebook into another notebook and access the values of its variables.

Example.

from my_notebook import app

# execute the notebook; app.embed() can't be called in the cell
# that imported it!
result = await app.embed()

# view the notebook's visual output
result.output

# access the notebook's defined variables
result.defs

Running await app.embed() executes the notebook and results an object encapsulating the notebook visual output and its definitions.

Embedded notebook outputs are interactive: when you interact with UI elements in an embedded notebook’s output, any cell referring to the app object other than the one that imported it is marked for execution, and its internal state is automatically updated. This lets you use notebooks as building blocks or components to create higher-level notebooks.

Multiple levels of nesting are supported: it’s possible to embed a notebook that in turn embeds another notebook, and marimo will do the right thing.

Returns.

  • An object result with two attributes: result.output (visual output of the notebook) and result.defs (a dictionary mapping variable names defined by the notebook to their values).

AppMeta

class marimo.app_meta

Get the metadata of a marimo app.

The AppMeta class provides access to runtime metadata about a marimo app, such as its display theme and execution mode.

Examples:

Get the current theme and conditionally set a plotting library’s theme:

import altair as alt

# Enable dark theme for Altair when marimo is in dark mode
alt.themes.enable("dark" if mo.app_meta().theme == "dark" else "default")

Show content only in edit mode:

# Only show this content when editing the notebook
mo.md("# Developer Notes") if mo.app_meta().mode == "edit" else None

Returns:

  • An AppMeta object containing the app’s metadata.

AppMeta.theme()

The display theme of the app.

Returns either “light” or “dark”. If the user’s configuration is set to “system”, currently returns “light”.

Examples:

Get the current theme and conditionally set a plotting library’s theme:

import altair as alt

# Enable dark theme for Altair when marimo is in dark mode
alt.themes.enable(
    "dark" if mo.app_meta().theme == "dark" else "default"
)

Returns:

  • “light” or “dark”, indicating the app’s display theme

AppMeta.mode()

The execution mode of the app.

Examples:

Show content only in edit mode:

# Only show this content when editing the notebook
mo.md("# Developer Notes") if mo.app_meta().mode == "edit" else None

Returns:

  • “edit”: The notebook is being edited in the marimo editor

  • “run”: The notebook is being run as an app

  • “script”: The notebook is being run as a script

  • None: The mode could not be determined